CHAPTER 8 · Final Report Rehabilitation of Gates and Penstock -Preparatory Survey on Hydropower Plants Rehabilitation Project in Myanmar. ... The actual thickness of skin plate of

Chapter 8 Final Report Rehabilitation of Gates and Penstock

- Preparatory Survey on Hydropower Plants Rehabilitation Project in Myanmar

CHAPTER 8

REHABILITATION OF GATES AND PENSTOCK


8 - 1 Preparatory Survey on Hydropower Plants Rehabilitation Project in Myanmar

Chapter 8 Rehabilitation of Gates and Penstock

Method, Results of Site Reconnaissance and Issues

JICA (Japan International Cooperation Agency) Survey Team visually inspected the gate and penstock facilities in Baluchaung No.1 HPP (Hydropower Plant) and Sedawgyi HPP. In addition, JICA Survey Team measured thickness of skin plate of some gate leaves and penstocks. The result is described below.

8.1.1 Baluchaung No.1 Hydropower Plant

The gate and penstock facilities in Baluchaung No.1 HPP has been well maintained basically.

Generally, the condition of gates, stoplogs and other facilities were deteriorated because of aging. Especially, the reliability of control panels were decreased.

Though the hoist has been re-painted (touch up) every 3 years, the condition of paint was not so good because the old paint and corrosion were not removed at the time of re-paint.

There were no vibration and noise and the ammeter and voltmeter indicated no fluctuation while the gates were operating.

Some indication lamps and fluorescent bulbs have burn out, but the lamps and bulbs are available in Myanmar.

(1) Intake Dam

The intake dam has following facilities; - Spillway gate and stoplog - Intake gate and stoplog - Raking system - Remote control and emergency generator

1) Spillway Gate and Stoplog

The spillway gates have been operated only when a flood comes due to the rainfall. The number of times for operation is different from each years because it depends on the actual rainfall. The stoplogs are kept at storage position and used only for maintenance of spillway gates.

The actual thickness of skin plate of stoplog gate leaf were measured and it was decreased by 0.15mm at the minimum point, compared to the designed thickness.

As for spillway gates, the following issue was found; - There were gaps between indication of position indicator and actual gate position.

The conditions of spillway gates and stoplogs are as follows;

Chapter 8 Rehabilitation of Gates and Penstock Final Report

Preparatory Survey on Hydropower Plants 8 - 2 Rehabilitation Project in Myanmar

Gate leaf and guide frame of spillway gate seem to be in

sound condition.

Gate leaf and guide frame of spillway stop log seem to be

in sound condition.

The paint of hoists is deteriorated because of aging.

There were gaps between indication of position indicator

and actual gate position.

Local control panel was deteriorated because of aging.

The inside of local control panel is in bad condition

because of humidity and small animals.

The conditions of hoist and control of spillway stoplog

were deteriorated because of aging.

Photo 8.1-1 Conditions of Spillway Gates and Stoplogs



Table 8.1-1 Number of Times for Intake Spillway Gate Operation

Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec

2011 4 3 3 - 34 11 16 242 102 33 61 209

2013 - - - - 5 4 3 68 63 119 150 91

2015 - 31 - 11 - 1 26 59 - 2 2 - (Times)

2) Intake Gate and Stoplog

The intake gates has been operated several times every day for the purpose of regulating the amount of water flow for the generation.

The stoplogs have not been used from the construction stage. A truck crane should be hired when the stoplogs are being lowered and opened.

As for intake gates, the following issues were found; - No.3 ammeter is not working - No.1 ~ No.3 the limit switch of “Fully Lowered” is not working. The hoist stopped based

on the error signal of over torque at the fully lowered position. - There were gaps between indication of position indicator and actual gate position.

The conditions of intake gates and stoplogs are as follows;

The condition of gate leaves was relatively good.

Some gates had water leakage.

The condition of hoist was relatively good. Stoplogs are

stored under the grating cover.

There were gaps between indication of position indicator





Photo 8.1-2 Conditions of Intake Gates and Stoplogs

3) Raking System

The raking system has been operated every 2 days. The river has been carrying a huge amount of garbages because the residents in Loikaw city have thrown gavages into the river.

As for raking system, the following issue was found; - The control panel was deteriorated because of aging.

The conditions of the raking system are as follows;

The raking system was deteriorated because of aging.

The rake needs to be balanced between its right and left

position to be lowered properly.

There were slight noise and vibration during the belt

conveyer was operating.

The lubrication tube was broken.



The emergency button was deteriorated because of

aging.

The limit switches were not working.

Photo 8.1-3 Conditions of Raking System

4) Remote Control and Emergency Generator

There were a remote control panel and emergency generator in the house located at the right bank of intake dam. Both of the control panel and emergency generator were deteriorated because of aging.

The conditions of the remote control and emergency generator are as follows;

There was a remote control panel and emergency

generator in the house.

The remote control panels were deteriorated because of

aging.

The water level indications were not correct.

The emergency generator needed more than 15 minutes

to be started due to deterioration of the battery.

Photo 8.1-4 Conditions of Remote Control and Emergency Generator



(2) Head Pond

The head pond has following facilities; - Inlet gate - Sand flash gate - Raking system

1) Inlet Gate

The inlet gate has been operated only for maintenance of penstocks. In this survey, inlet gate was operated to fully close position, and it was the 4th time to de-water the penstock from the construction stage.

The actual thickness of skin plate of inlet gate leaf were measured and, compared to the designed thickness, there was no decreasing with the thickness.

As for inlet gate, the following issues were found; - There were gaps between indication of position indicator and actual gate position.

The conditions of the inlet gate are as follows.

The condition of gate leaf was relatively good.

The hoist was deteriorated because of aging. The

reliability of local control panel was decreased because of the deterioration.

The battery panel was out of service.

There was a gap between indication of position indicator


Photo 8.1-5 Conditions of Inlet Gate



2) Sand Flash Gate

The sand flash gate has been out of service for 3 years because of failure of main gate. The main gate has not been moved by motor or man power since 2013. Before the failure, the sand flash gate was operated every 3 months for the purpose of flashing the sediments.

According to the mechanical staff, the guard valve was in sound condition but they can’t operate the guard valve because the main valve was slightly opened. The guard valve is designed to be operated under balanced condition.

The spindle of main valve has a buckling as it turned out in September 2016.

The condition of the sand flash gate is as follows.

The main valve can’t have been operated.

The guard valve. All gates of the sand flash facilities were

embedded.

The spindle is bended.

The control panel is deteriorated because of aging.

Photo 8.1-6 Conditions of Sand Flash Gate

3) Raking System

The raking system has been operated twice a month. The gavages were fewer than the intake dam. The raking system was out of order due to small problem at the time of site investigation but it is possible to fix by mechanical staff. The gavages had been removed manually for a while. .

As for sand flash gate, the following issues were found; - Main valve is out of order because of the failure of hoist.



- The control panel was deteriorated because of aging.

The conditions of the raking system are as follows;

The raking system was out of service.

There was a small problem with chain and gear.

The emergency stop button was broken.

The limit switches were not working properly.

The gavages were removed manually because of failure of

the raking system. Photo 8.1-7 Conditions of Raking System

(3) Low Pressure Pipe Line, Surge Tank and Penstock

1) By-pass Valve

The by-pass valves were in sound condition.

2) Low Pressure Pipe Line

The low pressure pipe line had leakage from some expansion joints. The amount of water



leakage is showed in Table 8.1-2. All expansion joints were checked and re-tightened if necessary in 2014.

On the steel pipe and support metal, paint had damaged due to aging, heat and scratches. In addition, there were some corroded parts on the outer surface. On the other hand, the internal surface is relatively clean.

Though the actual thickness of steel pipe were measured and compared with the designed thickness, there was no decreasing with the thickness.

There were no leakage at the manhole even after the internal visual inspection.

The conditions of the low pressure pipe line are as follows;

There were water leakages from some expansion joints.

The trace of water leakage. It can cause damages to the

paint.

The damaged paint.

Corroded part of outer surface.

Photo 8.1-8 Conditions of By-pass Valves



Corroded part on the support.

Inside of the L.P.P.L. was relatively clear.

Photo 8.1-9 Conditions of Low Pressure Pipe Line

Table 8.1-2 Amount of Water Leakage at each Expansion Joint

No. Amount No. Amount No.1 Approx. 1.5L/min No.8 Approx. 2.5L/min No.2 < 1.0L/min No.9 < 1.0L/min No.3 - No.10 Approx. 1.4L/min No.4 - No.11 Approx. 1.5L/min No.5 Approx. 14L/min No.12 Too much for measuring No.6 Too much for measuring No.13 - No.7 < 1.0L/min No.14 -

3) Surge Tank

The surge tank was in sound condition. The expansion joint had water leakage once, but after re-tighten, there have been no leakage.

The surge tank was in sound condition.

There was no leakage at the expansion joint.

Photo 8.1-10 Conditions of Surge Tank

4) Penstock

The penstock had leakage from No.1 expansion joint. The amount of water leakage was approximately 9.0 litter per minute. Both of No.1 and No.2 expansion joints were checked and re-tightened in 2014.



There was damaged paint on some support metals. In addition, there were some corroded parts. On the other hand, the steel pipe seemed to be in sound condition and the internal surface was relatively clean.

The actual thickness of steel pipe were measured and, compared to the designed thickness, there was no decreasing with the thickness.

There was no leakage at the manhole even after the internal visual inspection.

The conditions of the penstock are as follows;

There was water leakage from No.1 expansion joint.

Damaged paint and corrosion on a support metal.

Inside of the penstock was relatively clear.

Photo 8.1-11 Conditions of Penstock

(4) Emergency Discharge Valve

1) Main Valve

The main valve had a small amount of water leakage from the metal seal. In addition, according to the mechanical staff, the main valve also had oil leakage from power cylinder before.

The position indicator is not accurate because of broken messenger wire. Mechanical staff tied the wire after it had been broken.

The control panel was deteriorated because of aging. The conditions of the main valve are as follows;



There was slight water leakage from metal seal.

The trace of oil leakage from power cylinder.

The position indicator is not accurate

The reliability of control panel was decreased because of

the deterioration.

Photo 8.1-12 Conditions of Main Valve

2) Guard Valve

Generally the guard valve was deteriorated because of aging. The control panel and oil pressure unit are common with the main valve.

The guard valve was deteriorated but no failure

had been recorded.

The oil pressure unit seemed to be in sound condition.

Photo 8.1-13 Conditions of Guard Valve



3) Others

The motor of shutter of hoist room was broken and removed. Therefore, the shutter could not be opened.

The shutter could not be opened.

The motor had been removed.

Photo 8.1-14 Conditions of Shutter of Hoist Room

(5) Tailrace Gate

Generally, the tailrace gate was working properly though the hoist was deteriorated because of aging.

The tailrace gate was working properly.

The hoist was deteriorated.

Photo 8.1-15 Conditions of Tailrace Gate

(6) Baluchaung No.2 HPP Headrace Channel Gate

1) Upstream Gate

The upstream gate has been used when the headrace channel needs maintenance.

Generally the upstream gate seemed to be in sound condition. The actual thickness of skin plate of upstream gate was measured and it was decreased by 0.35mm at the minimum point, compared to the designed thickness.

The factory manager requested us to provide one more gate leaf at Baluchaung No.2 HPP upstream gate for the purpose that Baluchaung No.1 HPP can generating with small power discharge during shut down of Baluchaung No.2 HPP.





Photo 8.1-16 Conditions of Upstream Gate

2) Downstream Gate

The downstream gate has not been used from the construction stage. Generally the upstream gate seemed to be in sound condition.



Photo 8.1-17 Conditions of Downstream Gate

(7) Mobye Dam

1) Spillway Gate

There are the spillway gates in Mobye dam. Though the spillway gates have been under the control of DHPI (Department of Hydropower Implementation), the spillway gates are positioned upstream of Baluchaung River system, therefore the failure of the gates will influence generation directly.

Generally, the spillway gates were deteriorated heavily because of aging. Especially, the local and remote control were out of service. Therefore the operator had to switch the relays in the control panel directly. In addition, the hoist was also deteriorated heavily. According to the headquarters of MOEE (Ministry of Electricity and Energy), DHPI has a maintenance plan for the spillway gates.

The conditions of the spillway gates are as follows;



Paint on the spillway gates were deteriorated. The gate

had water leakage.

The hoist made noise and vibration during gate operation.

The hoist seemed not to be maintained properly.

The control panel was deteriorated due to aging.

No.3 voltmeter was broken.

There were gaps between the indication of position

indicator and actual gate position.

The remote control panes was out of service.

Photo 8.1-18 Conditions of Spillway Gates



2) Navigation Lock

There is a set of navigation lock in Mobye dam and the lock has not been used for 16 years. Before that, there were ship transportation for around 15 ships per day in average.

Generally, the navigation lock was deteriorated heavily because of aging. On the other hand, the barrier and bridge had never been used from the construction stage so the control functions for these facilities can be omitted at the replacement. In addition, the damages of the windows and walls of the control house cause the weathering damage to the control and oil pressure unit.

The conditions of the navigation lock are as follows;

Paint on the navigation lock were deteriorated. The gate

had water leakage at water tight seal and butterfly valves.

There were oil leakage at power cylinder.

The oil pressure unit was deteriorated.

The control panel was deteriorated due to aging.

The windows were broken.

Photo 8.1-19 Conditions of Navigation Lock



8.1.2 Sedawgyi Hydropower Plant

(1) Powerhouse Facilities

Sedawgyi powerhouse has following facilities: - Draft tube gate - Penstocks

1) Draft Tube Gate

Generally, the draft tube gate seemed to be in sound condition.

The draft tube gate seemed to be in sound condition.

The gate leaf was in sound condition.

The hoist was deteriorated because of aging but working

properly. Photo 8.1-20 Conditions of Draft Tube Gate

2) Penstock

The penstock was embedded type, therefore only failure record was checked with interview. As a result, there was no failure record concerning the penstock.

(2) Dam Facilities

Sedawgyi dam has following facilities: - Spillway gate and stoplog - Irrigation gate and guard gate - Penstock gate and maintenance gate

These facilities are under the control of Irrigation Department (hereinafter ID) of MOALI (Ministry of Agriculture, Livestock and Irrigation). All of these gate facilities and stoplog for



penstock gate had water leakage.


The spillway gates were deteriorated heavily because of aging. In addition, No.1 and No.7 gates have not been able to fully open. According to the ID, ID will apply the necessary repair to the failures with spillway gates.

The stoplogs have not been used from the construction stage. A truck crane should be hired when the stoplogs are being lowered and opened.

The conditions of spillway gates and stoplogs are as follows;

Paint on the spillway gates were deteriorated. The gate

had water leakage.

According to mechanical staff, the hoist made noise and

vibration during gate operation. There were oil leakage from gear boxes.

The control panel was deteriorated heavily because of

aging.

The stoplogs had no failure.

Photo 8.1-21 Conditions of Spillway Gates and Stoplogs

2) Irrigation Gate and Guard Gate

The irrigation gate has been used when the generation is stopped or the water level is lower than low water level.

The irrigation gate was deteriorated heavily because of aging. The control panel was out of service.

The conditions of the irrigation gate and guard gate are as follows;



Usually, the irrigation gate has been closed and the guard

gate has been hooked in the rest position.

There were oil leakage from gear boxes.

The control panel was out of service.

Photo 8.1-22 Conditions of Irrigation Gate and Guard Gate

3) Penstock Gate and Maintenance Gate

The penstock gates have not been used because they have had water leakage from the construction stage. Mainly, the maintenance gates (stoplog) has been used for the purpose of maintenance of penstock, turbine and generating facilities. However, the penstock gate should be used for the purpose of maintenance of these facilities and in the case of emergency shutdown. These functions have been out of working order.

At the time of site investigation, there was water leakage over 9.0 m3/min from maintenance gates. According to the staff, No.1 gate had water leakage more than 7.0m3/min, and No.2 gate had water leakage less than 2.0m3/min.

According to the maintenance manual, the penstock gate leaf shall be uplifted with gantry crane. But, when ID staff tried to uplift the gate leaf with the gantry crane, it stopped due to over load. The gantry crane can operate only the stoplogs.

The hoist has a remote control panel at the power plant, but it is out of order. The reliability of local control panel was decreased because of deterioration.

According to ID, ID has a plan to fix the water leakage from the concrete crack above the maintenance gate.

The conditions of the penstock gates and maintenance gates are as follows;



There were water leakages from concrete structure of

No.1 stoplog.

There were water leakages from concrete structure of

No.2 stoplog.

The rubber seal had been damaged.

The stoplog gate leaf was in sound condition.

Gantry crane was deteriorated because of aging.

The bearing was making noise during the move of gantry

crane.

The penstock gate gate leaf.




The inside of local control panel is in bad condition

because of humidity and small animals.

The remote control was out of service.

Photo 8.1-23 Conditions of Penstock Gates and Maintenance Gates (Stoplog)



Identification of Rehabilitation Items

Based on the result of site investigation, the necessity of rehabilitation for gate and penstock facilities are decided as showed in Section 8.2.1 and Section 8.2.2. In addition to the necessity, the urgency is added in the tables and the urgency is considered as follows:

Urgency I : Urgent “Urgent” is considered to be critical for the operation. The failure on these

facilities can force the powerhouse to shut down immediately.

Urgency II : Moderate “Moderate” is not considered to be critical but have some practical impacts on the operation. In addition, some items of “Urgent” are considered as “Moderate” because of the low potential of serious failure (ex. penstock, surge tank).

Urgency III : Minor “Minor” is considered to have no practical impact on the operation.


The necessity of rehabilitation for gate and penstock facilities in Baluchaung No.1 HPP is showed in the following tables from Table 8.2-1 to Table 8.2-6.

The following facilities are not included in the Project;

- Mobye Dam Irrigation Gate

Table 8.2-1 Screening List for Baluchaung No.1 HPP - Intake Dam

Hydropower Plant Baluchaung No.1

Facilities/Equipment Intake

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Spillway Facilities Ⅱ

Spillway Gate Gate Leaf ✓ NA C P

Hoist ✓ ✓ NA B P

Control ✓ ✓ NA ✓ A R

Stop Log Gate Leaf ✓ ✓ NA C P

Hoist ✓ ✓ NA B R

Intake Facilities Ⅰ

Intake Gate Gate Leaf ✓ ✓ NA B P



Remote Control ✓ ✓ NA ✓ A R

Stop Log Gate Leaf ✓ NA C P

Raking System Ⅱ

Raking System Trashrack ✓ NA C P

Power Unit ✓ ✓ NA B P

Control ✓ ✓ NA ✓ B R

Malfunction of the control leads to failure of water supply to Baluchaung system.



*3 Measures R :Replacement P :Repair A :Addition I :Inspection

Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3 Remarks

Urg

ency

*4

*1 Check items✓ :Problem NA :Not available blank: No problem

*2 Screening for the RehabilitationProject A :Required B :Recommended C :Not Required

*4 Urgency Ⅰ: Urgent Ⅱ: Moderate Ⅲ: Minor



Table 8.2-2 Screening List for Baluchaung No.1 HPP - Head Pond

Table 8.2-3 Screening List for Baluchaung No.1 HPP - Steel Pipe


Facilities/Equipment Head Pond

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Inlet Facilities Ⅰ

Inlet Gate Gate Leaf ✓ NA C P



Sand Flash Ⅱ

Main Valve Gate Leaf NA NA NA B I

Hoist NA NA NA A R


Guard Valve Gate Leaf NA NA NA B I

Hoist NA NA NA B I

Raking System Ⅲ

Raking System Trashrack ✓ NA C P

Power Unit ✓ ✓ NA B P






Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3

Urg

ency

*4


Remarks

Further inspection is necessary (smooth operation and water tightness of the gate)

It is necessary to flash the sediments.

It is necessary to flash the sediments, it is common with guard valve

Further inspection is necessary (smooth operation and water tightness of the gate)

Further inspection is necessary (smooth operation of the gate)


Facilities/Equipment Steel Pipe

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

By-pass Valve Ⅱ

By-pass Valve Gate Leaf NA NA C P

Hoist ✓ ✓ NA C R

Steel Pipe Ⅱ

Low Pressure Pipe Line Pipe ✓ NA B P

Support ✓ ✓ NA B P

Expantion Joint ✓ ✓ NA ✓ A R

Penstock Pipe ✓ NA B P

Support ✓ ✓ NA B P

Expantion Joint ✓ ✓ NA ✓ A R

Surge Tank Ⅱ

Surge Tank Structure ✓ ✓ NA B P

Expantion Joint ✓ ✓ NA ✓ C R





Remarks

Urg

ency

*4Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3

To reduce the head loss due to water leakage

To reduce the head loss due to water leakage



Table 8.2-4 Screening List for Baluchaung No.1 HPP - Powerhouse

Table 8.2-5 Screening List for Baluchaung No.2 HPP - Headrace Channel Gate


Facilities/Equipment Power House

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Emergency Discharge Valve Ⅰ

Main Valve Valve ✓ ✓ NA B P

Hoist ✓ ✓ NA A R


Guard Valve Gate Leaf NA NA NA B P


Tailrace Gate Ⅰ

Tailrace Gate Gate Leaf ✓ ✓ NA B P






Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3

Urg

ency

*4

Position indicator is necessary to calcurate the amount of discharge water.

Common with guard valve

Remarks

Oil pressure unit is common with main valve


Facilities/Equipment Baluchaung No.2 Headrace Channel

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Baluchaung No.2 Headrace Channel Ⅲ

Upstream Gate Gate Leaf ✓ ✓ NA C P


Downstream Gate Gate Leaf ✓ ✓ NA C P



Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3 Remarks

Urg

ency

*4


*2 Screening for the Rehabilitation Project A :Required B :Recommended C :Not Required




Table 8.2-6 Screening List for Baluchaung No.1 HPP - Mobye Dam


The necessity of rehabilitation for gate and penstock facilities in Sedawgyi HPP is showed in Table 8.2-7 and Table 8.2-8.

The following facilities are not included in the Project;

- Sedawgyi Dam Spillway Spillway Gate Spillway Stoplog

Irrigation Irrigation Gate Irrigation Stoplog

Penstock Gate Stoplog

Screening of Existing Facilities/Equipment for the Rehabilitation Project


Facilities/Equipment Mobye Dam

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Spillway Facilities Ⅰ

Spillway Gate Gate Leaf ✓ ✓ NA B P


Local Control ✓ ✓ NA ✓ A R


Stop Log Gate Leaf ✓ ✓ NA B P

Navigation Gate Facilities Ⅲ

Navigation Gate Gate Leaf ✓ ✓ NA B P

Hoist ✓ ✓ NA A P


House ✓ ✓ NA ✓ A R

Stop Log Gate Leaf ✓ ✓ NA B P

Irrigation Gate Facilities Ⅲ

Irrigation Gate Gate Leaf ✓ ✓ NA B P



Guard gate Gate Leaf ✓ ✓ NA B P


Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3 Remarks

Urg

ency

*4




Malfunction of the gates does not affect to w ater supply to Baluchaung system. Out of scope.

ditto

Out of scope

Malfunction of the gate leads to failure of water supply to Baluchaung system.



Out of scope

Malfunction of the gates does not affect to w ater supply to Baluchaung system. Out of scope.

ditto

ditto



Table 8.2-7 Screening List for Sedawgyi HPP - Powerhouse

Table 8.2-8 Screening List for Sedawgyi HPP - Dam Facilities

Hydropower Plant Sedawgyi

Facilities/Equipment Power House

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Draft Tube Gate Ⅰ

Draft Tube Gate Gate Leaf ✓ ✓ NA C P

Gantry Crane Structure ✓ ✓ NA B P


Control ✓ ✓ NA B R

Penstock Ⅰ

Penstock Pipe NA NA NA C P


Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3 Remarks

Urg

ency

*4




Hydropower Plant Sedawgyi

Facilities/Equipment Dam

aged

dete

riora

tion

appa

rent

insp

ectio

n

trou

ble

reco

rd

avai

rabi

lity

ofsp

are

part

s

Spillway Facilities Ⅱ

Spillway Gate Gate Leaf ✓ NA C P

Hoist ✓ ✓ NA ✓ A R


Stop Log Gate Leaf ✓ ✓ NA C P

Penstock Gate Facilities Ⅰ

Intake Gate Gate Leaf ✓ ✓ NA B R




Stop Log Gate Leaf ✓ NA A P

Gantry Crane ✓ NA B I

Irrigation Gate Facilities Ⅲ

Irrigation Gate Gate Leaf NA NA NA B P



Guard Gate Gate Leaf ✓ ✓ NA B P



Replace


ditto

Malfunction of the gate affects the rehabilitation work and safety of HPP.

Malfunction of the gate affects the rehabilitation work and safety of HPP.

ditto

ditto

Malfunction of the gate affects the rehabilitation work. Out of scope.

Malfunction of the control affects the rehabilitation work and safety of HPP.

Replace of rubber seal. Out of scope.

ditto

ditto

ditto

Out of scope

Malfunction of the gate affects the dam safety. Out of scope.

Malfunction of the control affects the dam safety. Out of scope.

Out of scope


Components

App

licat

ion

Check item *1

Scre

enin

g*2

Mea

sure

s*3 Remarks

Urg

ency

*4*1 Check items✓ :Problem NA :Not available blank: No problem




Basic Design on Rehabilitation of Gates and Penstock


The rehabilitation items in Baluchaung No.1 HPP are listed below. Through the discussion between EPGE (Electric Power Generation Enterprise) and JICA Survey Team, it was concluded that minor failures on control panels (local and remote) that is not mentioned below shall be fixed by EPGE because it is available in Myanmar.

(1) Intake Dam


5 position meters for the spillway gates shall be provided. The position meter shall be equipped with the A/D convertor (4 digits). To omit the replacement of the cables between the meter and remote control panel, similar model shall be applied.

Fig. 8.3-1 Intake Dam Spillway Gate Position Indicator

2) Intake Gate and Stoplog

4 A/D convertors shall be provided. On the other hand, adjusting is enough to fix the problem on position meter at the hoist.



Fig. 8.3-2 Intake Dam Intake Gate Position Meter Convertor

3) Raking System

No need to be rehabilitated.

4) Remote Control

12 position indicators (4 digits) shall be provided. 3 of 12 shall be provided as spare parts.

(2) Head Pond

1) Inlet Gate


2) Sand Flash Gate

The hoist of main valve shall be replaced.



Fig. 8.3-3 Procurement List for Baluchaung No.1 HPP

3) Raking System


(3) Low Pressure Pipe Line, Surge Tank and Penstock

1) By-pass Valve


2) Low Pressure Pipe Line

10 seals for expansion joint shall be provided.



Fig. 8.3-4 Low Pressure Pipe Line Replacement of Joint Seal

3) Surge Tank


4) Penstock

1 seal for expansion joint shall be provided.



Fig. 8.3-5 Penstock Replacement of Joint Seal

(4) Emergency Discharge Valve

1) Main Valve

Consumable materials indicated in Fig. 8.3-6 shall be provided.



Fig. 8.3-6 Procurement List for Emergency Discharge Valve

2) Guard Valve


3) Others


(5) Tailrace Gate


(6) Baluchaung No.2 HPP - Haedrace Channel Gate

1) Upstream Gate


2) Downstream Gate


(7) Mobye Dam

MOEE has another plan of rehabilitation of Mobye dam. Therefore, no need to be rehabilitated.



(8) Rehabilitation without supervising service

EPGE have continued to implement the maintenance and repair works for gate and penstock facilities since the commissioning. Based on the discussion with EPGE, following items will be procured by the Project but being installed by EPGE without supervising service by the Consultants.

Table 8.3-1 Procurement List for Baluchaung No.1 HPP

Location Facility Item Qty Specifications, notes

Intake Dam Spillway Gate Position meter 5 Type: Stand type Hoisting Stroke: 7.5m Output: BCD (4digits)

Intake Gate A/D converter 7 Product: ARC-4D-101 (Nippon Electric Industry Co., Ltd) 4 for replace, 3 for spare parts

Remote Control Panel

Digital Indicator 12 Product: LED-N-B264-AC (Nippon Electric Industry Co., Ltd) 9 for replace, 3 for spare parts

Low Pressure Pipe Line

Expansion Joint Seal 10 Inner diameter: 4,100mm Material: Rubber, Greased graphite Diameter: 22mm

Penstock Expansion Joint Seal 1 Inner diameter: 3,800mm Material: Rubber, Greased graphite Diameter: 22mm

Power House Emergency Discharge Valve

Hoist 1 Position meter (Messenger wire type)

Consumable Materials

1 set 3 U Packings Size: φ640/φ600*30H Material: Synthetic rubber

1 Dust Seal Size: φ620/φ600*10H Material: Felt

“O” Rings (4 in total) Size: φ8.4 ID: 665.7mm, 545.7mm, 675.5mm and 1195.5mm

Material: Synthetic rubber Mobye Dam Spillway Gate Hoist (Motor) 4 Type: Brake Motor

Capacity: 5.5kW Torque: 50N・m R.P.M.: 945r/min

(9) Rehabilitation with supervising service

The following items shall be replaced under the supervision service by the Consultants;

Table 8.3-2 Replacement List for Baluchaung No.1 HPP


Head Pond Sand Flash Gate Main Valve Hoist 1 Gate Type: High pressure slide gate Hoist Type: Motor powered spindle type Design Head: 13.8m Hoisting Stroke: 0.85m Operating Time 3.0min to 5.0 min




The rehabilitation items in Sedawgyi HPP are listed below.

(1) Power House Facilities

1) Draft Tube Gate


2) Penstock


(2) Dam Facilities


No need to be rehabilitated. The current failures of the spillway gates will be fixed by ID. But it shall be noted that the spillway gate shall be maintained by ID properly because it affect the dam safety.

2) Irrigation Gate and Guard Gate

Out of scope of this project. The irrigation gate shall be maintained by ID.

3) Penstock Gate and Maintenance Gate (Stoplog)

The penstock gate shall be rehabilitated but the stoplog shall be rehabilitated by ID.

The rehabilitation items are 2 sets of gate leaf, guide frame, hoist and local control panel. The remote control function shall be included in the control system at the power plant.

The major premises of this rehabilitation are the dry condition for the penstock gate. According to the interview at the time of site investigation, ID has a plan to fix the water leakage from stoplogs. In addition, at the stage of detailed design, actual condition of civil structures, gate leaves and guide frames shall be surveyed to provide accurate drawings to the Contractor because the as-built drawings and calculation sheets are not available.

(3) Rehabilitation Item for Sedawgyi

The following items shall be replaced under the supervision service by the Consultants;



Table 8.3-3 Rehabilitation List for Sedawgyi HPP


Sedawgyi Dam Penstock Gate Gate leaf 2 Type: Fixed Roller Type Clear Span: 11ft 7in Clear Height: 22ft 13

4 in

Design Water Level: EL. 425.000ft Operating Water Level: EL. 425.000ft

Guide Frame 2 Sill Level: EL. 334.093 ft Height: EL. 391.500 ft Including replacing the concrete structure.

Hoist 2 Type: Oil Pressure Cylinder Type Operating Speed:

- Opening 20 min - Close without pressure 90 sec

Operating Capacity: 50.0 tonf Local Control Panel 2

Chapter 9 Final Report Rehabilitation of Civil Facilities


CHAPTER 9

REHABILITATION OF CIVIL FACILITIES



Chapter 9 Rehabilitation of Civil Facilities

Method, Results of Site Reconnaissance and Issues

JICA (Japan International Cooperation Agency) Survey Team carried out the site reconnaissance of civil facilities regarding Baluchaung No.1 HPP (Hydropower Plant) and Sedawgyi HPP during their second site investigation in February 2016 and also fourth site investigation in June 2016 as a supplemental study. Visual inspection, measurement (crack, leakage, etc.), interview to officials in charge are used for the inspection.

9.1.1 Baluchaung No.1 HPP

Site reconnaissance of civil facilities at Baluchaung No.1 HPP and related facilities (refer to Fig. 9.1-1) was carried out based on check sheets as attached in Annex 9.

Overall, most of civil facilities such as concrete structures and embankments are stable and in good conditions. However, some observation equipment such as water level gauges installed to civil facilities are mostly not functioned properly due to aged deterioration.

Fig. 9.1-1 Location Map of Civil Facilities for Site Reconnaissance

at Baluchaung No.1 HPP and related Facilities

(1) Dawtacha Intake Dam

Nam Pawn River Thanlwin River

Inle Lake

Mobye Reservoir

(2) Headrace Channel

(3) Regulation Pondage

(4) Low Pressure Pipe Line

(5) Surge Tank

(6) Penstock

(7) Powerhouse

(8) Mobye Dam

(9) Loikaw City Gauging Station

Baluchaung No.1 HPP

Baluchaung No.2 HPP

Baluchaung No.3 HPP

Chapter 9 Rehabilitation of Civil Facilities Final Report


(1) Dawtacha Intake Dam

1) Main Dam (Embankment)

Generally main dam was maintained in good condition. However, regarding the layout of security tower installed to the downstream slope after the commencement of commercial operation, relocation to out of slope is recommended from the view point of dam stability.

Photo 9.1-1 Main Dam (Embankment)

2) Spillway and Intake

Regarding the concrete structures of spillway and intake, no serious problem was found.

Photo 9.1-2 Spillway (Back) and Intake (Near)

3) Others

Three (3) water level gauges and one (1) rain gauge installed at DTC (Dawtacha Intake Dam) are recommended to replace due to aged deterioration. Especially water level gauge installed for the downstream apron of spillway is deteriorated and transmits abnormal value to the display panel at control station.

Regarding the VHF (Very High Frequency) radio telephone equipment installed as communication system between DTC and three (3) facilities such as Powerhouse (BHP1), Mobye Dam (MBY) and Loikaw City Gauging Station (LKW), only one (1) channel (DTC-BHP1) is still working and other channels (DTC-MBY and DTC-LKW) are interrupted due to aged deterioration. Currently mobile phone is used for communication between BHP1 and MBY or LKW as an alternative of interrupted channels. In case of rehabilitation regarding the above-mentioned communication system, appropriate communication technology, which is a



constantly advancing field, shall be studied by communication expert (refer to Chapter 10).

Lastly EDG (Emergency Diesel Generator) of 50kVA was deteriorated, replacement is recommended for emergency operation.

Photo 9.1-3 Water Level Gauges Installed at Dawtacha Intake Dam


1) Waterway

Waterway was maintained in good condition.

Photo 9.1-4 Waterway

2) Side Spillway

Photo 9.1-5 Side Spillway



No serious problem was found at the side spillway, which is located at around 1 km downstream from Dawtacha Intake Dam.

(3) Regulation Pondage

1) Pondage

Pondage was maintained in good condition.

Photo 9.1-6 Pondage

2) Siphon Spillway

Siphon spillway was operated to supply stored water to Baluchaung River for hydropower generation of Baluchaung No.2 HPP during complete stoppage sequence of Baluchaung No.1 HPP on February 2, 2016. It functioned properly and no find out serious problem.

Photo 9.1-7 Siphon Spillway (Left: No Operation, Right: In Operation)

3) Others

Two (2) water level gauges installed at pondage were removed due to aged deterioration and water level is currently measured by visual observation of staff gauge. Originally observed data of water levels at the upstream of inlet gate was sequentially transmitted and recorded by control equipment at powerhouse because management of stored water at pondage is quite important for hydropower generation of Baluchang No.1 HPP. Therefore rehabilitation of water level observation instruments and data transmission system between pondage and powerhouse is highly recommended.



Exterior of water level gauges. Interior of water level gauge (instrument was partly

removed).

Photo 9.1-8 Water Level Gauges Installed at Regulation Pondage

In addition fence around the pondage was partly damaged at three (3) points. As primary school is located nearby, children are easily access to the pondage. Therefore urgent repair work by EPGE (Electric Power Generation Enterprise) to avoid an accident causing injury or death is recommended.

Photo 9.1-9 Damaged Fence around the Pondage

(4) Low Pressure Pipe Line

Regarding the anchor blocks and saddle piers of low pressure pipe line, no serious problem was found.

Photo 9.1-10 Low Pressure Pipe Line



(5) Surge Tank

Regarding the concrete structure of surge tank, no serious problem was found.

Photo 9.1-11 Surge Tank

(6) Penstock

Regarding the anchor blocks and saddle piers of penstock, no serious problem was found.

Photo 9.1-12 Penstock

(7) Powerhouse

1) Building

Photo 9.1-13 Building and Steel Rolling Door



Generally building was maintained in good condition. However braking system of steel rolling door was broken, therefore replacement is recommended from the security and safety viewpoint.

2) Tailrace

Regarding the concrete structure of tailrace, no serious problem was found. However water level gauge installed to tailrace is recommended to replace due to aged deterioration.

Photo 9.1-14 Tailrace and Installed Water Level Gauge

3) Others

EDG of 150kVA was deteriorated, replacement is recommended for emergency operation.

(8) Mobye Dam (MBY)

1) Main Dam (Embankment)

Fig. 9.1-2 and Table 9.1-1 show typical cross section of Main Dam and salient features of MBY Project, respectively.

Source: DHPI

Fig. 9.1-2 Typical Cross Section of Main Dam



Table 9.1-1 Salient Features of Mobye Dam Project

Source: DHPI

Generally main dam was maintained in good condition and no obvious deformation, crack and leakage was found.

Photo 9.1-15 Main Dam (Left: Upstream Slope, Right: Downstream Slope)

(D/S)STREAM SLOPE 1;2.5



2) Spillway and Navigation Lock

Regarding the concrete structures of spillway and navigation lock, aged deterioration is seemed to be in progress, however, currently no serious problem was found.

Photo 9.1-16 Spillway (Left) and Navigation Lock (Right)

3) Sedimentation

MBY is operated and maintained by DHPI (Department of Hydropower Implementation). According to the interview with officials of DHPI, JICA Survey Team received the following information.

- As most of the sediment supplied from the catchment are trapped at Inle Lake, stored water at Mobye reservoir is very clear and there are no sedimentation issues.

- Therefore DHPI doesn't have a necessity to revise storage capacity curve and still use original one (refer to Fig. 9.1-3).

Source: DHPI

Fig. 9.1-3 Storage Capacity Curve of Mobye Reservoir



4) Others

Water level gauge and rain gauge installed at MBY are recommended to replace due to aged deterioration. Regarding the VHF radio telephone equipment installed as communication system, MBY-DTC channel is interrupted due to aged deterioration as mentioned in 3), (1) of Section 9.1.1.

(9) Loikaw City Gauging Station (LKW)

Water level gauge and rain gauge installed at LKW are recommended to replace due to aged deterioration. Regarding the VHF radio telephone equipment installed as communication system, LKW-DTC channel is interrupted due to aged deterioration as mentioned in 3), (1) of Section 9.1.1.

Photo 9.1-18 Water Level Gauge (Left) and Radio Telephone Equipment (Right)

Installed at Loikaw City Gauging Station

9.1.2 Sedawgyi HPP

Site reconnaissance of civil facilities at Sedawgyi HPP (refer to Fig. 9.1-4) was carried out based on check sheets as attached in Annex 9.

Most of hydraulic gates installed to civil facilities at Sedawgyi HPP are under the jurisdiction of ID (Irrigation Department) of MOALI (Ministry of Agriculture, Livelihood and Irrigation). Some of them have not only minor problems for their long term stability but also rather serious problem for future implementation of rehabilitation works on hydropower generation equipment.

Photo 9.1-17 Water Level Gauge and Rain Gauge Installed at Mobye Dam



Fig. 9.1-4 Location Map of Civil Facilities for Site Reconnaissance at Sedawgyi HPP

(1) Concrete Dam

Reservoir

(2) Earthfill Dam

(3) Rockfill Dam

(4) Spillway

(5) Penstock

(6) Powerhouse

(9) Reservoir

Sedawgyi HPP

(7) Left Saddle Dam

(8) Right Saddle Dam

Bank failure (Photo 9.1-35) Sandbar

(Photo 9.1-39)

Bank failure (Photo 9.1-36)

Japan Gon Village



(1) Concrete Dam

1) Power Dam Section

Fig. 9.1-5 shows the schematic illustration of Sedawgyi HPP. Two (2) intake towers for hydropower generation are located at the upstream of power dam section. As inlet valves are not installed, penstock gates (hydraulic gate) are used for the maintenance of generating equipment and maintenance gates (stoplog) are also installed for the maintenance of penstock gates.

Fig. 9.1-5 Schematic Illustration of Sedawgyi HPP

According to the interview with officials of ID and EPGE, both of penstock gates (unit 1 and 2) were not functioned properly due to leakage problem. Therefore maintenance gates were used for dewatering operation to conduct internal inspection of generating equipment. However, as a result of dewatering operation for unit 1, large amount of leakage was occurred from the breast wall of intake tower and also gate seal of stoplog.

Photo 9.1-19 Leakage at the Intake Tower for Unit 1

(1) Concrete Dam

(2) Earthfill Dam (3) Rockfill Dam

(4) Spillway

(5) Penstock

(6) Powerhouse

Sedawgyi HPP

(7) Left Saddle Dam (8) Right Saddle Dam

Unit 1

Penstock Gate (Downstream) Maintenance Gate (Upstream)

Unit 2 No.1 No.7

Spillway (7 gates)

Irrigation Sluice

Relative Distance (R.D.) 0 R.D. 4,085



Although drainage operation at the bottom of penstock was carried out by hydropower plant personnel, it was difficult to minimize the spilled water for the implementation of internal inspection. After that ID planned to conduct the rehabilitation works of maintenance gate for unit 1 in June 2016, because water level of reservoir seemed to be the lowest in June to July according to historical record.

However, actual water level of reservoir in June 2016 was re-rose and approached to nearly FWL (Full Water Level, refer to Fig. 9.1-6) due to unexpected volume of inflow caused by heavy rain. As a result, ID could not conduct the rehabilitation works of maintenance gate and therefore JICA Survey Team gave up internal inspection for unit 1.

In addition JICA Survey Team could not access to penstock gates for site inspection to confirm the cause of leakage problem due to high water level of reservoir during their fourth site investigation in June 2016.

Fig. 9.1-6 Water Level and Cross Section of Sedawgyi Dam (Concrete Dam Section)

2) Inspection Gallery

As most of observation instruments installed at inspection gallery were deteriorated, it is recommended to conduct repair works by ID. Leakage water is still able to be observed by triangular notch weir, however, periodical measurement is not conducted. According to the interview with officials of ID, sump well (10 feet length, 10 feet depth and 7 feet height) is filled up four (4) times a day, so estimated amount of leakage gathered to sump well is approximately 55 liter/min.

Photo 9.1-20 Observation Instruments Installed at Inspection Gallery (Left: Pendulum, Right: Uplift Pressure Gauge)

320

330

340

350

360

370

380

390

400

410

420

430Water Level of Sedawgyi Dam

FWL 419.50 feet (127.86 m)

MDDL 365.00 feet (111.25 m)

Spillway Gate

Penstock Gate

Maintenance Gate(Stoplog)

andConcrete Crack

Wat

er L

evel

(feet

)Power Dam Section

Overflow Section



3) Others

Regarding non overflow section and dam crest, no serious problem was found.

Photo 9.1-21 Non Overflow Section (Left) and Dam Crest (Right) of Concrete Dam

(2) Earthfill Dam

1) Downstream Slope

Partly gullies were found to the downstream slope of earthfill dam. It is recommended to conduct repair works by ID.

No leakage was observed at the measurement weir which located at the downstream toe of earthfill dam as of February 18, 2016.

Photo 9.1-22 Gullies at the Downstream Slope

of Earthfill Dam Photo 9.1-23 Measurement Weir

as of February 18, 2016

Regarding the observation house located at around R.D. 1 1,605 ~ 1,615, piezometer observation has been abandoned and spilled water erodes the downstream slope. It is recommended that spilled water shall be bypassed to the downstream toe by appropriate way not to erode the downstream slope and eroded slope shall be backfilled by ID according to the original design.

1 Relative distance in feet from the left bank end of Sedawgyi Dam (refer to Fig. 9.1-5).



Photo 9.1-24 Current Situation of Observation House and Eroded Slope

2) Others

Some minor slope failures were found at the upstream slope of earthfill dam. It is recommended to conduct repair works by ID. Regarding dam crest, no serious problem was found.

Photo 9.1-25 Upstream Slope (Left) and Dam Crest (Right) of Earthfill Dam

(3) Rockfill Dam

Some minor slope failures were found at the upstream slope of rockfill dam. It is recommended to conduct repair works by ID.

Photo 9.1-26 Upstream Slope Rockfill Dam

Regarding downstream slope and dam crest, no serious problem was found.



Photo 9.1-27 Downstream Slope (Left) and Dam Crest (Right) of Rockfill Dam

(4) Spillway

According to salient features of Sedawgyi Dam Project, design flood discharges, outflow through spillway and parameters of spillway are shown below.

- Design Flood Discharges 1 in 10 years : 145,000 cusecs (4,105.94 m3/s) 1 in 100 years : 168,000 cusecs (4,757.23 m3/s) 1 in 1,000 years : 235,000 cusecs (6,654.46 m3/s) 1 in 10,000 years : 300,000 cusecs (8,495.05 m3/s)

- Outflow (through Spillway) at FWL* with 6 gates : 235,500 cusecs (6,668.62 m3/s) in operation * FWL = EL. 419.50 feet (127.86 m)

- Spillway Length of concrete : 360 feet (109.73 m) spillway Crest level of spillway : EL. 384.50 feet (117.20 m) Number and size of : 7 of 40 feet (12.19 m) wide ∗ 36.5 feet (11.13 m) high spillway radial gates

However, according to the interview with officials of ID and EPGE, No.1 and No.7 of spillway gates (refer to Fig. 9.1-5) were not able to fully open due to jamming or other reasons and current gate opening of 2 gates is about 15 feet (4.57 m). Therefore pre-release operation has been temporally adopted to Sedawgyi Dam just before entering wet season to increase a storage volume below crest level for flood control.

Although the maximum experienced flood of Sedawgyi Dam after the commencement of commercial operation is 90,720 cusecs (2,568.90 m3/s) on August 15, 1992, flood control operation is one of the most important function for dam safety. Therefore decrease in discharging capacity caused by failure/trouble shall be recovered by ID as soon as possible.

In June 2016, JICA Survey Team carried out their fourth site investigation and received the following information from ID's office in Mandalay.

- Spillway gate No.7 was checked and repaired by ID in June 2016.



- Spillway gate No.1 still have a gate opening problem (6.5 feet is maximum) but will be repaired after rainy season.

- Currently 6 gates (No.2 to No.7) are able to fully open and have enough discharging capacity for designed flood operation.

Photo 9.1-28 Spillway Gates (Left) and Gate No.7 (Right)

(5) Penstock

At the penstock encased with concrete, exposed reinforcing bars were found by NEWJEC engineers in January 2014, therefore repair works was recommended at that time to stop further corrosion of the reinforcing bars (refer to Photo 9.1-29).

Source: Site Visit Report, NEWJEC, January 2014

Photo 9.1-29 Exposed Reinforcing Bars at Penstock as of January 2014

During second site investigation in February 2016, JICA Survey Team found that repair works was completed based on the recommendation.

No.1 No.7



Photo 9.1-30 Current Situation of Penstock as of February 2016

(6) Powerhouse

1) Building

Generally building was maintained in good condition. However some cracks are found around the penstock at B3 floor.

Photo 9.1-31 Cracks around the Penstock

2) Tailrace

Regarding the concrete structure of tailrace, no serious problem was found.

3) Others

Two (2) water level gauges installed near the intake gate and tailrace gate, which are under the jurisdiction of ID, are deteriorated and transmit abnormal value to the display panel at control station of powerhouse. As a result, water levels at the intake and tailrace are currently measured by visual observation of staff gauge. However, for efficient hydropower generation by Kaplan turbine, sequential observation of water level is

Photo 9.1-32 Tailrace



required. Therefore it is recommended to EPGE that additional installation of automatic water level observation instruments at the intake and tailrace for hydropower generation.

(7) Left Saddle Dam

Eroded spot caused by heavy rain was found at the downstream side of dam crest. It is recommended to conduct repair works by ID.

Regarding upstream slope and downstream slope, no remarkable problem was found.

(8) Right Saddle Dam

There is a small village near the right saddle dam. Villagers reclaimed the upstream slope for their utilization as boatslip without any permission from ID. Therefore ID once excavated the reclaimed ground four (4) years ago to rehabilitate this area based on the design drawing, however, villagers refilled there again. Also villagers sometime take away riprap stones for their own use or other reasons.

Right shoulder of dam crest was scraped away caused by three-point turn of automobile in wet season. It is recommended to conduct repair works by ID.

Regarding downstream slope, no serious problem was found.

Photo 9.1-34 Upstream Slope (Left) and Dam Crest (Right) of Right Saddle Dam

(9) Reservoir

1) Watershed

JICA Survey Team conducted site reconnaissance for the reservoir and upstream reaches of Chaungmagyi River by boat together with the officials of ID and EPGE on February 24, 2016. Remarkable deforestation and/or land slide were not found from the latest satellite image as shown in Fig. 9.1-4 and then confirmed by visual observation. Through the site reconnaissance, two (2) bank failures were observed at the left side of reservoir (at around 4.1 km upstream from Sedawgyi Dam) and at the left side bank of Chaungmagyi River (at around 16 km upstream from Sedawgyi Dam and 2.7 km upstream from Japan Gon Village), however, remarkable deforestation and/or land slide were not found.

Photo 9.1-33 Eroded Spot at Dam Crest of Left Saddle Dam



Photo 9.1-35 Bank Failure at the Left Side

of Reservoir Photo 9.1-36 Bank Failure at the Left Side Bank of Chaungmagyi River

2) Sedimentation

According to the Site Visit Report (hereinafter referred to as "NEWJEC Report") made by NEWJEC engineers and submitted to ID and EPGE in January 2014, sedimentation issues at Sedawgyi Dam are the following.

- At the time of site visit to the upstream area of Sedawgyi reservoir in May 2012, flow depth at the upstream end of the reservoir became too shallow to go through by an engine boat, and assistance was needed to draw the boat piling up on the sediment (refer to Photo 9.1-37). At the end of the reservoir after passing Japan Gon Village, 3 to 4 m high sandbars on the both sides were seen (refer to Photo 9.1-38).

- According to the Sedawgyi Sedimentation Report (hereinafter referred to as "ID Report") made by Design Branch of ID and submitted to the main office of ID in October 2013, it was concluded that no removal of sediment in the reservoir was necessary. And ID Report suggested that cooperation with related authorities* was essential to reduce the sedimentation. Furthermore, ID Report suggested that the irrigation outlet should be opened and closed regularly for reducing sedimentation, and reservoir regulation should comply with an operation manual.

* Such as Forest Department of MOECAF (Ministry of Environmental Conservation and Forestry)



Photo 9.1-37 River Condition just before Japan Gon Village as of May 28, 2012

Photo 9.1-38 Right Bank View Upstream of Japan Gon Village as of May 28, 2012

- According to the ID report, sedimentation survey after the commencement of commercial operation was conducted twice in 2002 and 2013. Based on survey result, stage storage



capacity area curves (H-V-A curve) of the original, 2002 and 2013 were drawn (refer to Fig. 9.1-7). These curves appear to be strange, but if the curves of the original year could be eliminated, figure would look natural, in other words, the curves of 2002 and 2013 show the progress on accumulation of reservoir sedimentation.


Fig. 9.1-7 Stage Storage Capacity Area Curves of Sedawgyi Reservoir

Based on the above-mentioned data and information, JICA Survey Team interviewed to the officials of ID (Sedaw office and Mandalay office) and conducted site reconnaissance by boat to grasp the current situation and additional information regarding the sedimentation issues at Sedawgyi Dam.

As a result of site reconnaissance by boat, river condition around Japan Gon Village was not so serious and water depth was enough for engine boat although one sandbar was seen.

According to the officials of ID, latest sedimentation survey was conducted in 2013 and cross sections for sedimentation survey was shown in Fig. 9.1-4.

Although the stage storage capacity area curves of the original, 2002 and 2013 were drawn, ID still uses the original curve for their calculation. ID doesn't have any plan for sedimentation countermeasures of Sedawgyi Dam based on the conclusion of ID Report.

45 40 35 30 25 20 15 10 5 0

85

90

95

100

105

110

115

120

125

130

135

0 50 100

150

200

250

300

350

400

450

500

550

600

650

700

Rese

rvoi

r WL

(EL.

m)

Capacity (million m3)

Reservoir Area (km2)

Capacity (Original) Capacity (2013) Capacity (2002)

Area (Original) Area(2013) Area (2002)

Photo 9.1-39 Sandbar Located Around Japan Gon Village as of February 24,

2016



Identification of Rehabilitation Items

Based on the result of site investigation, the necessity of rehabilitation for civil facilities are decided as showed in Sections 9.2.1 and 9.2.2. In addition to the necessity, the urgency is added in the tables and the urgency is considered as described in Section 8.2 of Chapter 8.


Regarding civil facilities, no item was listed in the application for rehabilitation work of Baluchaung No.1 HPP, however, based on the result of site reconnaissance as described in Section 9.1.1, it is recommended to replace or repair some items listed in Table 9.2-1.

Table 9.2-1 Screening Result of Civil Facilities at Baluchaung No.1 HPP for the Rehabilitation Project

Hydropower Plant Baluchaung No.1 *1 Check items ✓ :Problem NA :Not available blank: No problem



*4 Urgency I :Urgent II :Moderate III :Minor

Facilities/Equipment Civil Facilities

aged

det

erio

rati

on

app

aren

tin

spec

tio

n

tro

ub

le r

eco

rd

avai

lab

ility

of

spar

e p

arts

(1) Dawtacha Intake Dam (DTC)

Main Dam (Embankment) NA NA CSpillway and Intake NA NA COthers Spillway NA NA A R II

Headrace NA NA A R IIReservoir NA NA A R II

Rain gauge NA NA A R III

DTC-BHP1 NA NA B R III In case of rehabilitation, appropriate technologyshall be studied by communication expert.

DTC-MBY NA NA B R III ditto

DTC-LKW NA NA B R III ditto

Emergency Diesel Generator NA NA A R I(2) Headrace Channel

Waterway NA NA CSide Spillway NA NA C

(3) Regulation Pondage (PDG)

Pondage NA NA CSiphon Spillway NA NA COthers Upstream #1 NA NA A R I

Upstream #2 NA NA A R I

Fence around the pondage NA NA B P III Urgent repair work is recommended to becarried out by EPGE.

Communication system PDG-BHP1 NA NA A R I(4) Low Pressure Pipe Line NA NA C(5) Surge Tank NA NA C(6) Penstock NA NA C

Water level gauge

Communication system

Water level gauge

Components

Ap

plic

ati

on

Check item *1

Sc

ree

nin

g*2

Urg

en

cy*4 Remarks

Me

as

ure

s*3



9.2.2 Sedawgyi HPP

Regarding civil facilities, no item was listed in the application for rehabilitation work of Sedawgyi HPP, however, based on the result of site reconnaissance as described in Section 9.1.2, it is recommended to replace or repair some items listed in Table 9.2-2.

aged

det

erio

rati

on

app

aren

tin

spec

tio

n

tro

ub

le r

eco

rd

avai

lab

ility

of

spar

e p

artsComponents

Ap

plic

ati

on

Check item *1

Sc

ree

nin

g*2

Urg

en

cy*4 Remarks

Me

as

ure

s*3

(7) Powerhouse (BHP1)

Building NA NA CTailrace NA NA COthers Water level gauge Tailrace NA NA A R I

Communication system BHP1-DTC NA NA B R III In case of rehabilitation, appropriate technologyshall be studied by communication expert.

Steel Rolling Door NA NA A R IIIEmergency Diesel Generator NA NA A R I Refer to "Relevant Substation and TL Facilities"

(8) Mobye Dam (MBY)

Main Dam (Embankment) NA NA CSpillway and Navigation Lock NA NA COthers Water level gauge NA NA A R II

Rain gauge NA NA A R III

Communication system MBY-DTC NA NA B R III In case of rehabilitation, appropriate technologyshall be studied by communication expert.


Others Water level gauge NA NA A R IIRain gauge NA NA A R III

Communication system LKW-DTC NA NA B R III In case of rehabilitation, appropriate technologyshall be studied by communication expert.



Table 9.2-2 Screening Result of Civil Facilities at Sedawgyi HPP for the Rehabilitation Project

Hydropower Plant Sedawgyi *1 Check items ✓ :Problem NA :Not available blank: No problem





aged

det

erio

rati

on

app

aren

tin

spec

tio

n

tro

ub

le r

eco

rd

avai

rab

ility

of

spar

e p

arts

(1) Concrete DamDam body NA NA C

Breast wall NA NA A P I Urgent repair work will be carried out by ID in June 2016.Stoplog groove NA NA CGate groove NA NA NA B P I Site inspection shall be conducted in 2017.Breast wall NA NA CStoplog groove NA NA CGate groove NA NA NA B P I Site inspection shall be conducted in 2017.

Overflow Section Refer to "(4) Spillway"Non Overflow Section NA NA CDam Crest NA NA C

Observation instruments NA NA B R III Recommended to be rehabilitated by ID.Drainage pump NA NA B R III ditto

(2) Earthfill DamUpstream Slope NA NA B P III Recommended to be rehabilitated by ID.Downstream Slope NA NA B P II dittoDam Crest NA NA C

(3) Rockfill DamUpstream Slope NA NA B P III Recommended to be rehabilitated by ID.Downstream Slope NA NA CDam Crest NA NA C

(4) SpillwayInlet NA NA CSpillway Crest NA NA CChute NA NA CEnergy Dissipator (Apron) NA NA C

(5) Penstock NA NA C(6) Powerhouse

Building NA NA CTailrace NA NA C

Others Reservoir NA NA A A II For efficient hydropower generation, additional installation isrecommended.

Tailrace NA NA A A II ditto(7) Left Saddle Dam

Upstream Slope NA NA CDownstream Slope NA NA CDam Crest NA NA B P III Recommended to be rehabilitated by ID.

(8) Right Saddle DamUpstream Slope NA NA B P III Recommended to be rehabilitated by ID.Downstream Slope NA NA CDam Crest NA NA B P III Recommended to be rehabilitated by ID.

(9) ReservoirWatershed NA NA CSedimentation NA C

Spillway gate No.1 and No.7 had a gate opening problem,however, No.7 was checked and repaired by ID in June 2016.Therefore repair work of spillway gates is out of futurerehabilitation menu because 6 gates (No.2 to No.7) are ableto fully open and have enough discharging capacity fordesigned flood operation.

Components

Ap

plic

ati

on

Check item *1

Sc

ree

nin

g*2

Me

as

ure

s*3 Remarks

Urg

en

cy*4

Water levelgauge

Intake tower(unit 1)


PowerDamSection

InspectionGallery



Basic Design on Rehabilitation of Civil Facilities


(1) Item for Basic Design

According to the screening result of "A" and "B" listed in Table 9.2-1, EPGE and JICA Survey Team had a series of discussions from May to September 2016 regarding the target facilities/equipment of Baluchaung No.1 HPP to be rehabilitated.

Finally EPGE and JICA Survey Team decided and agreed the rehabilitation item of civil facilities for Baluchaung No.1 HPP as shown in Table 9.3-1.

Table 9.3-1 Agreed Civil Facilities at Baluchang No.1 HPP for the Rehabilitation Project Hydropower Plant Baluchaung No.1 *1 Screening for the

Rehabilitation Project A :Required B :Recommended C :Not Required




Scre

enin

g*1

Mea

sure

s*2

Urg

ency

*3

(1) Dawtacha Intake Dam (DTC)

Main Dam (Embankment) CSpillway and Intake COthers Spillway A R II No, not replace (use staff gauge) No replace

Headrace A R II Yes, replace To be replacedReservoir A R II Yes, replace To be replaced

Rain gauge A R III No, not replace No replaceDTC-BHP1 B R III No, not replace To be replaced (refer to Chapter 10)DTC-MBY B R III No, not replace To be replaced (refer to Chapter 10)DTC-LKW B R III No, not replace No replace

Emergency Diesel Generator A R I No, not replace (transfer existing one) No replace


Waterway CSide Spillway C

(3) Regulation Pondage (PDG)

Pondage CSiphon Spillway COthers Upstream #1 A R I Yes, replace (no need communication) To be replaced (stand-alone type)

Upstream #2 A R I No, not replace No replaceFence around the pondage B P III Repaired by EPGE's budgetCommunication system PDG-BHP1 A R I No, not replace No replace

(4) Low Pressure Pipe Line C(5) Surge Tank C(6) Penstock C(7) Powerhouse (BHP1)

Building CTailrace COthers Water level gauge Tailrace A R I No, not replace (use existing one) No replace

Communication system BHP1-DTC B R III No, not replace To be replaced (refer to Chapter 10)Steel Rolling Door A R III No, not replace No replace

Emergency Diesel Generator A R I Yes, replace (300kVA) To be replaced (refer to Chapter 7)

Final DecisionEPGEApproval

Screening Result

Components

Water level gauge

Communication system

Water level gauge



In the table, hatched item are considered for basic design, however, EDG of powerhouse is described in Chapter 7 and communication facilities are described in Chapter 10.

(2) Water Level Gauge

According to Table 9.3-1, five (5) water level gauges as shown below are agreed for the replacement. In addition three (3) sets of water level gauges will be prepared as spare parts. Considering the exchangeability, transistor pressure type is adopted for all water level gauges including those as spare parts.

1) Dawtacha Intake Dam (DTC)

a) Headrace

Type: Transistor Pressure Type

Measuring Range: EL.868.00 m to EL.873.00 m (5.00 m)

Observation Point: Dawtacha Control Station (Cable Length: 100 to 120 m)

Display: 5 digits (Ex. 870.02)

b) Reservoir



Observation Point: Dawtacha Control Station (Cable Length: 30 to 50 m)


2) Regulation Pondage (PDG)

a) Upstream #1



Scre

enin

g*1

Mea

sure

s*2

Urg

ency

*3

Final DecisionEPGEApproval

Screening Result

Components

(8) Mobye Dam (MBY)

Main Dam (Embankment) CSpillway and Navigation Lock COthers Water level gauge A R II Yes, replace To be replaced

Rain gauge A R III Yes, replace To be replacedCommunication system MBY-DTC B R III No, not replace To be replaced (refer to Chapter 10)


Others Water level gauge A R II No, not replace To be replacedRain gauge A R III No, not replace No replaceCommunication system LKW-DTC B R III No, not replace To be replaced (refer to Chapter 10)

(10) Spare PartsWater level gauge To be prepared (3 sets)



Observation Point: Valve House (Cable Length: 20 to 30 m)


3) Mobye Dam (MBY)



Observation Point: Remote Control Station (Cable Length: 70 to 80 m)


4) Loikaw City Gauging Station (LKW)



Observation Point: Observation House (Cable Length: 40 to 60 m)


(3) Rain Gauge

According to Table 9.3-1, one (1) rain gauge as shown below is agreed for the replacement.

1) Mobye Dam (MBY)

Type: Tipping Bucket Type

Measuring Range: 000.0 mm to 999.5 mm

(4) Deselected Item

According to Table 9.3-1, below item are deselected from the rehabilitation item as a result of discussions.

1) Dawtacha Intake Dam (DTC)

a) Water Level Gauge (Spillway)

EPGE will prefer to utilize a staff gauge, which has been installed after the trouble of water level gauge, for the monitoring of water level.

b) Rain Gauge

EPGE will abandon to observe rainfall data at Dawtacha.

c) Communication System (DTC-LKW)

EPGE will prefer to utilize mobile phone for the communication between Dawtacha and Loikaw city gauging station.

d) Emergency Diesel Generator

EPGE will transfer existing EDG (150 kVA), which will be replaced to new one (refer to



Chapter 7), from the powerhouse to Dawtacha.

2) Regulation Pondage (PDG)

a) Water Level Gauge (Upstream #2)

EPGE will be enough to utilize only one (1) water level gauge (upstream #1) for the monitoring of water level.

b) Fence around the Pondage

EPGE will repair damaged fence by their budget.

c) Communication System (PDG-BHP1)

Observed data of water level gauge (upstream #1) will be recorded by EPGE staff at the valve house instead of automatic data transmission.

3) Powerhouse (BHP1)

a) Water Level Gauge (Tailrace)

EPGE will use up existing one until its lifetime.

b) Steel Rolling Door

EPGE will use up existing one until its lifetime.

4) Loikaw City Gauging Station (LKW)

a) Rain Gauge

EPGE will receive rainfall data which is observed by other authority/organization in Loikaw city.

9.3.2 Sedawgyi HPP

(1) Item for Basic Design

According to the screening result of "A" and "B" listed in Table 9.2-2, EPGE and JICA Survey Team had a series of discussions from May to September 2016 regarding the target facilities/equipment of Sedawgyi HPP to be rehabilitated.

Finally EPGE and JICA Survey Team decided and agreed the rehabilitation item of civil facilities for Sedawgyi HPP as shown in Table 9.3-2.



Table 9.3-2 Agreed Civil Facilities at Sedawgyi HPP for the Rehabilitation Project Hydropower Plant Sedawgyi *1 Screening for the

Rehabilitation Project A :Required B :Recommended C :Not Required




Sc

ree

nin

g*1

Me

as

ure

s*2

Urg

en

cy*3

(1) Concrete DamDam body C

Breast wall A P I ID's contermeasure is necessary.Stoplog groove CGate groove B P I Site inspection shall be conducted in 2017.Breast wall CStoplog groove CGate groove B P I Site inspection shall be conducted in 2017.

Overflow SectionNon Overflow Section CDam Crest C

Observation instruments B R III ID's matterDrainage pump B R III ditto

(2) Earthfill DamUpstream Slope B P III ID's matterDownstream Slope B P II dittoDam Crest C

(3) Rockfill DamUpstream Slope B P III ID's matterDownstream Slope CDam Crest C

(4) SpillwayInlet CSpillway Crest CChute CEnergy Dissipator (Apron) C

(5) Penstock C(6) Powerhouse

Building CTailrace COthers Reservoir A A II Yes, additionally install To be additionally installed

Tailrace A A II Yes, additionally install To be additionally installed(7) Left Saddle Dam

Upstream Slope CDownstream Slope CDam Crest B P III ID's matter

(8) Right Saddle DamUpstream Slope B P III ID's matterDownstream Slope CDam Crest B P III ID's matter

(9) ReservoirWatershed CSedimentation C

InspectionGallery

Water levelgauge

ID's matter(rehabilitation work for gate No.1)

Final Decision

Screening Result

PowerDamSection



ComponentsEPGE

Approval



(2) Water Level Gauge

According to Table 9.3-2, two (2) water level gauges as shown below are agreed for additional installation.

1) Powerhouse

a) Reservoir



Observation Point: Control Room (Cable Length: 350 to 400 m)


b) Tailrace



Observation Point: Control Room (Cable Length: 250 to 300 m)


(3) Deselected Item

According to Table 9.3-2, below item, which are under the jurisdiction of ID, are deselected from the rehabilitation item as a result of discussions with EPGE. In addition, JICA Study Team had an opportunity to discuss with ID regarding this issue particularly for maintenance gate, penstock gate and spillway gate only.

1) Concrete Dam

a) Breast Wall at the Intake Tower for Unit 1 (Part of Maintenance Gate)

ID planned to rehabilitate in June 2016, however, they could not conduct rehabilitation works because of high water level of reservoir (refer to 1), (1) of Section 9.1.2).

b) Gate Grooves at the Intake Tower for Unit 1 and Unit 2 (Part of Penstock Gate)

Necessity of rehabilitation will be studied through site investigation by the Consultants during preliminary design stage of the Project.

c) Observation Instruments at the Inspection Gallery

d) Drainage Pump at the Inspection Gallery

2) Earthfill Dam

a) Upstream Slope

b) Downstream Slope



3) Rockfill Dam

a) Upstream Slope

4) Spillway

a) Spillway Gate No.1

ID will conduct repair works after rainy season in 2016 (refer to (4) of Section 9.1.2).

5) Left Saddle Dam

a) Dam Crest

6) Right Saddle Dam

a) Upstream Slope

b) Dam Crest

Chapter 10 Final Report Rehabilitation of Communication Facilities


CHAPTER 10

REHABILITATION OF COMMUNICATION FACILITIES



Chapter 10 Rehabilitation of Communication Facilities As there are some facilities such as Mobye, Dawtacha and Baluchaung No.1 HPP (Hydropower Plant) connected by communication system, rehabilitation plan for communication facilities is prepared in this chapter.

Method, Result of Site Reconnaissance and Issues

As a result of inspection in the filed in Baluchaung HPP (Hydropower Plant), both radio (analogue voice communication on VHF (Very High Frequency) band) and wired (PLC: Power Line Communication) are out of service, except for one hop between Dawtacha and Baluchaung No.1 HPP, because of equipment damage caused by aging and lightning strike (refer to the following figure).

Fig. 10.1-1 Current Situation of Communication System surrounding Baluchaung No.1 HPP

Identification of Rehabilitation of Communication System

For all equipment delivered in 1988, vendor support period has been expired, it is impossible to replace with spare parts.

Basic Design of Communication System

Since system design is determined as reasonable for radio, refreshment of equipment with the same system parameters (e.g. transmission power, frequency) is recommended. The following hardware are recommended to be refreshed (replaced) strongly;

Radio transceiver (4 sets in total) Yagi Antenna (4 sets in total) Feeder lines (4 sets in total) Arrester (4 sets in total)

Wired (PLC) communication part was excluded from rehabilitation target this time, since any equipment with the same specification are not procurable from the market.

Chapter 10 Rehabilitation of Communication Facilities Final Report


(1) Radio System Configuration

Radio Link System in Baluchaung No.1 Hydropower Plant is described as following;

Fig. 10.3-1 Radio Link System surrounding Baluchaung No. 1 HPP

Fig. 10.3-2 Location of Communication Facilities



(2) Estimate Diagram

Estimate Diagrams of Radio link for 2 hops as bellow. No site is within the line of sight.

Fig. 10.3-3 Estimate Diagram between Mobye and Dawtacha

Fig. 10.3-4 Estimate Diagram between Dawtacha and Baluchaung No.1 HPP

7 01 16

MobyeLatitude 019 46 57 NLongitude 097 05 22 EAzimuth 125.82°Elevation 880 m ASLAntenna CL 10.0 m AGL

Dawta-ChaLatitude 019 38 52 NLongitude 097 17 12 EAzimuth 305.89°Elevation 873 m ASLAntenna CL 10.0 m AGL

Frequency (MHz) = 170.0K = 1.33

%F1 = 60.00

Eleva

tion (

m)

870

880

890

900

910

920

930

940

950

Path length (25.49 km)

0

2

46

810 12 14 16

1820

22

24

7 01 16

Dawta-ChaLatitude 019 38 52 NLongitude 097 17 12 EAzimuth 160.71°Elevation 874 m ASLAntenna CL 10.0, 10.0 m AGL

No.1 HPPLatitude 019 34 09 NLongitude 097 18 56 EAzimuth 340.72°Elevation 797 m ASLAntenna CL 10.0, 10.0 m AGL

Frequency (MHz) = 170.0K = 1.33

%F1 = 60.00

Eleva

tion (

m)

790

800

810

820

830

840

850

860

870

880

Path length (9.19 km)

0 1 2 3 4 5 6 7 8 9



(3) Radio Network Design

Radio Network Design Result for 2 hops are described as following. As the transmission margin is secured more than 10dB for both hop, Radio links are found to be operative. Parameter (e.g. transmission power, frequency) for Radio link is not needed.

Table 10.3-1 Radio Network Design Sheet (between Mobye and Dawtacha)

Unit Value

Distance km 25.5

Frequency MHz 170.0 Transmitter Side (1) Transmitter Power W 10.0

dB 40.0 (2) Antenna Gain dBi 10

(3) Feeder Loss dB 2.6

(4) Loss in Duplexer and Arrester dB 4.5

(5) Equivalent isotropic radiated power dBm 42.9 Receiver side

(6) Antenna Gain dBi 10



(9) Total Gain in Receiver side dB 2.9 Propagation loss

(10) Free space propagation loss dB 105.1

(11) Spherical earth shielding loss dB 8.0

(12) Total Propagation loss dB 113.1 Evaluation (13) Total Receive Power dBm -67.3

(14) Total Noise dBm -115.2

(15) Required S/N dB 33.3

(16) Required Receive Power dBm -81.9

(17) Transmission Margin dB 14.6



Table 10.3-2 Radio Network Design Sheet (between Dawtacha and Baluchaung No.1 HPP)

Unit Value

Distance km 9.2

Frequency MHz 170.0

Transmitter Side (1) Transmitter Power

W 10.0 dB 40.0




(5) Equivalent isotropic radiated power dBm 42.9

Receiver side




(9) Total Gain in Receiver side dB 2.9

Propagation loss

(10) Free space propagation loss dB 96.3

(11) Spherical earth shielding loss dB 6.0

(12) Total Propagation loss dB 102.3

Evaluation (13) Total Receive Power dBm -66.5

(14) Total Noise dBm -115.2

(15) Required S/N dB 33.3

(16) Required Receive Power dBm -81.9

(17) Transmission Margin dB 25.4

<Calculation Formula>

(5) = (1) + (2) – (3) – (4) (9) = (6) – (7) – (8) (12) = (10) + (11) (13) = (5) + (9) – (12) (16) = (14) + (15) (17) = (13) – (16)



Verification of Radio Link Design by Field Measurement


(1) Purpose of Measurement

To check the validity of Radio link design for the link between Mobye and Dawtacha (slant distance 25.52 km), field measurement test was executed in Pekon village, where is the way point between Mobye and Dawtacha. Checking the validation between the simulated receiving level and the measured receiving level, reliability of Radio link design is confirmed.

(2) System Configuration for Measurement

The following equipment’s were used for field measurement. Because of short leading time, measurement equipment (e.g. Spectrum Analyzer) was not ready to use, that’s why the commercial shore digital television tuner and SDR (Software Definition Radio) were used for measurement this time.

Table 10.4-1 Measurement Equipment for Field Survey

Part Item Description Purpose

Antenna Yagi Antenna (3 elements, 140 ~ 160MHz)

Gain 4dBi. To be able to use for 170MHz with lower gain.

Feeder COAX cable (10m)

Receiver DS-DT305BK USB type shore digital television tuner

USB extension cable (1.5m) was used to avoid interference from Note PC

Measurement Equipment HDSDR

HDSDR (one of the Software Definition Radio) installed on Note PC

After decoding narrow band FM, voice quality and receiving level were monitored

For the measurement, Note PC on which SDR software is installed and USB type receiver were installed in the vehicle, Yagi antenna connected via COAX cable was installed out of vehicle at 3m height. After setting antenna azimuth to the direction of transmission site (Dawtacha), narrow band FM signal was sent from Dawtacha. After decoding signal using SDR, voice quality and receiving level were monitored. Because of radio license limitation, no signal was sent from measurement vehicle side. This measurement was performed in 16 points in total. Measurement system configuration was described in the following figure;



Fig. 10.4-1 Configuration of Field Survey

Photo 10.4-1 Measurement Point 6

Photo 10.4-2 Measurement Point 8 Photo 10.4-3 Measurement Point 2



(3) Field Measurement Result

Measured receiving level and calculated receiving level (simulated by Mobile Radio) are summarized in the following table. Measured receiving level is higher than calculated receiving level (“delta” in the table, 16dB in average), this is simply because calibration of measurement system was not executed at this time. Measured data where delta is higher than 21dB or lower than 11dB is need to be focused. Since all points whose delta is higher than 21dB (Point 1, 4, 10, 11, 12 and 16) were located in the rice field without any obstacle, reflected wave from rice field might be the contributor of high receiving level. On the other hand, since all points whose delta is lower than 11dB (Point 7, 8 and 14) were located in the densely-populated place with high trees, loss by those tree or houses might be the obstacle of radio signal.

Table 10.4-2 Comparison between Field Survey Record and Simulated Value by Software

Point Name

Slant distance from

Dawtacha [km]

Longitude Latitude Altitude [m] Voice Quality

Measured RSSI [dBm]

Simulated RSSI [dBm]

delta

0 9.74 19°40′44.21″ 97°11′10.57″ 883.7 Good -96.1 -111.7 15.6

1 11.72 19°41′15.70″ 97°10′59.14″ 876.2 Good -99.3 -120.7 21.4

2 12.53 19°41′42.99″ 97°10′41.40″ 876.7 Good -103.6 -121.0 17.4

3 13.44 19°42′06.83″ 97°10′18.86″ 875.8 Good -103.6 -122.4 18.8

4 14.37 19°42′31.09″ 97°09′56.14″ 878.1 Good -102.6 -124.3 21.7

5 15.32 19°42′54.44″ 97°09′32.57″ 876.0 Good -110.4 -125.2 14.8

6 16.28 19°43′18.56″ 97°09′09.28″ 875.9 Good -112.0 -122.3 10.3

7 17.20 19°43′31.29″ 97°08′38.33″ 878.9 Very poor -117.2 -122.2 5.0

8 18.13 19°43′50.47″ 97°08′15.54″ 877.7 Cannot hear -117.3 -121.7 4.4

9 18.96 19°44′07.38″ 97°07′53.04″ 879.1 Good -103.2 -120.6 17.4

10 20.08 19°44′33.29″ 97°07′24.59″ 877.3 Poor -102.9 -123.6 20.7

11 20.85 19°44′52.05″ 97°07′05.81″ 879.5 Good -102.2 -123.5 21.3

12 22.37 19°44′37.81″ 97°05′56.39″ 875.6 Good -107.5 -127.7 20.2

14 24.13 19°45′10.72″ 97°05′06.59″ 913.5 Good -104.9 -112.0 7.1

16 25.79 19°46′13.56″ 97°04′39.63″ 936.2 Very poor -107.8 -130.8 23.0

Mobye 25.52 19°46′55.19″ 97°05′22.16″ 887.3 Poor -107.4 -124.3 16.9

Average 16.0

In the following graph, the above result is shown as plot graph. X axle is the slant distance from Dawtacha, and X axle is the receiving level. Blue points represent measured value, and orange points represent simulated level. Dot lines are linear approximated curve both for measurement value and simulated value. In the following figure, measured level is plotted on the map.



Fig. 10.4-2 Simulated RSSI and Measured RSSI

Fig. 10.4-3 Track Record of Field Survey

-135.0

-130.0

-125.0

-120.0

-115.0

-110.0

-105.0

-100.0

-95.0

-90.00.00 5.00 10.00 15.00 20.00 25.00 30.00

Simulated RSSI and Measured RSSI

MeasuredRSSI[dBm]

SimulatedRSSI[dBm]

線形 (Measured RSSI[dBm])

線形 (Simulated RSSI[dBm])



(4) Conclusion

Though the actual measured level varies from simulated level, since clutter data (e.g. bare ground, forest, rice field, etc.) is not considered in the simulation using Mobile Radio, the simulated value is acceptable. Especially in Mobye where the Radio Station is located, delta between the simulated level and the measured level is 16.5dB, which is almost the same as the average validation (16dB). It can be concluded that Radio link design result using simple simulator is reliable. Additionally, in the commercial system, antenna height is higher that this time (3m 15m), and antenna gain is much higher than this time (4dBi→8dBi), the actual receiving level in Mobye is expected to be 5dB higher than measured value. As conclusion, radio parameter update (transmission power, frequency, bandwidth, etc.) is not needed after hardware rehabilitation.

Recommended Specification

(1) Radio Equipment

The recommended specification of radio equipment after rehabilitation is summarized as following table. In term of radio specifying, specification after rehabilitation is almost equal as that before rehabilitation. In term of environmental specification, much higher (stronger) waterproof/dustproof specification is required, specifically IP54 level at least.

Table 10.5-1 Specification for Communication Facilities Transmitter Receiver Remark

Physical Specification Dimensions less than 50x180x150mm HxWxL Weight less than 2kg Environmental Specification Operating Temperature -10°C / +60°C Storage Temperature -10°C / +80°C Thermal Shock US MIL-STD-810G Humidity US MIL-STD-810G Dust and Water proof IP54 or US MIL-STD-810G Radio Specification Frequency 165-175MHz Secured for fixed radio in

Myanmar Channel Spacing 12.5kHz Frequency Stability ±0.5ppm -30°C, +60°C, +25°C

(Reference) Transmission Power 10W N/A Receiving Sensitivity N/A -117dBm (Analogue)

-119dBm(Digital)

S/N Ratio N/A -40dB FM, 12.5kHz Conducted Spurious Emission -57dBm -36dBm < 1GHz

-30dBm < 1GHz

Spurious Rejection N/A 75dB Modulation Scheme Analogue Modulation Narrowband FM Digital Modulation 4FSK Digital Protocol ETSI TS 102 361-1,-2,-3

(2) Antenna

Yagi antenna with 5 or 8 elements (vertical polarization, more than 8dBi gain) is recommended.

Chapter 11 Power System Analysis Final Report for required Expansion of Transmission Line


CHAPTER 11

POWER SYSTEM ANALYSIS FOR REQUIRED EXPANSION OF TRANSMISSION LINE



Chapter 11 Power System Analysis for required Expansion of Transmission Line

Existing System and the Issues

11.1.1 Outline

On the relevant transmission line and substation facilities which are not installed in the target power stations in the project, necessity for their expansion will be checked to the system reliability in order to apply Japanese ODA (Official Development Assistance).

The scope of relevant transmission line and substation facilities is shown in Fig. 11.1-1.

Baluchaung No.1 HPP (Hydropower Plant) • Baluchaung No.1 HPP ~ Baluchaung No.2 HPP (132kV) • Baluchaung No.2 HPP ~ Taungoo S/S (substation) (230kV)

Sedawgyi HPP • Sedawgyi HPP ~ Belin S/S (132kV)

The viability of power transmission generated by the target existing power stations will be confirmed by of power system analysis. In the analysis, power flow, power system stability, transmission loss is to be simulated and checked in order to check the power transmission stability in the case of transmission line faults. The simulation tool is PSS/E* which is used all over the world.

* PSS/E: Power Transmission System Planning Software

Difficulty of the power transmission generated by the existing facilities is identified, the optimal power system expansion scenario will be proposed out of the alternative expansion scenarios from the viewpoint of reliability, economy and environment.


In the existing system as of 2016 year, generation power of Baluchaung No.1 HPP is transmitted to Baluchaung No.2 HPP, where two routes of 230kV T/L (transmission line) and one route of 132kV T/L are connected. One route of 230 kV T/L is for Taungoo S/S, and the other route is for Shwemyo S/S, which will start operation soon. The route of 132kV T/L is for Tigyit TPP (Thermal Power Plant) via Loikaw S/S. The existing power system is shown in Fig. 11.1-2. As the rated capacity of Baluchaung No.1, No.2 and No.3 HPPs, and the transmission capacity of T/L are shown in Fig. 11.1-2, the capacity of 230kV T/L for Taungoo is 211MW, whose capacity is usually less than total capacity of 248MW of Baluchaung HPPs. Therefore, 132kV bus of Baluchaung No.2 HPP is usually separated in operation, and the generation power of Baluchaung No.2 HPP is transmitted by 230kV T/L and the generation power of Baluchaung No.1 and No.3 HPPs is transmitted by 132 kV T/L.

As of 2020 year as shown in Fig. 11.1-3, Tigyit TPP is planned to be rehabilitated and the generation power will be increased to 120MW. As the result, the generation power of Baluchaung No.1 and No.3 HPPs cannot be transmitted by 132kV T/L and the generation power must be transmitted by two routes of 230kV T/L. But when the 230kV T/L for Shwemyo is tripped by fault, the rested 230kV T/L for Taungoo will be overloaded. Therefore one more route of 230kV is necessary for transmitting Baluchaung No.1, No.2, and No.3 HPPs. On the other hand, when the 132kV T/L between Tigyit TPP and Kalaw S/S is tripped by fault, over load of T/L will not happen.

Chapter 11 Power System Analysis for required Expansion of Transmission Line Final Report


Fig

. 11.

1-1

Sco

pe o

f rel

evan

t Tra

nsm

issi

on L

ine

and

Subs

tatio

n F

acili

ties

Seda

wgy

i

Balu

chau

ngN

o.1



Fig. 11.1-2 Power System surrounding Baluchaung HPPs (as of Year 2015)

In conclusion, one more route of 230kV is necessary for transmitting Baluchaung No.1, No.2, and No.3 HPPs as of 2020 year.

Fig. 11.1-3 Power System surrounding Baluchaung HPPs (as of Year 2020)

Shwemyo S/S

Taungoo S/S

230kV132kV

BLC. No.114MW×2

S S BLC. No.326MW×2

Tykyit P/S

Loikaw S/S

×

66kVOperation

BJC. No.2 P/S

BLC Total Power Generation 248MW

S

161MW

10MW

108MW

80MW

0MW

5MW

65MW(Capacity:211MW/cct)

2MW 3MW

60MW

BLC. No.228MW×6

S

7MW

(Capacity:358MW/cct)

75MW

(Capacity：79MW/1cct)

(Operation Start2016,soon)

Shwemyo S/S

Taungoo S/S

230kV132kV

BLC. No.228MW×6

S

BLC. No.114MW×2

S S BLC. No.326MW×2

Tykyit P/S

Loikaw S/S

×

66kVOperation

Kalaw S/S

BJC. No.2 P/S

BLC Total Power Generation 248MW

S

243MW

20MW

163MW(usual)

80MW

120MW

5MW

29MW(Capacity:211MW/cct×1.1=232MW)

2MW9MW

3MW

86MW (usual)

①

/ 243MW(fault①)

②

/86MW (fault②)

(Capacity:79MW/cct×1.1=87MW)(Capacity:

358MW/cct×1.1=394MW)




Sedawgyi HPP is connected by two 132kV T/L, one T/L is for Belin S/S which is located at Mandalay area via Aungpinale S/S and Tagundine S/S, and the other T/L is for Letpanhla S/S which is located at the northern area (refer to Annex 11). Based on results of power system analysis (refer to Section 11.3.3), the generation power of Sedawgyi HPP can be transmitted by the existing power system.

In conclusion, the expansion of power system surrounding Sedawgyi HPP is not necessary.

On the other hand, there was EPGE (Electric Power Generation Enterprise) request for the short circuit current study and necessity study of shunt reactor of Sedawgyi HPP. Therefore, the power system analysis is carried out. As the result, the short circuit current is under general short capacity of circuit breaker, and the shunt reactor is not necessary for Sedawgyi HPP. (refer to Annex 11)



Power System Expansion Scenario

11.2.1 Preparation of the Power System Expansion Scenario around Baluchaung No.1 Hydropower Plant

Based on the issue of existing power system surrounding Baluchaung HPPs, five scenarios are settled. The name of each scenario is Scenario A, B, C, C’ and C”.

On Scenarios A and B, one more route of 230 kV T/L is expanded between Baluchaung No.2 HPP and neighboring 230 kV substations.

On Scenario C, in the case of difficulty of one more route of 230 kV T/L, by supplying Baluchaung HPPs generation power to the near upgraded substation, the generation power can be transmitted by existing T/Ls. Scenario C’ and C” are the optional scenarios of Scenario C considering economic viewpoints.

Scenario A: Expansion of 230kV T/L 1cct 159km Baluchaung 2 HPP - Taungoo S/S Scenario B: Expansion of 230kV T/L 1cct 193.1km Baluchaung 2 HPP - Shwemyo S/S Scenario C: Expansion of 230kV T/L 1cct 20km Baluchaung 2 HPP - Loikaw S/S Scenario C’: Expansion of 132kV T/L 1cct 15km Baluchaung 1 HPP - Loikaw S/S Scenario C”: Expansion of 33kV D/L* 1cct 20km Baluchaung 2 HPP - Loikaw S/S

*D/L : Distribution Line

Each scenario and the evaluation are precisely described in Annex 11.

For Scenario C-C”, these are studied as an alternative plan in case of the difficulty of Scenario A and B implementation.

In conclusion, these scenarios are desirable to be considered for the future countermeasure.



Power System Analysis

11.3.1 Outline

The feasibility of power transmission generated by the target power plants, Baluchaung No.1 HPP and Sedawgyi HPP, are confirmed by means of power system analysis. Power flow analysis, power system stability analysis and transmission loss analysis, are carried out. Power flow of each T/L and voltage of each substation or power plants is to be simulated and checked for the power system surrounding Baluchaung No.1 HPP and Sedawgyi HPP by the power flow analysis. Transient stability is simulated and checked in the case of the T/L faults to Baluchaung No.1 HPP and Sedawgyi HPP by power system stability analysis. Comparison of transmission loss among expansion scenarios of power system surrounding Baluchaung HPPs are also carried out in transmission loss analysis.

Power system analysis is based on the data obtained from PSD (Power System Department) and future system data until 2020 year is obtained from Department of Power Transmission Project (PTP). The analysis is carried out as of 2020 year. Substation load as of 2020 is based on Myanmar’s master plan data by MOEE (Ministry of Electricity and Energy) and JICA (Japan International Cooperation Agency) (2015). The power system analysis tool is PSS/E which is used all over the world.


(1) Power flow analysis result

For existing system surrounding Baluchaung HPPs, power flow analysis is shown in Fig. 11.3-1. 230kV T/L between Baluchaung No.2 P/S and Taungoo S/S is the bottleneck T/L in the case of the 230kV T/L fault between Baluchaung No.2 and Shwemyo S/S as mentioned in Section 11.1.2.

For expansion scenarios of power system surrounding Baluchaung HPPs, power flow analysis is carried out and there are no bottleneck T/L and no over or under voltage bus (±5%). (refer to Annex 11)

In conclusion, there is no issue for each expansion scenario on the viewpoint of power flow analysis.

(2) Power stability analysis result

For expansion scenarios of the power system surrounding Baluchaung HPPs, transient stability is simulated and checked by causing the three phase short fault at the nearest T/L for 0.1 second period (5 cycles) and opening the T/L. The time chart of the generator angle of Baluchaung No.1 HPP and the bus voltage of Baluchaung No.2 HPP are referred to Annex 11. As the result, the power system surrounding Baluchaung HPPs of each expansion scenario is estimated to be stable on the viewpoint of power system stability.



Fig. 11.3-1 Power Flow in Existing System as of 2020


(1) Power flow analysis result

For the existing power system surrounding Sedawgyi HPP, power flow analysis is carried out as shown Fig. 11.3-1. There is no bottleneck T/L and no over or under voltage bus (±5%).

In conclusion, there is no issue for the existing power system surrounding Sedawgyi HPP on the viewpoint of power flow analysis.

Sedawgyi P/S

Baluchaung P/S



(2) Power stability analysis result

For the existing power system surrounding Sedawgyi HPP, transient stability is simulated and checked by causing the three phase short fault at the nearest 132kV T/L for 0.1 second period (5 cycles) and opening the T/L. The time chart of the generator angle of Sedawgyi HPP and the bus voltage of Aungpinale S/S and Sedawgyi HPP are referred to Annex 11. As the result, the existing power system surrounding Sedawgyi HPP is estimated to be stable on the viewpoint of power system stability.



Conclusion and Recommendations

11.4.1 Conclusion

Conclusions of Power system analysis results are as follows;

• JICA Survey Team prepared power system expansion scenarios surrounding Baluchaung HPPs, which are studied based on power system analysis, economy and the feasibility. The scenarios are desirable to be considered for the future countermeasure.

• Concerning to the surrounding power system of Sedawgyi HPP, there is no issue to transmit the generation power by existing power system based on the power system analysis.



Site Reconnaissance of Relevant Substation and Transmission Line Facilities outside Power Plants

11.5.1 Substation in the Baluchaung No.2 Hydropower Plant

(1) Site location

Baluchaung No.2 HPP is located about 20km southeast far from the Loikaw city the capital of the Kayah State, and surrounded by mountains. Access road is paved with asphalt and part of this road around the Lawpita is passing a mountain area. But, its accessibility from the Loikaw city is generally fine.

In addition, Baluchaung No.2 HPP has a 230/132/33/11kV substation which is located beside the HPP.

Source: Prepared by JICA Survey Team based on Google Earth

Fig. 11.5-1 Site Location of the Baluchaung HPPs and Loikaw S/S

(2) Substation facilities

The general configuration of substation facilities in the Baluchaung No.2 HPP are shown as follows;

T/L bay 230kV (Under operation) : 1 bay (Taungoo line) 230kV (To be operated) : 1 bay (Shwemyo line) 230kV (Spare) : 4 bays 132kV (Under operation) : 4 bays (N/L × 2, BAL No.1 line and BAL No.3 line)

Busbar Configuration 230kV : Single bus 132kV : Double bus



Transformers Main transformer : 132/11kV 10.3MW × 3 units × 6 banks Booster transformer : 230/132kV 33.333MW × 3 units × 4 banks

(3) System configuration

Existing single line diagram of the Baluchaung No.2 HPP as of Jan. 2016 is shown as Fig. 11.5-2. Usually, 132/11kV main transformers of unit No.1 and No.2 are connected to 132kV bus-C and supplying its electricity to 33kV and 11kV local D/L through 132/33/11kV inter-bus transformer. On the other hand, units No.3 to No.6 are connected to 132kV bus-B and supplying its electricity to 230kV grid through the 132/230kV booster transformers and 230kV Taungoo T/L. The Baluchaung No.2 HPP keeps this bus operation method usually. However, all main transformers would be connected to 132kV bus-A in order to respond the demand situation.

EPGE has a plan to relocate T/L bays of northern line 1, northern line 2 and the Baluchaung No.1 HPP line. These three T/Ls will be shifted to existing T/L bay of the Baluchaung No.3 HPP side for securing the space to install switchgears on primary side of booster transformer for the Shwemyo line. Single line diagram of after relocation work is shown as Fig. 11.5-3.

Source: EPGE

Fig. 11.5-2 Existing Single Line Diagram of the Baluchaung No.2 HPP as of Jan. 2016



Source: EPGE

Fig. 11.5-3 Single Line Diagram of the Baluchaung No.2 HPP after Relocation Work

(4) Substation layout

The substation of the Baluchaung No.2 HPP is composed of fifteen 132kV bays and five 230kV bays. Existing S/S layout is shown as Fig. 11.5-4. The following six bays are occupied as T/L bay. And, there are four spare 230kV T/L bays in red hatching in Fig. 11.5-4.

: 132kV Baluchaung No.3 HPP line : 132kV Baluchaung No.1 HPP line : 132kV Northern line 1 : 132kV Northern line 2 : 230kV Taungoo line : 230kV Shwemyo line

230kV to Shwemyo line is currently under construction and will start its operation in 2016. As shown in single line diagram of Fig. 11.5-2 and Fig. 11.5-3, 230kV bus bar between the Taungoo line and Shwemyo line is not connected due to a discrepancy of transformer impedance of each booster transformers.

As described in the sub-section (3), EPGE has a plan to relocate 132kV T/L bays for the Baluchaung No.1 HPP line, northern line 1 and northern line 2 which are shown as Fig. 11.5-5. This relocation work will be done in order to secure the space for installation of switchgears on primary side of booster transformer for the Shwemyo line.



Source: Prepared by JICA Survey Team

Fig. 11.5-4 Existing Substation Layout of the Baluchaung No.2 HPP as of Jan, 2016


Fig. 11.5-5 Substation Layout of the Baluchaung No.2 HPP (After relocation work)

(5) Protection scheme of 132kV T/L to Baluchaung No.1 HPP

Distance relays are equipped to existing protection panel as main protection and also back-up protection. This protection scheme is same as existing protection panel in the Baluchaung No.1 HPP.

(6) Feasibility of T/L extension

As described in the previous section, there are four spare 230kV T/L bays in the S/S. Hence, it is possible to install switchgear for new 230kV T/L. However, a land which is for construction of new 230kV T/L is limited because of this S/S is located in bottom of valley and surrounded by

* To be used for switchgears of primary side on the booster transformer.



Baluchaung River, shallow stream and existing facilities. Therefore, further study is necessary for an arrangement of T/L facilities.


Fig. 11.5-6 Surrounding Situation of the Baluchaung No.2 HPP

132kV transmission line to Baluchaung No.3 HPP Baluchaung River

Shallow stream Source: Prepared by JICA Survey Team

Photo 11.5-1 Site Survey around the Baluchaung No.2 HPP

132kV Baluchaung No.3 HPP line

Baluchaung River

Shallow stream




(1) Site Location

As shown in Fig. 11.5-1, the Baluchaung No.1 HPP is located about 15km southeast far from the Loikaw city, the capital of the Kayah State. Most of access road is paved with asphalt. Only a road between the Baluchaung No.1 HPP and nearest main road is unpaved. But, its accessibility from the Loikaw city is generally fine. In addition, the Baluchaung No.1 HPP has a 132/11kV S/S which is located beside the HPP.

(2) S/S facilities

The general configuration of S/S facilities in the Baluchaung No.1 HPP are shown as follows;

T/L bay 132kV (Under operation) : 1 bay (BAL No.2 line) Busbar Configuration 132kV : None Transformers Main transformer : 132/11kV 10.333MW × 3 units × 1 bank


Existing single line diagram of the Baluchaung No.1 HPP is shown as Fig. 11.5-7. Units No.1 and No.2 generators are connected to the 132/11kV main transformer through 11kV bus and supplying its electricity to 132kV grid and 11kV local D/L. And, there is no 132kV bus in the S/S so that the main transformer is connected to the 132kV grid directly.

Source: EPGE

Fig. 11.5-7 Single Line Diagram of the Baluchaung No.1 HPP



(4) Substation layout

The S/S of the Baluchaung No.1 HPP is composed of one 132kV bay for the Baluchaung No.2 HPP line. Hence, there is no 132kV bus in the S/S so that there is no spare 132kV T/L bay. Existing S/S layout is shown as Fig. 11.5-8.


Fig. 11.5-8 Substation Layout of the Baluchaung No.1 HPP

(5) Feasibility of transmission line extension

As described in the previous section, there is no spare 132kV T/L bay in the S/S. In case of extend a T/L, 132kV bus and switchgear for T/L bay including additional line shall be added in the S/S. Although, there is a space to extend the S/S to a guard house side. There is not enough space to extend the S/S to powerhouse side. Furthermore, drastic arrangement change is required for installation of additional S/S facilities. Therefore, it is not recommended to extend new 132kV T/L.




Fig. 11.5-9 Surrounding Situation of the Baluchaung No.1 HPP

Unused space Guard house

Premises road in front of power house Source: Prepared by JICA Survey Team

Photo 11.5-2 Site Survey around the Baluchaung No.1 HPP

Permission roadE

Guard house

Unused space



11.5.3 Loikaw S/S

(1) Site location

As shown in Fig. 11.5-1, the Loikaw S/S is located about 5km southeast far from the Loikaw city, the capital of the Kayah State. Access road is paved with asphalt. Its accessibility from the Loikaw city is fine.

(2) Substation facilities

The general configuration of S/S facilities in the Loikaw S/S are shown as follows;

T/L bay 132kV (Under operation) : 4 bay (Baluchaung No.2 HPP line × 2, Tigyit TPP line × 2) Busbar Configuration 132V : Double bus Transformers Main transformer : 132/33/11kV 50MVA × 1 bank


Existing single line diagram of the Loikaw S/S is shown as Fig. 11.5-10. There is one 132/33/11kV main transformer (50MVA) in the S/S. This main transformer is connected to 33kV bus and 11kV bus and supplying its electricity to 33kV and 11kV local D/L.

Source: PTSCD

Fig. 11.5-10 Single Line Diagram of the Loikaw S/S



(4) S/S layout

The Loikaw S/S is composed of eight 132kV bays. Existing S/S layout is shown as Fig. 11.5-11. 132kV switchyard is consisted of four T/L bays and three switching bays and one spare bay as follows.

: 132kV Baluchaung No.2 HPP line 1 : 132kV Baluchaung No.2 HPP line 2 : 132kV Tigyit TPP line 1 : 132kV Tigyit TPP line 2 : Switching bay to connect 132/33kV transformer : Spare : Switching bay to connect PT of bus (B) : Switching bay to connect PT of bus (A) and bus coupler


Fig. 11.5-11 S/S Layout of the Loikaw S/S

Available space




As described in the previous section, there is one spare 132kV T/L bay in the S/S. However, the spare bay seems to be used for switching bay of the 132/66kV transformer because of 132/66kV transformer is located on the same line with the spare bay as Fig. 11.5-11. In case of the spare bay will be used for 132/66kV transformer, extension of 132kV bus will be required for extension of new 132kV T/L. There is an available space in opposite from control building side. Therefore, it is assumed to be able to extend 132kV bus and new 132kV T/L.

In case of extension of 230kV T/L, space for construction of following six 230kV bays and 230/132kV transformer will be required. 230kV switchyard will be able to be constructed at the available space in opposite from control building side. Furthermore, there are no obstacles around the S/S so that even land extension seems to be possible. Therefore, it is assumed to be able to extend new 230kV T/L.

: 230kV incoming Baluchaung No.2 HPP – Taungoo line bay : 230kV outgoing Baluchaung No.2 HPP – Taungoo line bay : 230kV incoming Baluchaung No.2 HPP – Shwemyo line bay : 230kV outgoing Baluchaung No.2 HPP – Shwemyo line bay : 230kV in coming Baluchaung No.2 HPP – Loikaw S/S bay : 230kV switching bay for 230/132kV transformer

Source: PTSCD

Fig. 11.5-12 Surrounding Situation of the Loikaw Substation



11.5.4 Shwemyo S/S

(1) Site location

The Shwemyo S/S is located about 35km northeast far from the Naypyidaw city, the capital of Myanmar. Access road is paved with asphalt. Its accessibility from the Naypyidaw city is fine.


Fig. 11.5-13 Site Location of the Shwemyo S/S

(2) S/S facilities

The general configuration of S/S facilities in the Shwemyo S/S are shown as follows;

T/L bay 230kV (Under operation) : 3 bay (Thazi line, Pyinmana line and Naypyidaw 2 line) 230kV (To be operated) : 1 bay (Baluchaung No.2 HPP line)

Busbar Configuration 230kV : Single bus

Transformers Main transformer : 230/33/11kV 33.33MVA × 3 units × 1 bank

Phase modifier Shunt reactor : 230kV 20Mvar × 1unit


Existing single line diagram of the Shwemyo S/S is shown as Fig. 11.5-14. There is one 230/33/11kV main transformer (33.33MVA × 3) in the S/S. Shunt reactor is connected to the 230kV bus as a phase modifier. The 230kV Baluchaung No.2 HPP line is not shown in the single line



diagram, because this T/L is under construction and will start its operation in 2016.

Source: PTSCD

Fig. 11.5-14 Single Line Diagram of the Shwemyo S/S



(4) S/S layout

The Shwemyo S/S is composed of five 230kV bays. Existing S/S layout is shown as Fig. 11.5-15. The 230kV switchyard consist of four T/L bays and one switching bay. There is no spare 230kV T/L bay.

: 230kV Thazi line : 230kV Pyinmana line : 230kV Naypyidaw 2 line : 230kV Baluchaung No.2 HPP line (Under construction) : 230kV Shunt reactor


Fig. 11.5-15 Layout of the Shwemyo S/S

Available space 1

Available space 2

Available space 3




As described in the previous section, there is no spare 230kV transmission line bay in the substation. On the other hand, the S/S has a lot of available spaces as blue hatching in Fig. 11.5-15. In case of extension of T/L, one of these available space will be used for construction of additional T/L bay. If additional 230kV Baluchaung No.2 HPP line will be constructed, the line route would be parallel with existing Baluchaung No.2 HPP line which is currently under construction. It means that an incoming line would be closer to available space 3. Existing 230kV bus can be extended from the switching bay of shunt reactor. Therefore, it is possible to extend 230kV T/L.

Available space 3 Thazi line (Operation) Baluchaung No.2 HPP line

Existing dead-end towers besides the substation Source: Prepared by JICA Survey Team

Photo 11.5-3 Site Survey around the Shwemyo S/S



11.5.5 Taungoo S/S

(1) Site location

The Taungoo S/S is located about 5km south far from the Taungoo city in the Bago Region. Access road is paved with asphalt and its accessibility from the Taungoo city is fine.


Fig. 11.5-16 Site Location of the Taungoo S/S

(2) S/S facilities

The general configuration of S/S facilities in the Taungoo S/S are shown as follows;

T/L bay 230kV (Under operation) : 5 bay (Thephyu line, Baluchaung No.2 HPP line, Tharyargone 1 line, Tharyargone 2 line and Thauk Ye Khat 2 line)

Bus bar Configuration 230kV : Single bus

Transformers Main transformer : 230/33/11kV 20MVA × 3 units × 1 bank


Existing single line diagram of the Taungoo S/S is shown as Fig. 11.5-17. There is one 230/33/11kV main transformer (20MVA × 3) in the S/S. This main transformer is connected to 33kV bus and 33/11kV transformer and supplying its electricity to 33kV and 11kV local D/L.



Source: PTSCD

Fig. 11.5-17 Single Line Diagram of the Taungoo S/S

(4) S/S layout

The Taungoo S/S is composed of six 230kV bays. Existing S/S layout is shown as Fig. 11.5-18. The 230kV switchyard is consisted of five T/L bays and one switching bay as follows. There is no spare 230kV T/L bay.

: 230kV Thephyu line : 230kV Baluchaung No.2 line : 230kV Tharyargone line 1 : 230kV Tharyargone line 2 : 230kV Thauk Ye Khat line 2 : 230kV Switching bay to connect 230/33/11kV transformer




Fig. 11.5-18 Substation Layout of the Taungoo S/S

(5) Feasibility of T/L rehabilitation

PTSCD (Power Transmission and System Control Department) has a construction plan of 500kV new Taungoo substation where is located about 10km northwest far from the Taungoo city. Furthermore, PTSCD has a connection change plan of the existing Baluchaung No.2 HPP - Taungoo T/L and Thephyu - Taungoo T/L shown as Fig. 11.5-19. According to this plan, these 230kV T/Ls will be connected to new 500kV Taungoo S/S. Hence, T/L bay for 230kV T/L between Baluchaung No.2 HPP and Taungoo seems to be secured in the new 500kV Taungoo S/S.




Fig. 11.5-19 Connection Change Plan around Taungoo

Taungoo S/S (Existing) 230kV T/L around Taungoo S/S (Existing)

(to; right: Baluchaung No.2 HPP, left: Thephyu)

Planed construction site of New 500kV Taungoo S/S Prepared by JICA Survey Team

Photo 11.5-4 Site Survey around the Taungoo S/S

To Thephyu S/S

To Baluchaung No.2 HPP

Existing Taungoo S/S

500kV New Taungoo S/S



Transmission Line Route

11.6.1 Transmission Line between Baluchaung No.2 Hydropower Plant - Taungoo S/S

(1) Existing T/L

230kV T/L between Baluchaung No.2 HPP - Taungoo S/S has been 56 years since its commissioning in 1960. Most part of this T/L route is located in mountain side between the Loikaw city and the Taungoo city along with a mountain pass. Outline of this T/L is shown as below;

• 230kV T/L; Baluchaung No.2 HPP - Taungoo S/S Conductor type : ACSR 795MCM Drake Number of bundle : Single bundle Number of circuit : Single circuit Distance : 154.5km Commissioning year : 1960


Fig. 11.6-1 Location of Existing 230kV T/L; Baluchaung No.2 HPP - Taungoo S/S

(2) Fault records

Fault records in 2013 to 2015 are obtained from the Taungoo T/L maintenance office. According to fault records, line faults occurred eighteen times in this three years. Cause of faults are summarized in Table 11.6-1.

Most of causes is not related to deterioration.

(3) Maintenance records

Maintenance records in 2014 to 2016 are obtained from the Taungoo T/L maintenance office.

“Repairing of tower steel materials” and “Repairing of

Table 11.6-1 Fault Records in 2013 to 2015

Cause of fault Times Forest fire smoke 10 Tree contact 5 Lightning stroke 2 Damage to insulators 1

total 18 Source: PTSCD



insulator” seem to be caused by facility deterioration. Furthermore, based on results of interviews with maintenance staffs from PTSCD, there was a component wire broken of ground wire in the past years. The deterioration which corresponds its age have been found.

On the other hand, maintenance staffs from PTSCD can provide several kinds of repairing works such as a replacement of conductor and insulator, replacement of tower steel materials and repairing of stranded wire, etc. Although this T/L has been 56 years, it has not led to fatal accident by a proper maintenance by PTSCD.

(a) Replacement of insulator (b) Tower repairing

Source: PTSCD

Photo 11.6-1 Maintenance Work of T/L

(4) Considerations

It is said that landmines which are located in mountain area have been installed around existing towers to protect towers from insurgents. These landmines are still remaining and surrounded by a fence. However, it is difficult to grasp location of each landmines exactly.

Furthermore, tower collapse caused by the bomb which was installed by insurgents has also been recorded even in recent years shown as Table 11.6-3. Therefore, even if 230kV T/L between Baluchaung No.2 HPP and Taungoo S/S will be rehabilitated, there is a possibility that the line might be bombed again.


As described in previous section, there are considerations of landmine and bomb along with the existing T/L. It seems to be not easy to secure its safety during rehabilitation as well as after rehabilitation. Therefore, it is not recommended to implement rehabilitation in this time.

Table 11.6-3 Summery of List of Collapsed Tower cause of Bombers

Yea Times 1960s 1 1970s 24 1980s 10 1990s 7 2000s 7 2010s 5


Table 11.6-2 Maintenance Record in 2014 to 2016

Kind of maintenance Times

Tree cutting and vegetation maintenance 25

Repairing of tower steel materials 1

Repairing of insulator 1




11.6.2 Balushaung No.2 Hydropower Plant - Shwemyo S/S

(1) Existing T/L

230kV T/L between Baluchaung No.2 HPP and Shwemyo S/S is currently under construction. This T/L is planned to start its operation in 2016. Most part of this T/L route is located in mountain side between the Loikaw city and the Shwemyo S/S along with a mountain pass. Outline of this T/L is shown as below;

• 230kV T/L; Baluchaung No.2 HPP - Shwemyo S/S Conductor type : ACSR 605MCM Duck Number of bundle : Double bundled Number of circuit : Single circuit Distance : 193.1km Operation start year : 2016 (Under construction as of Mar. 2016)


Fig. 11.6-2 Location of Existing 230kV T/L; Baluchaung No.2 HPP - Shwemyo S/S

(2) Fault record

As described previously, this line is currently under construction. Fault records are not available at the present time.

(3) Maintenance record

As described previously, this line is currently under construction. Maintenance records are not available at the present time.

(4) Considerations

Construction work is in progress now. Any considerations on landmine and bombe have not been found.




As described in the previous section, there is no consideration on this T/L route. Therefore, it is assumed to be possible to extend one more 230kV T/L. On the other hand, in case of extend a T/L, it might have an impact on environment and local community due to its long T/L distance. Therefore, further study is necessary for environmental and social consideration survey.

11.6.3 Baluchaung No.2 / No.1 Hydropower Plant - Loikaw S/S

(1) Assumed T/L route

Assumed route for 230kV T/L or 33kV D/L between the Baluchaung No.2 HPP and Loikaw S/S is shown as Fig. 11.6-3. Assumed route for 132kV T/L between the Baluchaung No.1 HPP and the Loikaw S/S is almost same.


Fig. 11.6-3 Assumed Route of Baluchaung No.2 / No.1 HPP - Loikaw S/S Line

(2) Considerations

Any considerations on landmine and bombe have not been found.


As described in the previous section, there is no considerations on the assumed route. Therefore, it is assumed to be possible to extend new T/L or D/L.



11.6.4 Transmission Line around Sedawgyi HPP

(1) 132kV T/L; Sedawgyi HPP - Aungpinlea S/S - Belin S/S

132kV T/L between Sedawgyi HPP and Aungpinlea S/S has been 29 years since its commissioning in 1987. 132kV T/L between Aungpinlea S/S and Belin S/S has been 19 years since its commissioning in 1997 as a 132kV T/L between Sedawgyi HPP and Thazi at first. Then, this T/L has been changed its connection into a current condition in 2009. Most of each T/L route are located in plain area. Outline of each T/Ls are shown as below;

• 132kV T/L; Sedawgyi HPP - Aungpinlea S/S Conductor type : 336.4MCM Number of bundle : Single bundle Number of circuit : Single circuit Distance : 30.2miles Operation start year : 1987

• 132kV T/L Aungpinlea S/S - Belin S/S Conductor type : 336.4MCM Number of bundle : Single bundle Number of circuit : Single circuit Distance : 24.75miles Operation start year : 1997/2009


Fig. 11.6-4 Location of Existing 132kV T/L; Sedawgyi HPP - Aungpinlea S/S - Belin S/S

(2) Fault record

Fault record in 2013 to 2015 could be obtained from the Ohntaw T/L maintenance office. According to these fault records, line faults occurred four times on T/L between Sedawgyi HPP and Aungpinlea S/S and seven times on Aungpinlea S/S - Belin S/S. Cause of faults are summarized in Table 11.6-4 and Table 11.6-5.



Table 11.6-4 Fault Record of T/L; Sedawgyi HPP – Aungpinlea S/S in 2013 to 2015

Table 11.6-5 Fault Record of T/L; Aungpinlea S/S - Belin S/S in 2013 to 2015

Source: PTSCD

Cause of fault Times Hanging chain on conductor 1 Unknown 3


Cause of fault Times Bird nest drop and flash over 3 Broken conductor 1 Unknown 3

total 7

Most of causes seem to be not related to deterioration.

(3) Maintenance record

Maintenance record in 2014 to 2016 are obtained from the Ohntaw T/L maintenance office.

Table 11.6-6 Maintenance Record of T/L; Sedawgyi HPP – Aungpinlea S/S in 2014 to 2016

Kind of maintenance Times Tree cutting and vegetation maintenance 7 Retightening of tower 4 Trimming tree on the right of way 3 Visual inspection of transmission line 2


Table 11.6-7 Maintenance Record of T/L; Aungpinlea S/S - Belin S/S in 2014 to 2016

Kind of maintenance Times Tree cutting and vegetation maintenance 2 Removal of bird nest 6 Repairing of conductor 3 Re-sagging of conductor 1 Visual inspection of transmission line 1


Most of maintenance works seem to be not caused by facility deterioration.

(4) Necessity of rehabilitation

Each transmission lines are not much aged. There is no request for rehabilitation on the viewpoint of deterioration based on interview to maintenance stuff from PTSCD. Therefore, it seems to be not necessary to rehabilitate.

Chapter 12 Final Report Construction Plan and Schedule


CHAPTER 12

CONSTRUCITON PLAN AND SCHEDULE



Chapter 12 Construction Plan and Schedule

Baluchaung No.1 Hydropower Plant

12.1.1 Turbine, Generator and Control Protection System

The disassembly, assembly and installation works at the rehabilitation of Baluchaung No.2 HPP (Hydropower Plant), which has been completed in 2016, were conducted by EPGE (Electric Power Generation Enterprise) under supervisors dispatched from Japanese suppliers. It is judged that they have the high ability for the rehabilitation works under the appropriate supervising. Therefore, it is planed that those works of Baluchaung No.1 and Sedawgyi HPPs are conducted by EPGE under supervision of supervisors of the Contractor.

Tentative number of workers provided by EPGE required for rehabilitation works is given in Table 12.1-1 for Baluchaung No.1 HPP

The rehabilitation works are planned by the following basic policies in consideration of the demand and supply situation of electricity in Myanmar.

(1) One turbine and generator (unit) are possible to be stopped from July to February for 8 months.

(2) The rehabilitation works are implemented one unit by one unit during this period.

(3) The overhead crane must be inspected by a crane manufacture soon after a contract between EPGE and the Contractor. If it is judged by the inspection that any components are necessary to be replaced, the new components must be provided from the crane manufacturer and the replacement work must be finished by EPGE under the supervisor from the manufacturer before the rehabilitation works of turbines and generators.

(4) When the rehabilitation work of turbine inlet valve is conducted, the penstock must be dewatered.

(5) When stoppage of both units is necessary by the rehabilitation works, it is shortened as much as possible.

(6) Necessary measures are conducted at the beginning of the rehabilitation works in order to minimize the influence to the operation unit by stopping the rehabilitated unit.

(7) The changes from existing control and protection system to a new system are conducted before the dry test starts.

(8) The replacement of the generator stator coil is conducted at the present stator setting point by building a scaffolding for disassembly, assembly and installation works.

(9) Because the turbine parts of big dimensions can’t be lifted into the turbine pit through the inside of the stator during stator coil replacement work, the rehabilitation work of the turbine is conducted after stator coil work.

Chapter 12 Construction Plan and Schedule Final Report


Table 12.1-1 Rehabilitation Work Schedule of Baluchaung No.1 HPP (1 unit)

12.1.2 Substation, Transmission Line and Station Service Facilities

It is recommended that the rehabilitation works of S/S (substation), T/L (transmission line) and station service facilities are completed during rehabilitation of preceding unit equipment in both Baluchaung No.1 HPP and Sedawgyi HPP.

(1) During rehabilitation works of the equipment in S/S such as 132 kV GCB (Gas Circuit Breaker), 132 kV busbar and 11 kV cables, etc., the generating power in Baluchaung No.1 HPP will not be able to transmit its electricity to Baluchaung No.2 HPP.

(2) The rehabilitation work of station service equipment such as LV (low voltage) switchgear, AC (Alternating Current) panel, DC (Direct Current) panel and DC battery charger shall be done before changing of control and protection system.

(3) Test and commissioning of T/L protection panel shall be cooperated with Baluchaung No.2 HPP.

(4) Both generators shall be stopped during rehabilitation work of 132 kV switchgear, 132 kV busbar, 11 kV busbar and all 11 kV switchgear. Total period can be estimated about 3 months. Shutdown of both unis shall be scheduled from August to October because power output of Baluchaung No.2 HPP is affected.

The following methods to secure the power to station service load during rehabilitation works are recommended:

Step 1: In order to keep to supply the power to Loikaw city, 11 kV D/L (distribution line) to Loikaw city from Baluchaung No.1 HPP shall be connected to Loikaw S/S by T-brunch on the way to the load.

month -2 -1 1 2 3 4 5 6 7 8【Hydropower Plant】Repair of Overhead craneDisassembling of generator and turbineStator coil disassembly and assemblyRehabilitation/maintenance work on turbineRehabilitationmaintenance work on generatorAssembly of turbineAssembly of generatorDry test of turbine and generatiorReplacement of control system (including GOV & AVR)Chage of control & protection systemsDry test of control systemWet test

【Substaion facilities】WorksTest and Commissioning

【Transmission line facilities】WorksTest and Commissioning

【Station Service facilities】Works

Test and CommissioningScheduled shutdown of 1 UnitScheduled shutdown of 2 Units for Power plant rehabilitationScheduled shutdown of 2 Units for S/S and T/L rehabilitation

Work item

critical path

completion of repair



Step 2: 11 kV feeder to Loikaw S/S in Baluchaung No.1 HPP shall be connected to primary side of 11/0.4 kV station service transformer as shown in the following figure. Then, the station service power can be supplied without going through the 11 kV switchgear.

Step 3: After competed direct connection in Step 2, 11 kV main and local switchgears can be replaced at the same time. Therefore, JICA (Japan International Cooperation Agency) Survey Team recommends to replace 11 kV switchgear at the period of rehabilitation of Unit 1.

Fig. 12.1-1 Temporary Works for Station Service Supply during Rehabilitation Works

of Baluchaung No.1 HPP

Additionally, replacement methods of auxiliary equipment in low tension cubicle room such as LV switchgear, AC panel, DC panel and DC battery charger are recommended as follows:

Step 1: Replacement of existing DC panels and installation of a new AC panel at the position of existing DC panels.

Step 2: Replacement of existing AC panels and installation of a new LV switchgear at the position of existing AC panels.

52H-21200A 10kA

VCB 12kV

250mm21Cx3

60mm21Cx3

3φ 2000kVAx(1+1)L.TR2

11kV

11.5F-11.25F-11.OR-10.75F-10.5F kV

RDf3

600A252H2VCB 12kV

25kA

CTx220/5A

60mm23Cx1 OC

2

WH1

W1

A1

150mm21Cx1

3φ300kVAS.TR

11.OR-10.5-11.0kV/400-230V1Cx3250mm2

STATION SERVICE

VCB252H1

CT

60mm23Cx1

ASSAME

RIGHT

S.TR

150mm21Cx1

1Cx3250mm2

600A252L1VCB 12kV

25kA

CTx215-75 OC

2

WH1

W1

A1

/5A

60mm23Cx1 ZCTx1

200A/1.5mA

DS 3Px1389-1

12kV 600A

LAx3

DOTACHA INTAKE

DG1

600A252L2VCB 12kV

25kA

CTx215-75 OC

2

WH1

W1

A1

/5A

60mm23Cx1 ZCTx1

200A/1.5mA

DS 3Px1389-2

12kV 600A

LAx3

LOIKAW

DG1

600A252L3VCB 12kV

25kA

CTx215-75 OC

2

WH1

W1

A1

/5A

60mm23Cx1 ZCTx1

200A/1.5mA

DS 3Px1389-2

12kV 600A

LAx3

DG1

RV1

V1

UV1

OVG1

VG1

11kV BUS

11kV

3

110V

3/

110V

3/

3φ GPT

LAWPITA P/STIE LINE

52H-1VCB 12kV

250mm21Cx3

60mm21Cx3

L.TR1

289-1DS 3Px1

12kV 600A

CTx3150-75/5A

CTx3 150-75/5A

ASSAME

RIGHT

STATION SERVICE

289-2DS 3Px1

12kV 600A

Direct Connection



Step 3: Replacement of the existing LV switchgear and installation of a new DC battery charger at the position of the existing LV switchgear.

Step 4: Replacement of the existing DC battery charger and installation of a new DC panel at the position of the existing DC battery charger.

12.1.3 Gates and Penstock

Water leakage from expansion joints of the Penstock was found. Therefore, the damaged rubber seal shall be replaced. Stoppage of 2 units and dewatering of the penstock are required for replacement of the seal.

Rehabilitation of gates and valves are minor works without shutdown of units.



Sedawgyi Hydropower Plant

12.2.1 Turbine, Generator and Control Protection System

The rehabilitation works are planned by the following basic policies in consideration of the demand and supply situation of electricity in Myanmar.

Tentative number of workers provided by EPGE required for rehabilitation works is given in Table 12.2-1 for Sedawgyi HPP.

(1) One turbine and generator (unit) are possible to be stopped from July to February for 8 months.

(2) The rehabilitation works are implemented one unit by one unit during this period.

(3) Because the penstock is dewatered when the rehabilitation work of turbine and generator is conducted, necessary countermeasures must be finished before the commencement (refer to Section 12.2.3).

(4) The overhead crane must be inspected by a crane manufacture soon after a contract between EPGE and the Contractor. If it is judged by the inspection that any components are necessary to be replaced, the new components must be provided from the crane manufacturer and the replacement work must be finished by EPGE under the supervisor from the manufacturer before the rehabilitation works of turbine and generator.

(5) When stoppage of both units is necessary by the rehabilitation works, it is shortened as much as possible.

(6) Necessary measures are conducted at the beginning of the rehabilitation works in order to minimize the influence to the operation unit by stopping the rehabilitated unit.

(7) The changes from the existing control and protection system to a new system are conducted before the dry test starts.

(8) The replacement of the generator stator coil is conducted at the existing stator setting location by building a scaffolding for disassembly, assembly and installation works.

(9) Because the large parts of the turbine can’t be lifted into the turbine pit through the inside of the stator during stator coil replacement work, the rehabilitation work of the turbine is conducted after stator coil work.



Table 12.2-1 Rehabilitation Work Schedule of Sedawgyi HPP (1 unit)

12.2.2 Substation, Transmission Line and Station Service Facilities

(1) In order to secure the power supply from 132kV system to station service during the rehabilitation works, the following procedures are recommended for replacement of 132 kV outdoor switchgear.

Step 1: Before carrying out the rehabilitation works of outdoor 132 kV switchgear, construction of new gantry structures, extension of 132 kV busbar, installation of an additional 132/11kV transformer and switchgear shall be done.

Step 2: In order to continue the operation of 132 kV T/L from Mandalay region to the northern area, jumper consisting of the gantry and conductor shall be installed as temporary work at the section between the terminal and second tower from Sedawgyi HPP.

Additionally, temporary cables from the connection points of jumpers to the disconnector switch which is installed in Step 1 shall be installed. Then, the station service power can be supplied without going through the existing 132 kV outdoor switchyard.

Step 3: From the viewpoint of equipment arrangement, 132 kV switchgear of transformer bay for Unit No.2 and T/L bay for the northern area shall be replaced by priority. After completion of replacement, the station service power will also be supplied from 132 kV system and Unit No.2 generator.

Step 4: After completion of Step 3 work, remaining existing 132 kV switchyard i.e. transformer bay for Unit No.1 and T/L bay for Mandalay circuit shall be replaced.

Step 5: After completion to replace existing 132 kV outdoor switchgear, jumpers constructed in Step 1 shall be removed.

month -2 -1 1 2 3 4 5 6 7 8【Hydropower Plant】Repair of Overhead craneDisassembling of generator and turbineStator coil disassembly and assemblyRehabilitation/maintenance work on turbineRehabilitation/maintenance work on generatorAssembly of turbineAssembly of generatorDry test of turbine and generatiorReplacement of control system (including GOV & AVR)Chage of control & protection systemsDry test of control systemWet test

【Substaion facilities】WorksTest and Commissioning

【Station Service facilities】WorksTest and Commissioning

Scheduled shutdown of 1 UnitScheduled shutdown of 2 Units for Power plant rehabilitationScheduled shutdown of 2 Units for S/S and T/L rehabilitation

Work item

critical path

completion of repair



Fig. 12.2-1 Construction Procedure for Replacement of 132 kV Outdoor Switchgear

in Sedawgyi HPP (STEP 2)

Fig. 12.2-2 Image of Jumper for 132 kV T/L

BCT

MTr. #1132/11kV

GCB

Gen. #2To Station

Service

BCT

GCB

Gen. #1

GCB

132kV Busbar

LA LA

DS DS

To StationService

DS

DS+ES

CVT

GCB

DS

DS+ES

CVT

To Aungpinlae S/S To Letpanhla S/S

MTr. #2132/11kV

BCT

LTr132/11kV

GCB

To StationService

LA

DS

Busbar Extension

Jumper

Power Flow

Open Circuit

Underground Cable

Terminal tower to Mandalay

Terminal tower to Northern area

Approx. 50 m

30 m

Temporary gantry structure 1

Temporary gantry structure 2

HDCC or AAC

Temporary Equipment

Existing

Insulation Clearance : 3.6 m



Fig. 12.2-3 Construction Procedure for Replacement of 132 kV Outdoor Switchgear


BCT

MTr. #1132/11kV

GCB

Gen. #2To Station

Service

BCT

GCB

Gen. #1

GCB

132kV Busbar

LA LA

DS DS

To StationService

DS

DS+ES

CVT

GCB

DS

DS+ES

CVT


MTr. #2132/11kV

BCT

LTr132/11kV

GCB

To StationService

LA

DS

Busbar Extension

Jumper

Power Flow

Open Circuit

Underground Cable

REP

LA

CEM

EN

T



Fig. 12.2-4 Construction procedure for Replacement of 132 kV Outdoor Switchgear


BCT

MTr. #1132/11kV

GCB

Gen. #2To Station

Service

BCT

GCB

Gen. #1

GCB

132kV Busbar

LA LA

DS DS

To StationService

DS

DS+ES

CVT

GCB

DS

DS+ES

CVT


MTr. #2132/11kV

BCT

LTr132/11kV

GCB

To StationService

LA

DS

Busbar Extension

Jumper

Power Flow

Open Circuit

Underground Cable

REP

LA

CEM

EN

T



Fig. 12.2-5 Construction procedure for Replacement of 132 kV Outdoor Switchgear


(2) As mentioned in the above, the rehabilitation work of 132 kV switchgear including a generator transformer shall be conducted in each switchyard bay one by one. Additionally, it should be noted to secure the insulation clearance from live-parts during the rehabilitation works.

(3) In order to reduce the changing-over time during rehabilitation works, a new 11 kV switchgear and 400 V AC house equipment shall be installed at an empty space in EL.100.93 as precedent work. After completion of installation of new equipment, the connection of 11 kV and other power cables shall be changed from existing equipment.

(4) The rehabilitation work of station service equipment such as 400 V AC house equipment, DC battery charger, and emergency diesel generator shall be done before changing of control and protection system.

(5) During connection and removal works of jumpers for 132 kV T/L, the generating power in Sedawgyi HPP will not be able to transmit its electricity. Additionally, generator Unit 2 shall be stopped its operation during rehabilitation works of 132 kV switchgear at Unit 2 transformer bay. Total period can be estimated about 3 months.

BCT

MTr. #1132/11kV

GCB

Gen. #2To Station

Service

BCT

GCB

Gen. #1

GCB

132kV Busbar

LA LA

DS DS

To StationService

DS

DS+ES

CVT

GCB

DS

DS+ES

CVT


MTr. #2132/11kV

BCT

LTr132/11kV

GCB

To StationService

LA

DS

Busbar Extension

Jumper (Remove)



12.2.3 Gate Facilities

(1) Events during the Survey

Regarding the gate facilities of Sedawgyi HPP such as maintenance gates, penstock gates and spillway gates, several ups and downs were occurred through the identification of the facilities to be rehabilitated during the Survey period as shown in Table 12.2-2.

Table 12.2-2 Events Regarding the Gate Facilities of Sedawgyi HPP during the Survey

Facility Maintenance Gate Penstock Gate Spillway Gate

Jurisdiction ID Owner: ID Operation: EPGE ID

1st Site Investigation (Jan. 2016)

As large amount of leakage occurred during the dewatering operation for unit 1, it was worried to conduct internal inspection of turbine during the 2nd site investigation. Repair works to stop the leakage were requested to ID.

2nd Site Investigation (Feb. 2016)

Internal inspection for unit 2 turbine was conducted successfully after the gate closure operation. Repair works for unit 1 were planned to be conducted by ID in June 2016.

It was found that both of the gates have not been functioned properly due to leakage problem since the commencement of commercial operation.

It was found that gate No.1 and No.7 could not be fully open and therefore decrease in discharging capacity was worried from the viewpoint of dam safety.

3rd Site Investigation (May 2016)

A meeting among ID, EPGE, JICA and JICA Survey Team was held in Naypyidaw. The Survey Team announced that they would conduct the site investigation of penstock gates after the completion of repair works by ID in June 2016 to stop the leakage from maintenance gate for unit 1. The Survey Team also requested permission to ID to conduct the site investigation of spillway gates from the viewpoint of dam safety.

4th Site Investigation (Jun. 2016)

As the water level of the reservoir in June 2016 was re-rose and approached to nearly FWL due to unexpected volume of inflow caused by heavy rain, ID could not conduct the repair works of maintenance gates and therefore JICA Survey Team gave up internal inspection for unit 1turbine.

JICA Survey Team could not access to penstock gates for site inspection to confirm the cause of leakage problem due to high water level of the reservoir. However it is considered that rehabilitation of penstock gates will be necessary for the extension on lifetime of HPP, therefore rehabilitation cost at the time of the Survey was estimated based on total replacement of 2 gates.

Gate No.7 was checked and repaired by ID in June 2016, therefore currently 6 gates (No.2 to No.7) are able to fully open and have enough discharging capacity for designed flood operation. As a result, spillway gates were agreed to deselect from the facilities to be rehabilitated. Although gate No.1 still have a gate opening problem, it will be repaired by ID after the rainy season.

(after the Survey)

Rehabilitation Project

Implementation of the repair works by ID shall be monitored. (In case ID will not be able to conduct the repair works, necessary countermeasures such as temporary works by the Project shall be considered.)

It is required to re-evaluate rehabilitation items in the Survey based on the site investigation after the repair works of the maintenance gate for unit 1 by ID.



(2) Penstock Gates

According to the hearing of operators and mentioned in Table 12.2-2, penstock gates are suspected of functional defection. However during this preparatory survey, the site investigation of penstock gates could not be carried out due to much amount of water leakage from concrete cracks in the upper side of the maintenance gate (stoplog). At the preliminary design stage, actual conditions of civil structures, gate leaves and guide frames shall be surveyed and drawings shall be prepared because the as-built drawings are not available.

For the rehabilitation works of penstock gates, it is assumed that 2 sets of gate leaf, guide frame, hoist and local control panel are to be replaced to new ones. The remote control function shall be included in the control system at the power plant.

Table 12.2-3 Tentative Rehabilitation Work Schedule for Penstock gate of Sedawgyi Dam (1 unit)

Work item month -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7 8Penstock gateDesignPurchase of raw materials, FabricationTransportation (to the site）Removal and Installation of Spillway gateTest

Scheduled shutdown of 1 Unit

Chapter 13 Final Report Project Implementation Plan and Schedule


CHAPTER 13

PROJECT IMPLEMENTATION PLAN AND SCHEDULE



Chapter 13 Project Implementation Plan and Schedule

Project Implementation Plan

13.1.1 Procurement Plan

Purpose of Hydropower Plants Rehabilitation Project (the Project) is to rehabilitate the Baluchaung No.1 and Sedawgyi HPPs (Hydropower Plants). Procurement plan of equipment has been discussed between EPGE (Electric Power Generation Enterprise) and JICA (Japan International Cooperation Agency) Survey Team. Existing generating equipment was originally supplied by Japanese manufacturers. The equipment to be replaced totally or partially under this rehabilitation works requires to completely make a technical interface with the existing equipment and to be designed in cooperation with specifications of the existing relevant equipment.

Recommended procurement plan of each rehabilitation equipment/facilities is given in the following section.

13.1.2 Implementation Plan

The rehabilitation works cover turbines, generators, control and protection system, relevant substation and transmission line facilities, gates and penstock and auxiliary equipment at Baluchaung No.1 and Sedawgyi HPPs. All the equipment / facilities of both HPPs were carefully examined in this Survey by various engineering experts and EPGE staff. Based on inspection results, collected data and information and so on, the objective rehabilitation equipment / facilities were selected and finalized based on close discussion between EPGE and JICA Survey Team.

As it is necessary for both HPPs to continue the operation of one unit even during the rehabilitation period, the rehabilitation works shall be carried out one (1) unit by 1 unit between July and February for eight (8) months. Another unit shall operate and generate electricity continuously.

Especially, the complete shutdown of T/L is also inevitable when the rehabilitation of equipment relating to T/L facilities is conducted. Optimum countermeasures shall be considered in order to minimize the time of full (both units) shut down.

Regarding installation works, EPGE will provide engineers and workers and take a share in rehabilitation works. In this connection, necessary EPGE’s budget shall be allocated and sufficient manpower shall be dispatched timely for smooth and efficient construction. Total number of engineers and workers required for rehabilitation works of generating equipment and S/S and T/L facilities are around 50 per each HPP.

Chapter 13 Project Implementation Plan and Schedule Final Report


Implementation Structure Plan

EPGE will be the implementation agency of this Project and will organize PMU (Project Management Unit) for implementation of the Project as shown in Fig. 13.2-1.

Deputy Chief Engineer of EPGE head office at Naypyidaw will be assigned as the Project Director and head office shall support to arrange sufficient manpower and budget required for the Project implementation. The Project will be headed by each plant manager of Baluchaung No.1 and Sedawgyi HPPs, who will be assigned as the Project Manager having responsibilities for overall management. A head electrical engineer and a head mechanical engineer of each power plant will be assigned under each Project Manager.

There are experienced electrical engineers, mechanical engineers and technical staffs who engaged in rehabilitation works at Baluchaung No.2 HPP. The rehabilitation works will be carried out by such experienced engineers and workers provided by EPGE under supervision of the Contractors’ engineers.

Fig. 13.2-1 Organization of Project Management Unit

for Implementation of the Rehabilitation Project

Executive Engineer (1)

Sedawgyi Hydropower plant

Project Director Dy. Chief Engineer (1)

Baluchaung No.1 Hydropower plant

Superintending Engineer (1)

Report Support

Coordination



Work Contents of Implementation Agency, Consultant and Contractor

The following works will be implemented by the implementation agency (EPGE), the Consultant and the Contractors.

(1) Implementation Agency of Myanmar (EPGE)

EPGE shall allot the following roles during project implementation.

1) Organizing a PMU for the Project implementation,

2) Coordination among the related ministries for smooth implementation of the Project,

3) Preparation of land for stockyards, storage facilities, lodgings for the Consultant and Contractor,

4) To provide the storage buildings /yards for discarded equipment containing hazardous wastes,

5) Prior securing of the ECC (Environmental Complaisance Certificate) for the Project from the MONREC (Ministry of Natural Resources and Environment Conservation),

6) Conduct Project monitoring according to EMP (Environmental Management Plan)

7) All necessary certificates to start the rehabilitation works for the Project,

8) Appointment of the Consultant, and cooperation with /assistance to the Consultant,

9) Close communication with institution(s) of the Project fund on bidding, contracts, procurement, project progress, and other information,

10) Proper actions for necessary procedures on equipment and materials import for the Project,

11) Issue of payment certificates for the Consultant and Contractors,

12) Claim management of Contractors, local people and others,

13) Prosecution of the commissioning test of the Project,

14) Training of employees for O&M (operation and maintenance) for turbine, generator, control and protection system and S/S and T/L facilities,

15) Proper O&M of the equipment/facilities after commissioned,

16) To complete works required for rehabilitation Project such as NDT (Non Destructive Test for turbines), repair works of damaged foundation, steel structures in S/S etc. conducted by EPGE in due course,

17) To coordinate and push ID (Irrigation Department) to carry out leakage measure works for concrete cracks in the upper side of the maintenance gate (stoplog) of Sedawgyi Dam in order to conduct field survey of penstock gates in preliminary design.

18) To provide engineers and workers for rehabilitation works under supervision of Contractors’ engineers (around 40 ~ 50 staffs for each power plant), and

19) To secure budget and manpower to execute the above matters.



(2) Project Consultants

The Consultants shall allot the following particulars.

1) Preliminary design related to preparation of bid documents for the Project including a field survey and investigation,

2) Preparation of the design report for the Rehabilitation Project and submission to EPGE,

3) Preparation of the bid documents for the Rehabilitation Project and submission to EPGE,

4) Evaluation of proposals forwarded by bidders and assistance to EPGE evaluation committee in selecting prospective bidders for the contracts,

5) Assistance to EPGE in contract negotiations with prospective bidders and in conclusion of the contracts,

6) Examination on manufacturing/working drawings and various communications from the Contractors for approval,

7) Inspections and tests for equipment / materials to be carried out at the contractors’ factories prior to shipment,

8) Project management and supervision of the Contractors’ works,

9) Preparation of the monthly reports, to conduct meetings, safety patrols with the Client and the Contractor,

10) Preparation of the completion report for the Project and submission to EPGE,

11) To review and confirm the inspection reports prepared by the Contractor including cost estimates for overhead crane, guide vanes for approval of the Client,

12) To conduct Soft Component for capacity building coordinating with O&M training by the Contractor,

13) Inspection on facilities immediately prior to expiration of the guarantee period for facilities and

14) Transfer of knowledge to EPGE staff in charge of the Project.

(3) Contractors

The Contractors shall allot the following works.

1) Implementation of design for the Project based on site condition, 2) Design/manufacturing/procurement and tests of the equipment/facilities/materials, 3) Installation of equipment/facilities and the factory test 4) Verification of proper functions of all the facilities completed, 5) Commissioning of the equipment/facilities to EPGE, 6) Transfer of knowledge to EPGE through their working period for construction, maintenance

and operation of the project facilities.

(4) Responsible Activities for EPGE and Relevant Agencies and their Deadline

In order to implement this Project successfully, the following activities shall be conducted by EPGE and/or relevant agencies responsibly by the deadline.



Equipment / Facilities Responsible agency Deadline

(1) Baluchaung No.1 HPP Repair of access road EPGE Before transportation of

equipment, materials etc. Preparation of stockyards and ware houses EPGE Before transportation of

equipment, materials etc. Provision of the storage buildings/yards for discarded equipment containing hazardous wastes

EPGE Before commencement of works

Provision of site lodging houses and offices for the Consultant and Contractor staff

EPGE immediately after the conclusion of the Contract

Inspection and repair of station over-head crane (EPGE workers conduct repair works under supervision of the manufacturer engineer checked by the Consultant. The Consultant makes judgement of repair items of over-head crane based on the results of joint inspection, reports to and obtains approval from EPGE)

Lot-1 Contractor

Before the commencement of installation works of E/M equipment

NDT (Non Destructive Test) (EPGE workers conduct NDT under supervision of the Contractor)

EPGE During Overhaul and inspection

Procurement of Potable extinguishers EPGE Immediately after budget allocation

Rehabilitation of brake system of the generator EPGE Immediately after budget allocation (During Overhaul and inspection is preferable)

Repair of steel structures of 132kV circuit breaker (based on original design)

EPGE Before the commencement of installation works of S/S

Repair of foundation of surge arrestors in phase B (based on original design)

EPGE Before the commencement of installation works

Repair of concrete fences around the pondage EPGE Immediately after budget allocation

Cleaning of the inside of existing pipes including embedded pipes EPGE During Overhaul and inspection

Repair of painting on flowing water surface and outside of the turbine EPGE During Overhaul and inspection

Temporary works for station service supply from 11kV during rehabilitation works for S/S (detailed specification of temporary power supply is examined during bid document preparation stage)


(2) Sedawgyi HPP Repair of access road EPGE Before transportation

equipment, materials etc. Preparation of stockyards and ware houses EPGE Before transportation

equipment, materials etc. Provision of the storage buildings /yards for discarded equipment containing hazardous wastes

EPGE Before commencement of works

Inspection and repair of station over-head crane (EPGE workers conduct repair works under supervision of the manufacturer engineer checked by the Consultant. The Consultant makes judgement of repair items of over-head crane based on the results of joint inspection, reports to and obtains approval from EPGE)

Lot-2 Contractor

Before the commencement of installation works of E/M equipment

Provision of site lodging houses and offices for the Consultant and Contractor staff

EPGE immediately after the conclusion of the Contract

NDT (Non Destructive Test) (EPGE workers conduct NDT under supervision of the Contractor)

Lot-2 Contractor

Before the commencement of installation works

Procurement of Potable extinguishers EPGE Immediately after budget allocation



Equipment / Facilities Responsible agency Deadline

Repair of station communication system EPGE Immediately after budget allocation

Rehabilitation of a heater of a generator EPGE Immediately after budget allocation (During Overhaul and inspection is preferable)

Cleaning of the inside of existing pipes including embedded pipes EPGE During Overhaul and inspection

Repair of painting on flowing water surface and outside of the turbine EPGE During Overhaul and inspection

Repair of control board of a gantry crane for draft tube gates. EPGE Immediately after budget allocation

Temporary works for station service supply from 132kv T/L system during rehabilitation works for S/S (detailed specification of temporary power supply is examined during bid document preparation stage)


(3) Sedawgyi Dam Countermeasure works for leakage from concrete cracks in the upper side of the maintenance gate (stoplog)

ID- Before preliminary design stage

Staffing Plan of the Project

The following staffs from EPGE and the Consultant will carry out the Project.

(1) Implementation Agency of Myanmar (EPGE)

1) Project Director of the EPGE head office is to be assigned throughout the whole project period.

2) Project Manager of the EPGE’s project office (power plant) is to be assigned throughout the whole project period. (He will also be a counterpart of the Consultant.)

3) EPGE’s staffs for monitoring environmental measures are to be timely dispatched to the sites.

4) On-the-job training participants for the O&M of each power plant under the Project are provided.

(2) Consultant

• Preliminary Design and Preparation of Bid Documents The Consultant will execute the preliminary design for the Rehabilitation Project through discussions with EPGE and in accordance with results of the field survey. The Consultant will produce bid documents for the Project.

• Bid and Contract The Consultant will carry out assistance to EPGE during announcements of the bid, bid opening, bid evaluation, contract negotiation and preparation of the contract documents.

• Procurement Management The Consultants will manage all works for examinations on the Contractors’ drawings and designs, and inspection/tests of equipment/materials at the Contractors’ factory.



• Supervision of Contractors’ Works Through the whole period of the Contractors’ works, the Consultant will supervise all the works. The Consultant will have responsibility for training of EPGE’s operators and maintenance staff for equipment / facilities after completion of the Rehabilitation Works.

• Commissioning Test and Inspection for Defect Liability Period After completion of the rehabilitation works of all equipment / facilities, the Consultant will supervise the Contractors’ commissioning tests, Furthermore, the Consultant will check and approve the project completion report of the completed facilities to be submitted by the Contractors, and assist EPGE with their procedures for issuing the taking-over certificates to the Contractors. Immediately before the expiration of the defect liability period of the Rehabilitation equipment/facilities, the Consultant in conjunction with EPGE will inspect all the project-related facilities to issue the final certificates to the Contractors.

• Soft Component for the O&M Capacity Development The both hydropower plants have been operating and maintaining for around 30 years, however overhaul of generating equipment has not been conducted so far and also appropriate maintenance and required replacement have not been done. In this connection, proper and appropriate O&M are essential to keep in good condition and achieve longer life time of equipment / facilities, so soft component shall be carried out to develop capacity building for operators and maintenance staffs of each station.



Project Implementation Schedule

The implementation of the rehabilitation project of Baluchaung No.1 and Sedawgyi HPPs is shown in Fig. 13.5-1.

During the Survey, site inspection of the penstock gates of Sedawgyi Dam could not be carried out in order to confirm whether their function is normal or not. In the worst case, it will take additional 2 years to replace 2 penstock gates because 8 months of the stoppage of 1 unit is required for removal, installation and test of the gate. After commissioning of rehabilitation works of Sedawgyi HPP, rehabilitation works of penstock gates will start. During the next preliminary design stage, inspection and survey of penstock gates shall be done and preliminary design is to be conducted based on the results. Implementation plan / schedule and rehabilitation cost would be examined if rehabilitation works of the gates would be necessary.

Fig. 13.5-1 Implementation Schedule for the Rehabilitation Project of Baluchaung No.1 and

Sedawgyi HPPs

Item Year 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026Month 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112 12 3456 789101112

Selection of Consultant 12.0Consulting Service for Sedawgyi HPP

Preliminary Design 6.0Tender (Incl. Bid Preparation and Evaluation) 12.0Construction Supervision 39.0

Construction Schedule of Sedawgyi HPP1st Unit 27.02nd Unit 39.0S/S, T/L 12.0Penstock Gate No.1 of Sedawgyi dam 25.0Penstock Gate No.2 of Sedawgyi dam 25.0

Consulting Service for Baluchaung No.1 HPPPreliminary Design 3.0Tender (Incl. Preparation and Evaluation) 12.0Construction Supervision 34.0

Construction Schedule of Baluchaung No.1 HPP1st Unit 22.02nd Unit 34.0S/S, T/L 11.0

Defect Liability Period: 12.0 Month

Soft Component: 2.0 Month

Defect Liability Period: 12.0 Month

Soft Component: 2.0 Month

Stop

Stop

Stop

Stop

Stop

Stop



O&M Plan

13.6.1 Current O&M Organization

(1) Head Office

GOM (Government of Myanmar) announced on March 17th, 2016 that existing thirty six (36) ministries were reformed to twenty one (21) ministries and MOEP (Ministry of Electric Power) and MOE (Ministry of Energy) was merged into MOEE (Ministry of Electricity and Energy). Organization chart of MOEE is shown in Fig. 13.6-1.

EPGE has responsibility for O&M of existing power plants. At present total 27 hydropower plants all over the Myanmar are operated and maintained by EPGE. Organization chart of EPGE is shown in Fig. 13.6-2.

Fig. 13.6-1 Organization of MOEE

Fig. 13.6-2 Organization of EPGE

MinisterU Pe Zin Tun

Permanent SecretaryU Htain Lwin

Energy Electric Power

Myanmar Oil & Gas Enterprise (MOGE)

U Myo Myint Oo (MD)

Myanmar Petrochemical Enterprise

(MPE)U Thant Sin (MD)

Myanmar Petroleum Products Enterprise

(MPPE)U Thant Sin (MD)

Department of Hydro Power Implementation

(DHPI)U Aye San (DG)

Mandalay Electricity Supply Corporation

(MESC)U Thein Hlaing (CEO)

Department of Electric Power Planning

(DEPP)Daw Mi Mi Khine (DG)

Electric Power Generation Enterprise

(EPGE)U Khin Maung Win

(MD)

Electricity Supply Enterprise

(ESE)U Myint Aung (MD)

Power Transmission and System Control

Department (PTSCD)U Htain Lwin (DG)

Yangon Electricity Supply Corporation

(YESC)U Htun Kywe (CEO)



(2) Baluchaung No.1 HPP

Organization of Baluchaung No.1 HPP consists of total of 71 staff as shown in Fig. 13.6-3. Baluchaung No.2 HPP is located in the downstream of Baluchaung No.1 HPP and mutual communication of both HPPs is executed.

Fig. 13.6-3 Organization of Baluchaung No.1 HPP

(3) Sedawgi HPP

Organization of Sedawgyi HPP consists of total of 49 staff as shown in Fig. 13.6-4. Basically, operation of the power plant depends on requirement of irrigation water in the downstream decided by Irrigation Department (ID).

Source: JICA Survey Team

Fig. 13.6-4 Organization of Sedawgyi HPP

Shift (C), Shift (D), Electrical Maintenance

Station Manager (1)

Head of Department Mechanical (22) Shift (A), Shift (B), Mechanical Maintenance, Intake & Poundage

Head of Department Electrical (21)

Head of Department Vehicle (4)

Branch Clerk (8)

Accountant (3)

Store Keeper (2)

Security (2)

Daily Worker Charge (8) Source: JICA Survey Team

Station Manager (1)

Head of Electrical Section (4)

Electrical Maintenance Head of Operation Section (6)

Head of Mechanical Section (11)

Computer Section (3)

Admin Section (6)

Account Section (2)

Procurement Section (1)

Shift (A) (8)

Shift (B), Mechanical Maintenance

Shift (D) (7)

Shift (C)



13.6.2 O&M Plan

EPGE has responsibilities of O&M of own hydropower plants all over the country. Daily O&M, minor repair and replacement are carries out by power plant staffs under supervise and management of plant manager and engineers.

Major repair and replacement of damaged equipment / facilities are used to be budgeted and managed by the head quarter.

The experienced O&M staffs have enough technical skill for O&M of existing hydropower plants, however due to budget shortage of maintenance, lack of spare parts, improper management, and lack of technologies. Therefore it is difficult to say that proper and appropriate maintenance is being carried out at present.

Considering the above-mentioned situations, sustainable equipment supply and management plan based on the concept of preventive maintenance shall be introduced in order to keep equipment / facilities in good condition, manage proper storage of spare parts, and realize them longer lifetime. Recommended inspection schedule for preventive maintenance is shown in Table 13.6-1. During each inspection, relevant equipment must stop (blackout) and for turbines internal inspection will be done after dewatering of the penstock.

Table 13.6-1 Recommended Inspection Schedule for Preventive Maintenance

Equipment

Year Turbine Generator Control

system Main

transformer Switch gear other equipment

1st year ○ ○ ○ ○ ○ ○

2nd year ○ ○ ○ ○ ○ ○

3rd year ◎ ◎ ◎ ◎ ◎ ◎

4th year ○ ○ ○ ○ ○ ○

5th year ○ ○ ○ ○ ○ ○

6th year ◎ ◎ ◎ ◎ ◎ ◎

7th year ○ ○ ○ ○ ○ ○

8th year ○ ○ ○ ○ ○ ○

9th year ◎ ◎ ◎ ◎ ◎ ◎

10th year ● ● ○ ○ ○ ○

11th year ○ ○ ○ ○ ○ ○

12th year ○ ○ ○ ● ● ◎

○: Annual inspection by visual inspection of equipment / facilities ◎: Triennial inspection by visual inspection, in addition by measurement of specific items by using measuring

instruments. ●: For generating equipment such as turbines and generators, internal inspection of specific items by overhaul per

decade, and necessary repair and replacement of worn aged deteriorated spare parts. For main transformers, breakers etc. internal inspection of specific items by partial overhaul per 12 years, and necessary repair and replacement of worn aged deteriorated spare parts.

The recommendations on effective O&M are as follows:



(1) Management of spare parts

JICA Survey Team confirmed that spare parts inventory has been updated whenever spare parts were used at both hydropower plants. However, the team confirmed that spare parts were not restocked after all spare parts were utilized. It results that if troubles of equipment would occur, it might affect generation of power plants due to lack of necessary spare parts.

Original manufactures might not store equipment and spare parts for longer period, generally 10 to 20 years. In this connection, it is necessary to establish management process such that it shall be checked whether spare parts could be produced or not prior to the possible delivery time of necessary spare parts and these spare parts would be purchased as required.

Also, it was found that some of spare parts are not stored in appropriate condition environmentally. For example, there are spare parts of electronic devices required for temperature control. If these spare parts might be stored in locations subject to high temperature and humidity, performance of spare parts might be lost. In addition, there are spare parts which shall be stored in conditions free from dust and dirt. If these spare parts might be stored without wrapping by vinyl sheets and as they are, performance of spare parts might be lost.

Considering the above situation, it is necessary for management of spare parts how to store spare parts and how to keep in appropriate conditions.

(2) Secure implementation of Maintenance

O&M manual was produced during the construction period and provided for both power plants. However, periodical maintenance works with stoppage of a unit have never been carried out since the commencement of generation.

Such maintenance condition will cause difficulties to find out aged deterioration and possible troubles of equipment before something happens and to conduct repair and replacement timely and to keep reliability of generating facilities. As a result, countermeasures might be made after troubles occur and it might cause to shorten generating hours and decrease generating energy production.

Considering the above situation, it is necessary for management of maintenance to check whether periodical maintenance works including overhaul base on O&M manual after these rehabilitation works.

(3) Finding out timing of rehabilitation of facilities

In Japan, diagnosing technologies of equipment / facilities are being adopted largely in order to find out proper timing of replacement of equipment / facilities. So far replacement timing of equipment / facilities has been determined by uniform replacement cycle, but by means of this new method progress of aged deterioration can be checked, so their lifetime becomes longer. Also, equipment / facilities which aged deterioration is making progress will be replaced by evaluating replacement timing based on progress of their aged deterioration.

Representative examples are diagnosing of a stator coil of generators, main transformer, power cables and so on. It is very useful to transfer these diagnosing technologies to Myanmar.

(4) Management of as-built drawings of equipment / facilities

At present, all drawings and reports of equipment / facilities are stored in a storeroom, but they



are not organized and registered, so it is very difficult to find out necessary ones.

It is recommended to establish effective management system of drawings. Suitable store location of drawings shall be considered. For example, copies of drawings which are used whenever troubles of equipment occur shall be stored in the control room.

(5) Management of machine tools

Machine tools including special tools which were delivered initially during construction are not complete now. Necessary tools become private ones and when troubles of equipment occur repair works were done by private tools, therefore some of repair works were done by using inappropriate tools.

In order to avoid this situation, it is recommended to establish storage and quantity management of machine tools.

(6) Documentation of regular inspection records

Internal inspection of hydraulic turbines involving dewatering shall be carried out once per year. It takes several days for such inspection to stop the generation per unit. It is useful for establishment of future maintenance plan and schedule to keep all documents of inspection records with photographs of major parts of equipment during internal inspection. The inspection records prepared by JICA Survey Team can be referred.

If some defects, damages, troubles etc. are found out, photographs of those parts shall be taken and dimensions of such parts are measured as much as possible. For example, if erosion of a runner vane due to cavitation is found out, it is possible to make future schedule of repair by means of welding by recording erosion scale (width, length, depth)

Chapter 14 Final Report Economic and Financial Analysis


CHAPTER 14

ECONOMIC AND FINANCIAL ANALYSIS



Chapter 14 Economic and Financial Analysis This Chapter first calculates the IRR (Internal Rate of Return) and NPV (Net Present Value) to justify the implementation of the Project from the financial and economic perspectives. Secondly, the financial situation of the implementing organization and relevant organizations for the Project under the MOEE (Ministry of Electricity and Energy) is described and analyzed.

Objectives and Methodology of the Financial Analysis and Economic Analyses

The financial and economic analyses aim to examine the viability of the Project by calculating the IRR and the NPV.

Financial analysis is conducted to evaluate the profitability of the Project from the viewpoint of the implementing organization. To obtain the FIRR (Financial Internal Rate of Return) and the FNPV (Financial Net Present Value), net benefit of the project is calculated considering 1) the benefits i.e., incremental revenue of tariff from the Project and 2) the cost based on the market price. Financial cost excludes price escalation, IDC (Interest During Construction), and other financial charges from the project cost. FIRR and FNPV are calculated based on the cash flow before interest payments.

Economic analysis is conducted to evaluate the viability of the Project from the viewpoint of the national economy. To obtain the EIRR (Economic Internal Rate of Return) and the ENPV (Economic Net Present Value), the benefit of the Project is calculated considering 1) the increased benefit based on the saved cost by replacing alternative energy sources (e.g., diesel generators) and 2) the economic costs.

In the EIRR and ENPV calculation, the cost of the Project is converted to economic cost in order to evaluate the actual cost for the national economy. In this regard, the transfer payment within the national economy (e.g., tax) is excluded from the calculation as it is neither a benefit nor a cost for the country.

The cash flow of the Project is prepared to calculate the IRR and NPV. These figures are calculated based on the following formula. The IRR is equal to the cut-off rate that results in zero NPV. For the calculation of the NPV, a predetermined discount rate1 is used.

( ){ ( ) } 011

=+÷−∑=

tn

tt rCB

Where, B = Benefit, C = cost, t = tth year (1, 2, 3…n), n = project life, r = IRR

For the calculation of both the IRR and NPV, two cases, namely, “with project” and “without project”, are normally considered to determine the net incremental benefit and cost. As explained later, the foregone benefit of “without project” is taken into consideration in the analysis in order to estimate the net incremental benefit of the Project.

1 In ADB’s “Financial Management and Analysis of Projects” (2005), discount rate is defined as interest rate used to convert future receipts or

payments to their present value.

Chapter 14 Economic and Financial Analysis Final Report


Assumptions used in the Financial and Economic Analyses

This section lists and describes major assumptions that are used for calculating IRR and NPV based on the findings in the study.

14.2.1 Project Life, Salvage Value, and Price Base

The Project is assumed to have a useful economic life of 40 years2 after the completion of construction. At the end of the economic life, the Project is assumed to have no salvage value. Benefits and costs are expressed in terms of 2016 constant prices in Myanmar Kyat.

14.2.2 Tariff

In order to calculate the incremental revenue as the benefit in the financial analysis, the tariff of 18 kyat/kWh and 52 kyat/kWh is used in the calculation of the base case.

The tariff of 18 kyat/kWh is what the HPGE (Hydropower Generation Enterprise) used to receive from MEPE (Myanma Electric Power Enterprise). After the restructuring of the organizations under the MOEE, the EPGE (Electric Power Generation Enterprise) owns the HPPs (Hydropower Plants) and also functions as the single buyer of electricity. Therefore, the EPGE does not pay the money for tariff to the two HPPs, which are owned and operated by the EPGE. However, it is assumed in the financial analysis that the opportunity cost of the electricity generated by two HPPs is 18 kyat/kWh for the purpose of quantifying the financial benefit.

The tariff of 52 kyat/kWh is the selling price of electricity to the distribution companies (ESE: Electricity Supply Enterprise and MESC: Mandalay Electricity Supply Corporation).3 This tariff is also used for quantifying the incremental benefit from the viewpoint of the EPGE.

14.2.3 Overhaul Cost and Operation and Maintenance Cost

Overhaul cost is scheduled to be incurred every ten years after starting the operation of the Project. The overhaul cost is estimated to be 150 Million Kyat for each of two HPPs.4

O&M (Operation and Maintenance) cost is not taken into account in the financial and economic analysis as the cost is incurred in both cases of “with project” and “without project”, which means that there is no incremental cost for the Project.

14.2.4 Conversion Factor

The SCF (Standard Conversion Factor) is an indicator to estimate the level of distortion in the market due to policies, duties, or subsidies of the GOM (Government of Myanmar). The SCF is applied in the economic analysis when the local cost, which is assumed to be distorted, is to be converted into the economic cost in order to eliminate distortion.

The SCF is calculated as 0.99 based on the following formula, and figures from the recent terms of trade and duties. As the figure of SCF is nearly equal to one, it can be concluded that there is little distortion in the prices in the local market.

2 This assumption is also applied to the existing hydropower stations in the case of “without project”. See “15.2.7 Remaining Life of Existing

HPPs” for more detail. 3 The tariff of electricity to YESC (Yangon City Electricity Supply Corporation) is 57 kyat/kWh. The use of the tariff of 52 kyat/kWh for the

financial analysis is based on the request of the EPGE. 4 In construction schedule, Unit 1 of Baluchaung No.1 HPP and Unit 1 of Sedawgyi HPP will be rehabilitated first and Unit 2 of the former and

Unit 2 of the latter will be rehabilitated in the following year. Therefore, the overhauls cost for Unit 1 of two hydropower stations (150 million kyat) will be incurred first and that for Unit 2 (150 million Kyat) will be incurred in the following year.



SCF= [Import (CIF) + Export (FOB)] / [(Import + Import Duty) + (Export + Export Subsidy - Export Tax)]

Table 14.2-1 Terms of Trade (Unit: Million Kyat)

Import Export Import Duty Export Tax Export Subsidy SCF

13,760 11,204 307 0 0 0.99 Source: Central Statistical Organization, “Myanmar Statistical Yearbook 2015”, Table 14.01 Value of Foreign Trade, Table 17.02

Current Receipts of the State Administrative Organizations Note: Figures in the table are those of 2013/2014. Note: Figure of import duty is converted in the US dollar by using exchange rate of 1,180 kyat/US$.

Regarding labor cost, it is assumed that there are no significant distortions in the wage of skilled labor in the economic analysis. In the case of unskilled labor, although the unemployment exists in Myanmar, the percentage of unemployment is 4.0% in 2014. 5 Like the skilled labor, the distortion in the wage of unskilled labor is not assumed in the economic analysis.

14.2.5 Cut off Rate

The cut-off rate is used as a deciding factor whether the project is viable from the viewpoint of the implementing organization and the national economy, by comparing it with FIRR and EIRR, respectively.

In principle, the cut-off rate adopted in the financial analysis is calculated based on the concept of opportunity cost of capital. As the financing of the Project is not finalized yet and it is difficult to calculate the weighted average cos of capital, the rate of the treasury bill, which is 7.307%,6 is used as the opportunity cost of capital.

ADB (Asian Development Bank) used 10%-12% as the social discount rate for the economic analysis, and such rate is regarded as the social opportunity cost of capital.7 This report applies 12% for the calculation of ENPV to make the calculation of ENPV conservative.8

14.2.6 Transmission and Distribution Loss

3.1% of transmission loss and 15.6% of distribution loss are applied to calculate the net incremental sales of electricity to the end consumers and the benefit in the economic analysis.

Table 14.2-2 Transmission and Distribution Loss

Transmission loss 3.1%

Distribution loss 15.6%

Transmission & distribution loss 18.7% Source: Deloitte, "Myanmar Power Sector Financial Analysis and Viability Action Plan:

Key Findings & Recommendations", May 18, 2016, p. 7

5 Central Statistical Organization, “Myanmar Statistical Yearbook 2015”, Table 7.02 Labour Force, Labour Participation Rate and Unemployment

Rate. The figure is that of 2014 based on the result of 2014 Myanmar Population and Housing Census. 6 The figure is based on the rate of 91-day treasury bill auctioned on October 19, 2016. 7 ADB Economics and Development Resource Center, “Guideline for the Economic Analysis of Projects”, February 1997, p.37 8 The application of higher discount rate makes NPV smaller.



In the financial analysis, the transmission and distribution loss is not taken into account in the case of 18 kyat/kWh as the financial benefit is calculated based on the generated electricity reached and sold to the EPGE, not on what reached to the end users. In the case of 52 kyat/kWh, the transmission loss is taken into consideration as the electricity is calculated based on the amount that have reached the distribution companies after transmission.

14.2.7 Remaining Life of Existing HPPs

The incremental benefit is calculated by quantifying the difference in the amount of revenue (financial analysis) and economic benefit (economic analysis) between the existing units (without project) and the rehabilitated units (with project). Assumption on the remaining life of the existing hydropower stations (without project) is made in order to calculate the incremental generation, revenue, and economic benefit of the Project.

Table 14.2-3 Remaining Life of Two HPPs in the case of “Without Project”

HPP Year of starting operation Age in the year of 2016 Expected remaining life

Baluchaung No.1 1992 24 years 16 years

Sedawgyi 1989 27 years 13 years Source: Prepared by the JICA Survey Team

As the table above shows, the remaining life of the HPPs is assumed to be 16 years and 13 years for Baluchaung No.1 and Sedawgyi HPPs respectively. The assumption on the remaining life of the existing power stations is used to calculate the foregone benefit in the case of “with project”. After 40 years of operation, the existing HPPs are assumed to generate no electricity.

14.2.8 Trend of Generated Electricity in the case of “Without Project”

In order to calculate the incremental revenue in the financial and the economic benefit in the economic analysis, it is necessary to estimate the future trend of generation of the two HPPs in the case of “without project”.

Two HPPs shows the trend of declining generated electricity in the last ten years. It is hard to estimate to what extent that the degradation of the facility and equipment of the HPPs contributed to the decline of the generated electricity.



Fig. 14.2-1 Trend of Generated Electricity (Baluchaung No.1 HPP)

Source: EPGE

Fig. 14.2-2 Trend of Generated Electricity (Sedawgyi HPP)

Source: EPGE

It can be inferred that several factors such as the inflow of water may have influenced the level of generation in addition to the degradation of the facility and equipment. Although it is difficult to distinguish the impact caused by the degradation of the facility and equipment on the decline of generated electricity with that of other factors, it is assumed in the financial and economic analysis that 6.7 GWh and 5.3 GWh will decrease annually for Baluchaung No.1 and Sedawgyi HPPs respectively, based on the approximation formula in the above figures.



Financial Analysis

14.3.1 FIRR and FNPV

Benefit and cost are compiled and calculated considering the 2016 prices in order to obtain the FIRR. Moreover, the rate of the treasury bill (7.307%) is used as the discount rate for calculating the FNPV.

Table 14.3-1 FIRR and FNPV: Case of 18 kyat/kWh

FIRR FNPV (Million Kyat) FNPV (Million $)

2.09% (60,317) (51)

Source: Prepared by the JICA Survey Team

By using the discount rate of 7.307%, the FNPV for the case of 18 kyat/kWh turns into negative.9 In order to make the FNPV nearly zero and make the FIRR equal to the discount rate by the measure of increasing tariff alone, the tariff needs to be raised to nearly 47.5 Kyat/kWh, which is 2.6 times as the level of the applied tariff.10

Table 14.3-2 FIRR and FNPV: Case of 52 kyat/kWh

FIRR FNPV (Million Kyat) FNPV (Million $)

7.69% 5,990 5

Source: Prepared by the JICA Survey Team

The FNPV for the case of 52 kyat/kWh becomes positive unlike the case of 18 kyat/kWh. The result is understandable as the tariff of 52 kyat/kWh reflects the purchase cost of electricity from not only hydropower stations but also other type of power stations, whose cost is higher than hydropower stations.11

Sensitivity analysis is conducted for the financial analysis as the actual condition may be different from those assumed for the base case. In the sensitivity analysis, 1) generation increase (+10%), 2) tariff increase (+20%), 3) cost increase (+10%), and 4) delay in construction (1 year) are considered. Although the FNPV in the base case of 18 kyat/kWh is negative, it is clear from the figures in the table below that the changes in the level of benefit and cost and the delay in construction do not significantly change the level of FIRR and FNPV.

9 The World Bank report points out that the unit cost of generating electricity by the existing hydropower stations is 20-30 kyat/kWh. Therefore,

it is understandable that the use of 18 kyat/kWh for financial analysis leads to the negative present value. See “Annex 6: Financial Situation in the Power Sector” in World Bank, "International Development Association Project Appraisal Document on a Proposed Credit in the Amount of SDR 92.6 Million (US$140 Million Equivalent) to the Republic of the Union of Myanmar for Electric Power Project", August 29, 2013

10 The capacity of Baluchaung No. 1 and Sedawgyi shares only 1.8% of the total installed capacity of hydro power stations in Myanmar. As the share of these two power stations is small, the result of FIRR/FNPV does not necessarily mean that the tariff of two hydro power stations should be adjusted simply to make the FNPV positive in reality.

11 Overall financial situation of the institutions under the MOEE is analyzed in 15.5 Financial Status of the Implementing Organization.



Table 14.3-3 Sensitivity Analysis for Financial Analysis: Case of 18 kyat/kWh

Case Benefit Cost FIRR FNPV (%) (Mil Kyat) (Mil US$)

Base case No change No change 2.09% (60,317) (51)

Generation increase (+10%) +10% No change 2.59% (55,847) (47)

Tariff increase (+20%) +20% No change 2.96% (52,936) (44)

Cost increase (+10%) No change +10% 1.65% (70,022) (59)

Delay in construction (1 year) No change No change 2.09% (56,210) (47) Source: Prepared by the JICA Survey Team

The changes in the assumptions for the case of 52 kyat/kWh do not change the conclusion in that the FNPV remains positive, except the case of cost increase (+10%), which results in the small negative value. The results implies that the careful attention should be paid to cost management during construction period.

Table 14.3-4 Sensitivity Analysis for Financial Analysis: Case of 52 kyat/kWh

Case Benefit Cost FIRR FNPV (%) (Mil Kyat) (Mil US$)

Base case No change No change 7.69% 5,990 5

Generation increase (+10%) +10% No change 8.45% 18,503 16

Tariff increase (+20%) +20% No change 8.90% 26,633 22

Cost increase (+10%) No change +10% 7.09% (3,715) (3)

Delay in construction (1 year) No change No change 7.69% 5,582 5 Source: Prepared by the JICA Survey Team



Economic Analysis

In this section, the economic costs for the Project are identified first. Secondly, the economic benefit is identified and quantified based on the concept of the saved cost. Lastly, based on the assumptions, costs and benefits calculated, the EIRR and the ENPV are calculated and presented.

14.4.1 EIRR and ENPV

Based on the assumptions, costs and benefits calculated and described so far, the EIRR and ENPV are calculated and presented in this section.

(1) Base Case

The economic benefit and cost are compiled and calculated in order to obtain EIRR and are discounted using the social discount rate (12%) for attaining the ENPV.

Table 14.4-1 EIRR and ENPV

EIRR (%) ENPV (Million Kyat) ENPV (US$ million)

21.09% 117,876 99 Source: Prepared by the JICA Survey Team

The result shows that EIRR is higher than the cut-off rate in the base case. The ENPV of the Project shows positive result, while the FNPV showed negative value. It can be concluded that the economic benefit of the Project is robust as the people in Myanmar are paying high costs for alternative energy sources (i.e. diesel generators and kerosene lamp) due to insufficient supply of electricity and the Project can be justified from the viewpoint of the national economy.

(2) Sensitivity Analysis

The sensitivity analysis is conducted for economic analysis. The increase in generation, decrease in economic benefit, cost overrun of construction, and delay in construction are considered.

Table 14.4-2 Sensitivity Analysis for Economic Analysis

Case Benefit Cost EIRR ENPV (%) (Mil. Kyat) (Mil. US$)

Base case No change No change 21.09% 117,876 99

Generation increase (+10%) +10% No change 22.75% 143,221 120

Benefit decrease (-10%) -10% No change 19.96% 98,854 83

Cost increase (+10%) No change +10% 20.06% 110,648 93

Delay in construction (1 year) No change No change 21.09% 105,247 88

The impact on EIRR and ENPV of the change in the level of benefit and cost and delay in construction is relatively small with slight change of EIRR and ENPV.



Financial Status of the Implementing Organization

This section describes the financial situation of the implementing organization in charge of the Project and the relevant organizations in generation, transmission and distribution under the MOEE. First, the past financial performance and the forecast of the financial situation of the organizations are briefly described and analyzed. The major financial issues, namely tariff and subsidy, are analyzed as these issues are closely concerned with the sustainable operation of the Project and the overall operation of the power sector under MOEE.

14.5.1 Financial Situation of the Power Sector under the MOEE

As the organizations in charge of generation, transmission, and distribution of electricity under the MOEE have been recently restructured, the financial information of the newly established organizations are not available at the time of writing this report. Therefore, this section explains the past financial performance of the organizations before restructuring, HPGE in particular and the financial performance of the relevant organizations.12

HPGE used to own and operate hydropower stations and coal thermal power plants and sell the generated electricity to MEPE at 20 Kyat/kWh from 2010 to 2014, which was reduced by MOEP (Ministry of Electric Power) to 18 kyat/kWh in 2015.

HPGE has been making profits in the last six fiscal years, partly due to the fact that the majority of the assets owned by HPGE was already depreciated and a few more plants had been added as the assets of HPGE, which resulted in the low depreciation cost.

While the revenue of the entities under the MOEP increased by 40.3% from 2014 to 2015, the cost of power purchase and own generation increased more rapidly, 55.6% in the same period. As a result, the profit decreased by 39.1% from 2014 to 2015.

One of the main factors contributing to this situation is the increasing share of the gas based power plants in total generation. The purchasing cost of the electricity generated by the gas based power plants is nearly 105 kyat/kWh. On the other hand, the retail tariff for consumers is only 74.16 kyat/kWh. Therefore, the increasing share of the gas based power plants has a significant negative impact on the profit level.

14.5.2 Tariff and Subsidy

The level of tariff tends to be insufficient to cover the necessary cost in the past, though the consolidated profit is still positive partly due to the provision of the GOM’s subsidy. This situation made it difficult the organizations in charge to sustain and expand the operation and rehabilitate and upgrade the facilities and equipment by mobilizing the internally generated profit.13

The previous section explains the consolidated profit level of the organizations in recent years. However, it should be borne in mind that the GOM has been providing subsidy to support the working capital for the operation of the entities. The recent budget shows that the GOM allocated the budget for working capital for carrying out the functions of the state owned organizations under

12 The data for and the analysis of the financial performance in this section heavily depends on the following documents: Deloitte, "Myanmar

Power Sector Financial Analysis and Viability Action Plan: Inception Report ", August, 2015; Deloitte, "Myanmar Power Sector Financial Analysis and Viability Action Plan: Key Findings & Recommendations", May 18, 2016; ADB, "Report and Recommendation of the President to the Board of Directors: Proposed Loan Republic of the Union of Myanmar: Power Transmission Improvement Project (RRP MYA 46390-002), October 2015; Kee-Yung Nam, Maria Rowena Cham, and Paulo Rodelio Halili, “Power Sector Development in Myanmar”, ADB Economics Working Paper Series No. 460, ADB, October 2015; World Bank, "International Development Association Project Appraisal Document on a Proposed Credit in the Amount of SDR 286.9 Million (US$400 Million Equivalent) to the Republic of the Union of Myanmar for National Electrification Project", August 25, 2015

13 Kee-Yung Nam, Maria Rowena Cham, and Paulo Rodelio Halili, p.18-19



the Ministry, which reaches up to 1,669 billion kyat in 2015/2016.

Table 14.5-1 Budget to State Owned Economic Organizations under MOEP (Unit: Mil. kyat)

Source: Union Budget Law, 2015 (The Pyidaungsu Hluttaw Law No. 20, 2015), 9 April, 2015

Another example of the heavy dependence on the GOM’s subsidy is the increasing trend of the liability to the GOM. The balance sheet of MEPE proves this trend. There is the item of liability to the GOM as “Government Account: Operating Investment”.14 As the table shows, there is an increasing trend of the liability to the GOM in the past six years.

Table 14.5-2 Trend of Liability to the GOM of MEPE (Unit/ Million Kyat)

2009 2010 2011 2012 2013 2014

Amount 149,454 447,601 564,987 634,673 831,163 1,076,587

% of year to year change 199.5% 26.2% 12.3% 31.0% 29.5%

Source: MEPE, Statistics, 2014

Furthermore, the situation of 1) the tariff below the cost and 2) the dependence on subsidy is likely to continue to exist in the foreseeable future. As the forecast shows, the tariffs are expected to continue to be below the cost, though the gap between the cost and the tariff becomes narrow and the amount of subsidy is likely to decrease.

The subsidy is a significant burden to the GOM. The forecast expects that the subsidy is likely to reach 3.4% of the GOM budget in FY2017.

Though the forecast is prepared based on the various assumptions and the actual result of the forecast depends on the changes in the assumptions, there is a significant risk that the sustainable operation of the power sector depends on the steady allocation of the subsidy from the GOM unless the tariff increases to the level enough to cover the necessary cost and allow the room for profit.15

Previous Electricity Law (1984) did not provide concrete procedure and principles for determining tariff on generation, transmission, and distribution. 16 However, the new Electricity Law (Pyidaungsu Hluttaw Law no. 44/2014) defines “to write and promulgate equitable, transparent and reasonable rules and regulations for fixing electric power rates depending on the area” as one of the objectives of the Law.

14 There is also another item in liability, “Government Account: Initial Investment” in the MEPE’s balance sheet. This seems to indicate the

amount of the investment on the project by the government. 15 World Bank’s report points out that the potential financial loss without tariff increase and/or provision of subsidy is one of the financial risks. See “Annex 6: Financial Situation of the Power Sector” in "International Development Association Project Appraisal Document on a Proposed Credit in the Amount of SDR 92.6 Million (US$400 Million Equivalent) to the Republic of the Union of Myanmar for an Electric Power Project", August 29, 2013. 16 VDB Loi Co., Ltd, “The Legal and Regulatory Framework of Foreign Investment in Myanmar’s Power Sector: Analysis and Opportunities

for Reform ”, 8.1 Tariff setting, Chapter 8: Fiscal Structure, 25 April 2014

Currentexpenditure

Payment ofinterest Contribution Capital

ExpenditureDisbursementof loans

Repayment ofloans

Investment inorganizations Savings Total

expenditures

Working capital forcarrying out theirfunctions with theirown fund

Total

2015/16 136,956 0 0 471,798 0 26,407 0 0 635,161 1,669,975 2,305,136

Debts



With the approval of the GOM, the relevant ministry has the right to determine the tariff. In addition, the Electricity Regulatory Commission is regulated to be established. One of its functions is to advise with regard to the setting of electricity tariff. The enforcement of the tariff determination based on the new Electricity Law has yet to be seen.17

17 In reality, supplementary regulation is required to describe the detail of procedure, standard and other issues for tariff determination.

Chapter 15 Final Report Project Evaluation


CHAPTER 15

PROJECT EVALUATION



Chapter 15 Project Evaluation

Project Effect

15.1.1 Operation and Effect Indicators

Operation indicators are intended to evaluate the operational condition of the Project, which quantitatively checks whether the Project is being operated properly.

Table 15.1-1 Operation Indicators (Baluchaung No. 1 HPP)

Indicator Formula Benchmark Target

Unplanned outage hours Hours/Year 40:01 0

Capacity factor Net electric energy / (maximum output × hours per year) × 100 (%) 64% 81%

Source: JICA Survey Team, EPGE

Table 15.1-2 Operation Indicators (Sedawgyi HPP)

Indicator Formula Benchmark Target

Unplanned outage hours Hours/Year 275:11 0

Capacity factor Net electric energy / (maximum output × hours per year) × 100 (%) 56% 64%

Source: JICA Survey Team, EPGE

Effect indicators are intended to evaluate the outcome of the Project.

Table 15.1-3 Effect Indicators (Baluchaung No. 1 HPP)

Indicator Formula Benchmark Target Net electric energy production (GWh) As shown by the name of the indicator 156.782 200

Maximum output (MW) As shown by the name of the indicator 28.0 28.0 Source: JICA Survey Team, EPGE

Table 15.1-4 Effect Indicators (Sedawgyi HPP)

Indicator Formula Benchmark Target Net electric energy production (GWh) As shown by the name of the indicator 116.879 135

Maximum output (MW) As shown by the name of the indicator 24.0 25.0 Source: JICA Survey Team, EPGE

Chapter 15 Project Evaluation Final Report


15.1.2 Qualitative Impact of the Project

(1) As explained in detail in Chapter 14, the Project makes it possible for the people in the country to save the cost by replacing the expensive alternative energy source with the incremental supply of the grid electricity.

(2) In addition, the incremental electricity supply contributes to meeting the demand of electricity in the agricultural, commercial and industrial sectors and enhancing the economic activities in these sectors. The growth of economic activities is likely to lead to more employment and higher income in the long run.

(3) Residential consumers will be able to use more electric appliances and improve the quality of life. Children can study for longer hours at night under better lighting. Some of the residential consumers may be able to start or expand income generating activities at night by utilizing electricity. People can obtain the knowledge outside their world from television, radio and the internet.1

1 These advantages of more electricity supply are supported by the findings of the social impact assessment survey. See, para. 22, Annex 5:

Poverty and Social Impact Assessment in World Bank, "International Development Association Project Appraisal Document on a Proposed Credit in the Amount of SDR 286.9 Million (US$400 Million Equivalent) to the Republic of the Union of Myanmar for National Electrification Project", August 25, 2015



Reduction of GHG Emission

One of the benefits of the Rehabilitation Project is to expect reduction effect of GHG (greenhouse gas). In case rehabilitation works of existing aged hydropower plants are carried out, the incremental energy generation production is calculated as the difference between with-project and without-project.

The same values applied in the financial analysis are used for the incremental energy generation production corresponding to CO2 reduction.

Therefore, CO2 that is to be emitted in relation to the energy generation production is the reduction of CO2 emission due to the Rehabilitation Project.

Annual average generation production is calculated in case with-project and without-project from 2017 to 2036 for 20 years and annual incremental generation production is estimated as shown in Table 15.2-1.

In 2022, preceding Units of Baluchaung No.1 and Sedawgyi HPPs will start operation and following Units of both HPPs will start operation in 2023. Penstock gates of Sedawgyi dam will be rehabilitated in 2024 for gate No.1 and in 2025 for gate No.2. In case that Rehabilitation Project will not be implemented, Sedawgyi HPP would not be able to generate in 2030 and Baluchaung No.1 HPP in 2033.

CO2 emission factor for the electric system of Myanmar is 0.256 t-CO2/MWh, which is the average between 2008 and 2010 shown in Reference.

Table 15.2-1 Incremental Generation Production between With-project and Without-project (Unit: GWh)

Year a) With project b) Without project c) Incremental

generation (a-b)

Remarks Baluchaung No.1 HPP

Sedawgyi HPP

Baluchaung No.1 HPP

Sedawgyi HPP

Year 1 2017 157 117 157 117 0 Year 2 2018 150 112 150 112 0 Year 3 2019 144 106 144 106 0 Year 4 2020 137 101 137 101 0 Year 5 2021 90 56 130 96 -80 Year 6 2022 127 78 124 91 -9 Start generation of preceding units Year 7 2023 192 87 117 85 77 Start generation of following units

Year 8 2024 200 87 110 80 97 Rehabilitation of penstock gate No.1 of Sedawgyi dam

Year 9 2025 200 128 103 75 150 Rehabilitation of penstock gate No.2 of Sedawgyi dam

Year 10 2026 200 135 97 69 169 Year 11 2027 200 135 90 64 181 Year 12 2028 200 135 83 59 193 Year 13 2029 200 135 77 53 205 Year 14 2030 200 135 70 0 265

In case rehabilitation Project will not be implemented, Sedawgyi HPP would not be able to generate in 2030 and Baluchaung No.1 HPP in 2033

Year 15 2031 200 135 63 0 272 Year 16 2032 200 135 57 0 279 Year 17 2033 200 135 0 0 335 Year 18 2034 200 135 0 0 335 Year 19 2035 200 135 0 0 335 Year 20 2036 200 135 0 0 335




Using this factor, the reduction of CO2 emission by the Rehabilitation Project was calculated to be 49,408 t-CO2 emission per year in 2028, 5 years after completion of both HPPs and 85,760 t-CO2 emission per year in 2033, 10 years after completion of both HPPs as shown in the table below.

Table 15.2-2 Reduction of CO2 Emission by the Rehabilitation Project

year Incremental generation MWh/y

CO2 emission t-CO2/y Remarks

2028 193,000 49,408 5 years after completion of

both HPPs

2033 335,000 85,760 10 years after completion of

both HPPs Source: Prepared by JICA Survey Team



Table 15.2-3 Reduction of CO2 Emission by the Project (as of 2028)



Table 15.2-4 Reduction of CO2 Emission by the Project (as of 2033)



Reference: CO2 Emission Factors for Grid Electricity (Average of whole power source)

(Unit: g-CO2/kWh)

Source: CO2 EMISSION FROM FUEL COMBUSTION Highlights (2012 Edition), IEA, p.111~p.113)

JICA Climate – FIT Climate Finance Impact Tool for Mitigation, Ver. 2.0 March, 2014

Japan International Corporation Agency (prepared by Japan Weather Association)