ESD design guide for Australian Government buildings: Edition 2

esd opportunities in building
OPPORTUNITY 4
minimising energy use
Figure 23. Photovoltaic curtain wall, image
sourced from Doncaster Hill Sustainability
Guidelines, Manningham City Council.
Figure 24. Integrated amorphous
photovoltaic tiles, image sourced from
Doncaster Hill Sustainability Guidelines,
Manningham City Council.
(i.e. for photocopiers, computers,
etc.) is one method to minimise
operational energy use. This guide
does not provide detailed advice in
this area, but an effective purchasing
policy, energy saving settings and
periodic review of equipment settings
(people often turn efficiency settings
off when they don’t understand their
function) are initiatives to consider. For
more information see the DEH Green
Office Guide and DEH’s voluntary
environmental purchasing tools (refer
to online resources).
RENEWABLE ENERGY
Green Power, Solar Hot Water and
Photovoltaic systems
One main technique for minimising
the greenhouse intensity of the energy
used in a building is to use green
power (electricity which comes from
wind, water or solar sources) and/or to
use a cogeneration system.
Using solar energy for the provision
of hot water is another method for
using renewable energy and reducing
the greenhouse impact of a building.
Solar hot water systems involve
pumping water through pipes that
are laid on an absorber plate. Both of
those are coated with heat absorbing
material. The pipes and plate are
mounted in the sun’s direction to
maximise heat absorbance. The water
absorbs heat and transfers this heat
to a storage tank where it is collected
and ready for use when required.
A photovoltaic system (PV) uses
solar energy to generate electricity.
PV panels are made with a positive
and a negative layer of silicon. When
light falls on these layers, it produces
a potential difference (photovoltage)
between the layers by causing
electrons within the layers to move.
If an external circuit is present, this
voltage can drive a current through it.
This current is then converted to AC
current (the type of current used in the
office) via an inverter. This can then
power normal office appliances and
lights. If the office is connected to the
mains electricity, excess energy can
be redirected to the grid and the meter
turned backwards.
EMBODIED ENERGY
MINIMISATION
Embodied energy is discussed in
opportunity 7 choosing materials.
26 SEAV (2005) Personal Conversation Sustainable
Energy Authority Victoria 9/3/2005.
27 Crawford R.H. and Treloar G.J. (2004) Net energy
analysis of solar and conventional domestic
hot water systems in Melbourne, Australia Solar
Energy, vol. 76 (1-3), January-March 2004, pp.
159-163.
28 Going Solar 2005, Conversation 9/03/05.
29 E. A. Alsema and E. Nieuwlaar Energy viability of
photovoltaic systems Energy Policy, Volume 28,
Issue 14, November 2000, Pages 999-1010.
Effectiveness of
hot water and PV systems
Domestic hot water
cost payback: 6-7 years 26
embodied energy
payback: 0.5-2 yrs 27
Domestic and commercial
photovoltaic systems
cost payback: Greater than 10
years 28
embodied energy
payback: 2.5-3 yrs 29
Online Resources
Passive Design Techniques
Square One
www.squ1.com
Sustainable Building Sourcebook
www.greenbuilder.com/sourcebook/
PassiveSol
Renewable Energy
Greenpower
www.greenpower.com.au/
Solar Power
ATA (Alternative Technology
Association)
www.ata.org.au/
National Renewable Energy
Laboratory
www.nrel.gov/solar/
Energy Efficient Fittings & Equipment
Australian Greenhouse Office
Toolkit for local Government
www.greenhouse.gov.au/lgmodules
Department of the Environment and
Heritage
Environmental Purchasing Guide
www.deh.gov.au/settlements/government/
purchasing
Green Office Guide
www.deh.gov.au/settlements/government/
purchasing/pubs/
ESD DESIGN GUIDE FOR AUSTRALIAN GOVERNMENT BUILDINGS 023