week 3 gb course

Energy use in BuildingsWeek 3

Where are we?

Understanding Energy“The ability to do work”

Energy

Measured in Joules (J)

Power

Measured in Watts (W)= 1 J/sec

>>kWh

Understanding EnergyExample: kWh/day/person

UK

US

Austr

alia

China

Singa

...

Thaila

ndIn

dia

Vietn

am0

50

100

150

200

250

300

108.42

239.00

194.47

50.91

122.96

51.6717.22 21.14

Energy use (kWh/day/person)

kW

h/d

ay/p

ers

on

Understanding EnergyExample: Honda Wave 120km

Vietnam average energy consumption = 21.42kWh/pp

Your ecological footprint

http://myfootprint.org/

Energy consumption through Buildings >> ELECTRICITY

When designing a green building, how do we know how much electricity our buildings will actually save?

Energy consumption through Buildings >> ELECTRICITY

How do we know how much electricity our buildings will save?

Energy Model:- Comparison with a Baseline Model- Comparison with a Benchmark

Electricity consumptionJohor Bahru Case Study, Residential House

*Kubota, Tetsu et al, "Energy Consumption and Air-Conditioning Usage in Residential Building of Malaysia”, 2011

*Kubota, Tetsu et al, "Energy Consumption and Air-Conditioning Usage in Residential Building of Malaysia”, 2011

Electricity consumptionHong Kong Data, Residential

*Hoang Kong Energy End Use Data Report 2012, The Energy Efficiency office

Electricity consumptionHong Kong Data, Office

Electricity consumptionHong Kong Data, All buildings + Transport

*Hoang Kong Energy End Use Data Report 2012, The Energy Efficiency office

Electricity consumptionHong Kong Data, Renewable Energy

*Hoang Kong Energy End Use Data Report 2012, The Energy Efficiency office

Electricity consumptionHong Kong Data, Renewable Energy

*Hoang Kong Energy End Use Data Report 2012, The Energy Efficiency office

Renewable Energy

What types of Renewable energy are available?

Solar – Photovoltaics, Solar Hot Water

Transparent Photovoltaics, CSIRO Energy Centre, Newcastle Australia

Solar – Photovoltaics

- Building Integrated Photovoltaics (BIPV)

- Big C Green Square PV cells on carpark shade structure & roof

- Green One UN House will produce >17% of its own electricity

Photovoltaic Cells Cost and other Considerations- Crystalline silicon solar cell prices have

fallen from $76.67/Watt in 1977 to an estimated $0.74/Watt in 2013 (Swanson’s Law prices fall 20% for every doubling of production capacity)

- As of 2011 the cost of PV has fallen below Nuclear Power

- Current developments achieving efficiency of 44%, commercially available cells are 14-22% efficient

Solar – Concentrated Solar (Thermal) Power

Spain CSIRO Energy Research Centre, Newcastle AU

Solar Hot Water

Solar Hot Water- Can easily supply

domestic hot water needs in houses in Southern Vietnam

- Northern Vietnam may need to use higher capacity system to compensate for days without much sun * 2011 Edition Handbook for Green Housing

Wind Power

Large scale wind farming High Altitude Wind

Wind Turbines integrated in buildings?

147m tall Strata Building, LondonOffsets 8% of power in building (equivalent to mechanical and electrical services)

Wind Turbines integrated in buildings?

240m tall Bahrain World Trade Centre11-15% of power generated by wind turbines

Wind Turbines integrated in buildings?

309m tall Pearl River Tower, Guangzhou, China (SOM 2011)Combined with PV the renewable energy generated is <10% of building energy needsWind turbines are a powerful green symboll

Hydropower?

Tidal or wave power?

Biomass? Biofuel? Geothermal?

CogenerationHeat Recovery

Air Conditioning- Coefficient of Performance (COP)

* LOTUS NR V1.1

Air Conditioning- Window and through wall system

Air Conditioning- Split System

Air Conditioning- VRF (Variable Refrigerant Flow)

Air Conditioning- Chilled Beam (passive/active) & Chilled Slab- >>Not good for tropical or humid climates

Lighting

BUT…it doesn’t matter how efficient you are

It also comes down to the occupants, maintenance, controllability, automatability and the design of the space

What are some factors that could be more important than the efficiency of systems and equipment?

BUT…it doesn’t matter how efficient you are

Consider (AC):- Floor area- Air Leakage - Individual thermal controls- Zoning- Set points (thermostat)- Cleaning of filters - Maintenance- Building Automated System- Thermal comfort

BUT…it doesn’t matter how efficient you are

Consider (Lighting):- Size of space- Daylighting- Lighting level- Task lighting - User controllability- Timer lighting- Sensor lighting- Automated lighting- Switch zones- Hours of operation