Comprehensive Design & Implementation Approach of Solar Power System … · 2019-11-15 · Comprehensive Design & Implementation Approach of Solar Power System in Subtropical Hong

Comprehensive Design & Implementation Approach of

Solar Power System in Subtropical Hong Kong

Ir Dr Tony Lam

Associate Director of ArupCEng, CPEng, MHKIE, WELL Faculty, LEED AP, BEAM Pro ND NB

13 December 2018

CIBSE One-day Seminar on Renewable Energy New Development and Technologies in Hong Kong

• Context and Role of solar power system

• Approach of designing a solar power system

• Post-installation evaluation

Agenda

Climate change is real!

The “Hong Kong's Climate Action Plan

2030+” report, published by the

Environment Bureau on January 2017

Context and Role of Solar energy system

Solar power system can:• To achieve the goals of

carbon emissions• To respond government

policies


Source: www.climatereadt.gov.hkCarbon Footprint of Hong Kong


World Green Building Council – The Net Zero Carbon Buildings Commitment

• 2030 – to reach net zero carbon operating emissions within their portfolios

• 2050 – to advocate for all buildings to be net zero carbon in operation


25% PV

coverage of

HK land

100% LNG

+ 15% PV

coverage

50% better BEC for

all bldgs

+ 15% PV coverage

70% LNG

+ 10% PV coverage

+ 50% better BEC for all bldgs

+ 50% GV Bus

1 2 3

How to make Hong Kong Net Zero Carbon?

Proposed Solutions:

Existing Condition:

PV LNG Efficient

BuildingGreen

TransportationHong Kong climate Action Plan 2030+

4


25% PV

coverage of

HK land

100% LNG

+ 15% PV

coverage

50% better BEC for

all bldgs

+ 15% PV coverage

70% LNG

+ 10% PV coverage

+ 50% better BEC for all bldgs

+ 50% GV Bus

1 2 3

How to make Hong Kong Net Zero Carbon?

Proposed Solutions:

Existing Condition:

PV LNG Efficient

BuildingGreen

TransportationHong Kong climate Action Plan 2030+

4

Solar PV System plays a

KEY ROLE

Building:• Zero/Low Carbon Design Steps• Sub-tropical Climate• Architectural Design• Energy Efficient System• Renewable Energy

Context and Role of Solar energy systemDrivers

Avoid energy use

Use energy efficiently

Decarbonize


Korea Zero Energy House:• Year 2010• Resort House• 425 m2 floor area• 163 m2 rooftop PV• PV 44% contribution of total energy


Singapore Zero Energy Building:• Building and Construction Authority

(BCA)• Office Building• 4,500 m2 floor area• 1,540 m2 rooftop PV


HK Zero Carbon Building:• Year 2012• Construction Industry Council (CIC)• Exhibition/Office Building• 1,520 m2 floor area• 1,015 m2 rooftop PV

Regulations/Incentives:• To take advantage of Feed-in Tariff• Effective date:

• CLP – October 2018

• HEC – Jan 2019

• Commitment period: 15 years• FiT rate for solar energy:

• Under 10kW – HKD5 per kWh

• 10kW to 200kW– HKD4 per kWh

• 200kW to 1MW– HKD3 per kWh


Approach of designing a solar power system

Approach of designing a solar power system

Scale fits the demand?

Fixing and Safety?

Electrical connection Safety?

Affect surroundings?

Step 1: Building and Location Analysis• Architectural layout plan study• Site visit• Propose potential location

Step 2: Solar Resource Assessment• Solar resource simulation• Shading and glare analysis• Identify orientation and inclination of

PV panel

6 Steps in Designing a PV System

1. Building and Location

Analysis

2. Solar Resource

Assessment

3. Selection of Solar

Technology

4. PV System Design

5. Structural Aspect

Assessment

6. Statutory Submission

and Approval


Step 3: Selection of Solar Technology• Conventional Photovoltaic (PV)• Thin-Film Solar Cells (TFSC)• Building Integrated PV• Hybrid PV (PV + Thermal)

Step 4: PV System Design• PV Schematic System Design• Metering Design• Plantroom Design• Other Issues for Implantation of

Existing Building


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval


Step 6: Statutory Submission and Approval• Application of CLP/ HKE for Feed-in

Tariff (FiT)• Submission and Approval for Building

Department • Issuance of Work Completion Certificate

(WR1)

Step 5: Structural Aspect Assessment• Dead load and live load assessment• Propose installation method


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval

Steps 1 & 2

Building 3D model with

topography and surrounding

buildings

Annual solar availability

Annual glare study

Optimization of PV orientation and tilt angle


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval

3D Building Modelling with Surroundings

• Surrounding buildings/ self shading/ topography

• Request GIS information from Lands Department

http://www.hkmapservice.gov.hk/OneStopSystem/map-search?product=OSSCatB&series=iB1000

3D Building Modelling with Surroundings

• Topography, Building massing andBuilding height variations are modelled

• Together with the proposed buildingmassing and PV panel layout, this formthe foundation of later studies.

• Surrounding model by 3D modellingsoftware

Annual Solar AvailabilityPrescriptive Approach

• Solar chart to determine the preliminary PV panel orientation and tilt angle

• Data measurement results show that the optimal setting is around 20-23deg tilted due south orientation

• Use performance approach to determine the preliminary location of PV panel

Annual total solar yield (kWh/m2) for various tilt angles and orientations in Hong Kong

Source: Tony Lam’s PhD Thesis 2008

Annual Solar AvailabilityPerformance Approach

Shading above

High

Mid

Low

• With self shading/ surrounding buildings shading effect,

• Annual solar availability

Recommended PV installation area

Annual Glare Study

Annual Glare Study

• Geometric analysis based on Hong Kong solar path

• It is not SIMPLE!

Site Building

Sensitive Receivers

Surrounding Buildings

• Reflection from PV panels may result inundesirable glare for pedestrian,occupants of neighboring buildings

• Sensitive receivers include:➢ Office➢ Residential➢ School➢ Hotel➢ Hospitals➢ Shopping Centre➢ Shops➢ Air flight path➢ Etc.

Annual Glare Study

Annual Glare Study

• Geometric analysis based on Hong Kong solar path in Grasshopper software

• Glare study is carried out from 7am to 6pm throughout the whole year

• Visual the potential glare problem for sensitive receivers

PV Panel Scale Design• After knowing the basic information such as solar availability variation, glare issue, PV orientation and tilt angle,

the next step is to determine the PV panel scale

• PV panel scale depends on➢ Site constraint (space)

➢ Energy saving target (green building certification requirement)➢ FiT Scheme (Incentive)➢ E&M limitation (for existing building)

PV Panel Scale Design• Determine the whole building energy consumption• By Energy Modelling• Increase the % of renewable energy contribution

MAXIMIZE ENERGY GENERATION % BY PV


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval

Type of PV Technology• Mono- and Poly-crystalline• Thin-Film Solar Cells (TFSC)• Hybrid PV (PV + Thermal)

Building Integrated PV

Mono-crystalline PV

Job reference: Zero Carbon Building

Selection of PV Technology

Design consideration:• Performance at ambient temperature• Module efficiency• Space requirement

Conventional PV


Monocrystalline Silicon Solar Cells• Power range: 290-365W• Efficiency : 15-23%• Dimensions:

1600mm(L)x1000mm(W)x50mm(H)

• Weight: 18~19kg (~12kg/m2)

Polycrystalline Silicon Solar Cells• Power range: 250-270W• Efficiency : 13-16%• Dimensions:

1600mm(L)x1000mm(W)x50mm(H)

• Weight: 18~19kg (~12kg/m2)

Walkable PV panel at floor Application:PV panel at traditional roof, flat surface

For Example:PV at rooftop, PV wall mounted at building façade, PV at floor

PV panel at rooftop

Thin-Film Solar Cells (TFSC)

• Categorized by which photovoltaic material

➢ Amorphous silicon (a-Si)

➢ Cadmium telluride (CdTe)

➢ Copper indium gallium selenide (CIS/CIGS)


Thin-film CIGS solar cells• Power range: 70W-310W• Efficiency : 10-16%• Dimensions:

1700/2590/5900mm(L)x350mm(W)x2.5mm(D) • Flexible Weight: <2.4kg/m² (less structural requirement)

Application:PV at curved surface, structures, low load capacity roofs, building integrated PV module

For Example:PV at curved rooftop surface

Building Integrated PV (BiPV)

• Thick crystal products

➢ Solar cells by crystalline silicon (150x150 mm2)

➢ Deliver 10-12 watts per ft² of PV array

• Thin-film products

➢ Thin layers of photovoltaicly active material placed on a glass superstrate or a metal substrate

➢ Deliver 4-5 watts per ft² of PV array area

Application:PV panel integrated in building materials

For Example:Solar paving block at pavement, BiPV Skylight, BiPVGlazing

Solar Paving Block

Photovoltaics in glazing


Photovoltaics in glazing

Hybrid PV and Thermal (PVT)

• Increase electricity output performance by around 10%

• Backside of the panel is composed of a heat exchanger. The water that circulates through the exchanger is warmed by the heat dissipated from the photovoltaic cells and can reach temperatures up to 70°C

• Reuse the heated water in different ways

• Space saving

Application:Building with hot water demandFor example:Commercial building, hotel, hospital , clubhouse, etc…

Power out

Hot waterout

Cold waterin



Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval

PV Schematic System Design

Power Distribution

Board

CLP / HKE Meter

Electrical Equipment

Inverter

PV System Design

$

Sale to Power Company

Transformer

Feed-in Tariff Metering Requirement for CLP

• Simplified Single-Line Electrical Diagram for FiT Meter Arrangement for a RE System

PV System Design

Feed-in Tariff Metering Requirement for CLP

PV System Design

PV System Design

Feed-in Tariff Metering Requirement for HKE

• Simplified Single-Line Electrical Diagram for FiT Meter Arrangement for a RE System

PV System Design

Feed-in Tariff Metering Requirement for HKE


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval

Structural/ Roofing Design Issue

Concrete Building Roof Sheet Metal Roofing Structure

• Roof made by solid concrete• Withstand higher loading• Less strengthening required• Flat roof surface

• Roof made by sheet metal• Withstand lower loading• More strengthening by roof truss steel members• Corrugated shape with inclined angle


• Types of roofing system – Concrete Building Roof

Concrete plinth

Solar panelMetal frame


Direct Screw Fixing Type Standing Seam Type

• Types of roofing system – Sheet metal Roof Structure➢ Direct Screw Fixing Type (Corrugated Metal Roof)➢ Standing Seam Type


• Strategy of installation ➢ Screw Fixing(punch through) for Direct Screw Fixing Roofing system➢ Proprietary Add-on Clamp for Standing Seam Roofing System

Direct Screw Fixing Type Standing Seam Type

Waterproofing – Screw Fixing vs Add-on Clamp


• Sample of PV panels installation for Standing Seam Roofing System


• Other Issues➢ Dead load on PV panels and supporting frame

➢ Wind load on PV panels

➢ Waterproofing – Screw Fixing vs Add-on Clamp

➢ Testing of the Special Add-on Clamp (BD requirement)

➢ Warranty – Warranty Period and Validity of Warranty (for existing building)


Analysis

2. Solar Resource

Assessment


Technology

4. PV System Design


Assessment


and Approval

Application of Feed-in Tariff (FiT) to CLP/ HKE

Submit application and required documents

Technical assessment, system test and installation before CLP smart meter installation

Completion and grid connection

Application Process for CLP

Application Process for HKE

Statutory Submission and Approval

New building• General Building Plan submission

Existing Building• Minor Works Submission (Class I or III)

• For Class I item 1.19

➢ Step 1 - Appoint Prescribed Buildings Professional and Prescribed Registered Contractor (Class I of Type A, E)

➢ Step 2 - Submit MW01 - Notice of Commencement, documents, photos 7 days before commencement of work

➢ Step 3 - Submit MW02 - Certificate of Completion, documents, photos within 14 days after completion of work


Submission and Approval for Building Department

Existing Building

• For Class III item 3.15

Step 1 - Appoint Prescribed Buildings Professional and Prescribed Registered Contractor (Class III of Type A, E)

Step 2 - Submit MW05 - Notice and Certificate of Completion, documents, photos within 14 days after completion of work


Submission and Approval for Building Department


Issuance of Work Completion Certificate (WR1)

Completion of Electrical Work

Electrical Inspection

Issuance of Work Completion Certification(WR1)

Power Energization

Post-installation Evaluation & Optimization

Conventional PV System Performance monitoring• Data analysis by comparing energy data

monitored by PV inverter and microclimate station

Microclimate Station

BMS System

InverterPower

DistributionBox

CLP / HKE Meter

Data Analysis


Transformer $

Dashboard

Solar Radiation

Data

• Using power optimizer to maximum energy yield• Carry out maximum power point tracking (MPPT) at module level

Traditional String Inverter• Suit for roof where ideal for solar • Simple and most affordable• MPPT per string • Power losses due to module mismatch• Weak panel and faulty panel is not easy to be

identified

Power Optimizer plus Inverter• Suit for roof have shading• Higher cost• MPPT per PV module• More equipment means more effort on

maintenance and replacement• Power monitored from each module individually


Operation concept of power optimizer


Under ideal condition Under partial shading condition

inverter inverter

Source: xx

Advanced PV System Performance monitoring• Data monitored by power optimizer

BMS System

InverterPower

DistributionBox

CLP / HKE Meter

Data Analysis

Power Optimizer

Power Optimizer


Transformer $

Manufacturer cloud

Microclimate Station

Solar Radiation

Data

Solar Power System

• Reduce the building electricity demand

• Optimised Solar PV System• RE Output target• Scale optimization• Disturbance of surroundings• Structural loading• Electrical connection• Financial model

• Monitoring and Maintain Performance

Source: CCC Kei Wai Primary School Ma Wan

Demonstration + Make it as common practices!

Thank You!

Ir Dr. Tony Lam

Associate Director of ArupCEng, CPEng, MHKIE, WELL Faculty, LEED AP, BEAM Pro ND NB

13 December 2018

CIBSE One-day Seminar on Renewable Energy New Development and Technologies in Hong Kong

Documents

Comprehensive Design & Implementation Approach of Solar Power System … · 2019-11-15 · Comprehensive Design & Implementation Approach of Solar Power System in Subtropical Hong