2011.10 - BLC NSE Solution Proposal

7/31/2019 2011.10 - BLC NSE Solution Proposal

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SolutionDescriptionSite:BuffaloLuxuryCampDate: October 2011

Preparedfor:Buffalo Luxury Camp, Tanzania Serengeti Camp.

Preparedby:New Southern Energy

Company:Unique Safaris, US office


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2011.10 Buffalo Luxury Camp Solution Proposal Page | 2

Executive Summary

New Southern Energy (NSE) conducted a site assessment at Buffalo Luxury Camp on19 September 2011. This proposal is based on information gathered during this site visitand discussions with the camps management.

Most of the camps power is used by the guest rooms, common areas and operationalareas. Heating water is the largest component of energy usage in these areas.The camps generator uses 1,547 litres of diesel per month on average (based on past12 months). The camps occupancy level is 7% over this period. The highest occupancy

over the past 12 months is during July 2011. The camp reached 27% occupancy duringthis month and the generator used 2,730 litres of diesel.There is a strong positive correlation between occupancy and diesel usage.Since occupancy is low currently and the camp management expect occupancy to increase,the solutions recommended are the first step in a phased-in approach.The solution we recommend is designed to improve efficiency by using two industrial sizedsolar ringmain system to heat water. This system is more efficient than individual geysers.Individual solar geysers are recommended for the staff village.

A hybrid PV solar and battery solution is recommended to provide additional powerrequirements and reduce generator runtime.The total cost of the solution is $ 210,625.50 Ex Vat (based on exchange rate of $1 = R8). The solution provides more hot water than is currently available. Hot water is alsoprovided to the staff village, which doesnt have hot water currently. The camps availablepower is increased to 24 hours through 17 kW of PV Solar and 48 x 2V 1,600 Ahr batteries.At an average of7% occupancy, generator runtime will be reduced to at most one hour

per day. The financial benefits of this would be an IRR of 11% and a simple paybackperiod of 6 years.At an average 27% occupancy, generator runtime will be reduced to 2-3 hours per day.

The financial benefits of this would be an IRR of 19% and a simple payback period of4-5years.The PV system is hybridised and is triple redundant. Power is first provided by the PVsolar panels. When there is no sun, the batteries provide the camp with power. In the event

that the PV solar and batteries cannot meet the camps requirements, the generator will becalled on. The generator will be run optimally (load draw and runtime) to improve fuelefficiency and generator performance.When needed, additional PV solar panels, inverters and batteries can be easily incorporated

into the above system.

Objectives

Provide the best hot water solution for the camp taking cognisance of the environment,operational requirements, guest experience, staff capabilities and management expectation.

A renewable energy solution is used.Provide camp with access to power for 24 hours, and reduce generator runtime. Arenewable solution is used.Solutions must be modular to easily increase system size if required.System is robust and requires minimal maintenance.


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System design process

During the NSE site visit, the following information was gathered.

1. Inventory count for camp, usage pattern and site layout2. Load profile and daily kWh usage (from smart-meter)3. Diesel usage, associated costs and guest occupancy4. Operational timetable for staff and guests5. Management discussion understanding camp requirements

Figure 1 Estimated usage by area of camp (at 27% occupancy)

Figure 2 Diesel usage and Camp occupancy per month

NSE installed a smart-meter on the generator to measure actual usage. The information is not yetavailable due to lack of GSM signal and network connection. NSE will be able to access thisinformation once a network cable is installed. During the site visit, NSE managed to get three daysof actual consumption (kWh) and diesel usage. Using a conservative estimate of 0.32 litres per

kWh, NSE estimated that the camp uses approx. 160 kWh per day. This is consistent with dieselconsumption and occupancy over the past 12 months. The generator runs for 10 hours each day,which means an average draw of 16 kW. In reality, the actual draw peaks when most appliancesare on and then drops to a far lower level for most of the day. Should the camp have power for 24hours, we expect the average draw to be far lower than 16kW. Most usage happens during earlymorning and early evening. People shower before game drives. During the day, kitchen andlaundry use energy. Late evening, people generally shower after game drive or before shift

change.

Guest rooms

49%

Offices

6%

Manager house

8%

Common area

22%

Kitchen

7%

Laundry

8%

Estimated usage by area at 27% occupancy

MonthDiesel

litres

Cost/

litre ($/l)

Total

cost ($)

%

occupancy

Sep- 2010 1 400 1.38 1 932 4%

Oct-2010 1 400 1.38 1 932 5%

Nov- 2010 1 400 1.38 1 932 3%

Dec- 2010 1 400 1.38 1 932 1%

Jan- 2011 1 400 1.38 1 932 3%

Feb-2011 700 1.38 966 2%

Mar- 2011 1 120 1.38 1 546 14%

Apr-2011 280 1.38 386 0%

May- 2011 2 100 1.38 2 898 9%

Jun- 2011 1 680 1.38 2 318 3%

Jul- 2011 2 730 1.38 3 767 27%

Aug- 2011 2 030 1.38 2 801 12%

Sep- 2011 2 321 1.38 3 202 12%

Total 19 961 27 545

0%

5%

10%

15%

20%

25%

30%

-

500

1 000

1 500

2 000

2 500

3 000

Sep-2

010

Oct-2

010

Nov-2

010

Dec-2

010

Jan-2

011

Feb-2

011

Mar-2011

Apr-2011

May-2

011

Jun-2

011

Jul-2011

Aug-2

011

Sep-2

011

Occupancy

Diesellitres

Diesel consumption and Camp occupancy

Diesel litres % occupancy

The consumption by area iscalculated based on inventory count

done and assumed hours ofoperation per appliance. This isprovided by operational staff where

possible. NSE has madeassumptions where information isnot available.

Some areas will use the sameenergy irrespective of occupancylevels (e.g. offices, common areas).Other areas usage is directly linkedto occupancy.


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System design explanation

The solutions designed take the following into consideration:

Camp has access to power for 10 hours a day. The solution is designed to provide power

to the camp for 24 hours and reduce generator usage.Improve energy efficiency through use of best available technologies.

o Solar ringmain hot water system is far more efficient than multiple individualgeysers in this environment.

o Using high-quality LED lights will reduce camps load further (LED lights are notquoted in this proposal)

System can easily be increased at a later stage if camps energy requirements increasedue to higher occupancy levels or more appliances increasing consumption.Operating environment, conditions, staff capabilities and guest experience.

Solar hot water solutionBased on site assessment, energy to heat water is atleast half of the camps total consumption. An

industrial solar ringmain hot water solution will reduce reliance on the generator to heat water.Two ringmains are suggested to supply hot water for the lodges operations (kitchen, laundry) andguest rooms. A ringmain system is more efficient than individual geysers as the components arecentralised. Therefore, all hot water is available for use. Maintenance and system management is

simpler. Six individual solar geysers are recommended for the staff village. The hot waterrequirements of the staff village does not justify a ringmain system. The peak draw will be reducedconsiderably compared to electric geysers. The maximum draw is limited to size of elements in theheat pumps (1.2 kW per heatpump). There are four heatpumps in total and it is unlikely that all

four will run at the same time.

Each ringmain consists of the following (Figure 3 below shows overview):

1 x 2,000 litre thermal storage

9 x vacuum tubes (24-tube set)2 x heat pump (to provide for redundancy protection)Piping, lagging and other parts

Figure 3 Solar ringmain hot water solution overview


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PV solar and battery solutionOnce the camp is made more efficient (from solutions discussed above), a hybrid PV solar solutionwill be used to meet the camps energy requirements. This solution combines the use of PV solar,

batteries and the diesel generator to supply power to the camp. The solution is modular, whichmeans further PV solar, inverters and batteries can be added without replacing existinginfrastructure. The system is centralised and grid-tied, ensuring all solar energy generated is usedeither directly in the camp, or stored in the batteries for later use.

The system is designed to provide the camp with 24 hours of power per day (increased from 10hours currently). Under current occupancy levels (of 7% on average), the PV solar and batteries

will be able to provide more than 90% of the camps energy requirements. The system will consistof the following:

PV panels > 17 kW of PV solar which will produce 90 kWh per day on average.

Grid-tie inverter > 17 kW inverter to convert DC current from PV panels to AC foruse in lodge.

Sunny island inverter > 30 kW of inverter to transfer energy between batteries and camp.Batteries > 48 x 2V 1,600 Amp hour cells can deliver up to 100 kWh backup

power at night (or cloudy days).The figure below shows an overview of the PV system and components.

Figure 4 PV solar and battery system overview (Please see Annexure A for technicaldrawing)

At higher occupancy levels, the above system will provide less than 90% of the camps energyrequirements. At 27% occupancy, the above system will meet approx. 75% of the camps energyneeds. This means the generator will run for 2.5 hours per day on average.

The generator is used as a backup in the event the camps energy requirements is greater thanthat available from PV solar and batteries. The generator will be called on to provide the campwith the additional energy in this case. The generator will run at optimal levels (of 80% of load)

and excess power will be used to charge batteries. This will ensure generator runtime is minimized.


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System costing

The table below shows the costs in $ (ex vat). An exchange rate of R 8 = $ 1 is used. Below pricesare valid for 15 days due to volatile exchange rates.

Table 1 Costing of NSE solution ($ ex vat)Product Units Cost per unit

($)Total cost ($)

P

Vsolarandbattery

system

MC box 1 3,850.00 3,850.00

Sunny island 5kW 48V 6 4,900.00 29,400

Deep cycle lead acidbatteries

48 656.25 31,500.00

Sunny boy 17000TL inverter 1 7,787.50 7,787.50

PV panels (Watts) 17000 1.93 32,725.00

Cabling, fuses, parts 1 3,937.50 3,937.50

PV frame 1 5,162.50 5,162.50

Labour and installation 1 10,325.00 10,325.00

Delivery 1 11,250.00 11,250.00

Solarhot

water:lodge

operationsand

guestrooms

Geyser 2,000 litre storage 2 4,287.50 8,575.00

Heat exchanger 2 997.50 1,995.00

Vacuum tubes (24-tube set) 18 1,085.00 19,530.00

Heat pump (4.7kW output) 4 1,365.00 5,460.00

Piping lagging and parts 1 11,375.00 11,375.00

Labour and installation 1 6,125 6,125.00

Delivery 1 2,625.00 2,625.00

Solarhot

water:

staff

village

Geyser 200 litre 6 857.50 5,145.00Vacuum tubes (24-tube set) 6 1,085.00 6,510.00

Piping lagging and parts 1 2,187.50 2,187.50

Labour and installation 1 3,412.50 3,412.50

Delivery 1 1,750.00 1,750.00

Total 210,627.50

SuppliersNSE uses the best products in the solutions we provide. The products are made by reputablecompanies who have a long track record. These companies provide strong guarantees andwarranties, which NSE would pass on to Buffalo Luxury Camp.

Brand Why used by NSE?

Worlds No.1 manufacturer of crystalline silicon photovoltaic modules Rigorous quality control meeting highest international standards

(ISO 9001:2008 and ISO 14001: 2004) Warrants 6.7% more power than market standards over 25 years Largest and most reputable inverter company in the world Innovative leaders in this segment Exceptional and tested service Reliable products which work in extreme conditions Over 80 years experience producing batteries in South Africa Highest ratings (ISO 9001:2008;ISO 14001: 2004) SABS approved Advanced testing conducted in collaboration with CSIR and selected

universities

Rigorous metallurgical evaluation


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Products used in solution

Component Description

Vacuum tubes Vacuum (or evacuated) tubes absorb solar energy converting it into heatfor use in water heating. The outer tube is transparent allowing sun rays to

pass through with minimal reflection. The inner tube is coated with anumber of special selective coating which provides good solar radiation andminimal reflection properties. The top of both tubes are fused together andthe air between the two layers of glass is pumped out, while the tube isexposed to high temperatures. This evacuation of the gases forms avacuum, which is an important factor in the performance of the vacuumtubes. The pressure in the tubes is less than 5x10-3 pa. This can only be

done (and maintained) through a specialized evacuation process performedduring production. This vacuum eliminates conductive and convective heatloss.The heat is transferred through the manifold, which will need routinemaintenance to ensure it is working at peak performance.

Thermalstorage

This is a 2,000 litre storage tank ideally suited for industrial applications.Inner tank is manufactured from epoxy vinyl-ester resin and glass. Theouter casing is manufactured from UV stabilized gel coat and glass.Insulation is 70 mm thick and made from high density polyurethane. Thereis 32 mm of solid super wood between inner tank and outer casing.

The tank is made from a non-ferrous material.

The water in the thermal store is mixed with glycol to prevent freezing and

corrosion of the pipes and tanks. The water and glycol mixture iscontinuously maintained at a high temperature as it is circulated betweenthe thermal storage and the vacuum tube panels.

Heatexchange

This is the medium that transfers the absorbed heat to the water to be usedin the camp.

The water to be used in the camp is run through a separate pipe thatenters the thermal storage, goes through a copper coil heat exchange andcomes out of the thermal storage at the surrounding water temperature.The heat exchange has an effective power output of 119 kW.

Heat pump Heat pumps use the reverse cycle of a refrigeration plant to heat water.The system employs an evaporator, a compressor, a condenser, refrigerantgas and an expansion valve within a closed circuit. Latent heat is given off

when the refrigerant gas is liquefied through the condenser and transferredto the surrounding water. The heat pump has a COP of four, which meansfor every 1 kWh of electricity supplied to the heat pump, 4 kWh of thermalenergy, in the form of hot water is produced. The heat pump is used as a

backup only when the vacuum tubes are not providing the required thermalenergy to heat the water.

PEX piping PEX (or cross-linked polyethylene) is part of a water supply system. The

material is made from cross-linked (HDPE) high density polyethylenepolymer. The HDPE is melted and continuously extruded into the tube.

PEX plumbing has been in use in Europe since 1970s. The use of PEX pipinghas increased since then, replacing copper pipes in many applications,especially radiant heating systems. PEX piping can turn 90 degree cornerswithout the need for elbow fittings. Can also be installed without need of

coupling fittings.


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Component Description

PV Solarpanels

PV (Photovoltaic) Solar panels generate electrical power by using solar cellsto convert energy from the sun into electricity. The solar cells produce

direct current (DC) from sun light, which will be used to power equipment/appliances or to charge batteries.

Grid-tieinverter

A grid-tie inverter is a special type of inverter which converts direct current(DC) into alternating current (AC) and feeds this into the lodge (via theMulti-cluster box). The grid-tie inverter must synchronize its frequency withthat of the camp grid (e.g. 50 or 60 Hz) using a local oscillator and limit the

voltage to no higher than that of camps grid. The power factor is 1, whichmeans the inverter output voltage and current are perfectly lined-up and itsphase angle is within 1 degree of the camps grid. The inverter has an on-

board computer which will sense the AC waveform and output a voltage tocorrespond with the camps grid.

Grid-tie inverters are also designed to quickly disconnect from the grid

when the camps grid goes down. This is a safety precaution to ensure theenergy it produces does not harm any line worker sent to fix the campsgrid.

Sunny islandinverter

The sunny island inverter converts direct current (DC) from the battery intoalternating current (AC) for the camps grid. It also converts AC from the

camps grid to DC when charging the batteries.

Deep cycle

Battery

The batteries store power, which will be used by the camp when there is no

sun.

The architecture of the batteries consist of lead plates and an acidic solutionof SiO2 as electrolyte. The first few charge/ discharge causes theelectrolyte to solidify and form a non-toxic substance. This results in a safe,fluid-less, high performance and environmentally friendly battery.

Multi-clusterbox

Used for integrated AC distribution in the camp. This is the brain of thehybrid system and communicates with grid-tie inverters, sunny island

inverters, generator and the lodge.


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Financial benefits

There is good financial benefit from implementing the suggested solar hot water and hybrid PVsolar solutions. It is important to remember that the solutions will increase the camps poweravailability to 24 hours (from 10 hours), and at the same time reduce generator usage.

The financial benefit is shown under two scenarios:1. Forecasting the camps current usage vs. usage after NSE solution

(based on 7% occupancy)

2. Forecasting the camps current usage vs. usage after NSE solution(based on 27% occupancy)

The figure below summarises the forecasted usage and financial benefits. The additionalassumptions used are listed below the figure.

Figure 5 forecasted energy costs in $ (Current ave occupancy and 27% ave occupancy)

Assumptions:Diesel cost (including transport) of $1.38 in 2011. Diesel and generator servicing inflation of

8% per annumMajor service (and overhaul) cost of generator not included in current costs (not available)Replacement cost of existing appliances and parts not included in current costs. E.g. electric

geysers will need to be replaced every 5 years depending on water quality etc.Solar hot water system will improve camps energy efficiency by atleast 40% (prudentassumption)


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Annexure A Hybrid PV Solar system technical drawing

Documents

2011.10 - BLC NSE Solution Proposal