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Lifetime Affordable HousingCentre for Design, RMIT University
DesignBUILD Seminar Series Catalyst for change
Friday 25th June 2010 12.30-13.30 hrs
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Acknowledgements
Acknowledge the Traditional Custodians of the Land, of Elders past and present, on which this meeting takes place.
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Acknowledgements
Project is funded by the Australian Research Council Linkage Scheme
Project partners and other contributors.
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Lifetime Affordable Housing
Australian Research Council (ARC) funded linkage project, of 3 years duration – Nov 2007 start.
3 PhD scholars & 1 full time researcher Key research themes: 1.Costs, 2.Location, 3.Affordability, 4.Policy
implications
Project partners RMIT University UniSA Building Commission VicUrban Land Management Corporations (LMC) SA
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Background
To limit global warming to 2C IEA proposes a 450ppm scenario (IEA) – this means a reduction of emissions to 25% below 2000 levels by 2020
Australia’s emissions 2000 - 553 Mt CO2 2020 target - 470 Mt CO2
BAU trend Australia’s domestic emissions would be expected to be 692 Mt CO2 - gap of 222 Mts
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Residential energy use Energy consumption by households is an
important contributor to greenhouse gas emissions. 14 tonnes of CO2 per household per annum.
Population increase, larger dwelling sizes and more appliances and IT equipment per household have contributed to an increase residential energy consumption of nearly 20% 1996 -2006.
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Home energy use 2008
Space heating and cooling represent single largest component of residential energy use in Australia.
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Addressing space heating / cooling
Four critical factors1. Energy source2. Efficiency of equipment used3. Size of space being heated4. Efficiency of building shell
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To reduce this energy use and its effects on the climate, several strategies are necessary,
heat demand reduction (building size / envelope efficiency)
increased energy efficiency (heating / cooling equipment)
conversion from fossil fuels (Renewable Energy Technologies)
Energy efficiency is the most cost effective means to reduce CO2 emissions (WWF) Ceiling / wall insulation
Infiltration control Shading Improved glazing
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Addressing space heating / cooling
Four critical factors1. Energy source2. Efficiency of equipment used3. Size of space being heated4. Efficiency of building shell
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National House Energy Rating Scheme Zero stars means the building shell does
practically nothing to reduce the discomfort of hot or cold weather.
A 5 star rating current mandatory standard.
6 star rating typical international standard.
Occupants of a 10 star home are unlikely to need any artificial cooling or heating.
Move to 6 stars reduces space heating by 22%
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What’s the problem? Why not a higher performing standard
Increasing housing affordability problem Costs of operation of housing set to increase Debate over energy efficiency – affordability
vs. sustainability Lack of consensus on theory, practice and
policy LACK OF CLEAR EVIDENCE - DATA
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Housing life cycle costs & benefits - Research questions
What are the through-life costs & benefits of predominant housing forms in Australia's major cities?
What are the through-life costs & benefits of improved building envelope thermal performance & higher energy efficiency for these forms?
How might infrastructural investments affect the ongoing costs associated with housing?
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Lifecycle costing of energy efficiency upgrades 80 house plans Modelled in NatHERS software
Accurate Energy efficiency upgrade scenarios (insulation, glazing, shading)
5 stars 6 stars 7 stars 8 stars
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Criteria for energy efficiency upgrades
Parameters addressed in order of priority
STAR RATING
1. CEILING 2. INFILTRATION CONTROL
3. SHADING 4. EXTERNAL WALL
5. GLAZING 6. INTERNAL WALLS
5 star
6 star
7 star
8 star
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1. Best orientation2. Identify thermal
zones3. Additions
according to priority list
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1. Best orientation2. Identify thermal
zones3. Additions
according to priority list
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1. Best orientation2. Identify thermal
zones3. Additions
according to priority list
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Lifecycle costing LCC of energy savings 2009-2050 Low and high energy price scenarios Net Present Value in $AUS of energy bill savings
from upgrades Electricity price 2009 - 2050 Low & high price scenarios
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
$ /
kW
h
Electricity low $ /kWh
Electricity high $ /kWh
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Results The NPV of energy efficiency upgrade
depends on five critical parameters, for all upgrade scenarios
1. Orientation of design2. House size (Net conditioned floor area in
sqm)3. Time-horizon of analysis4. Energy price5. Discount rate applied
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5 star orientations performance
4.7
4.8
4.9
5
5.1
5.2
5.3N
NE
E
SE
S
SW
W
NW
Plan no. 9022
Plan no. 9021
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Capital cost upgrade from 5 stars to 6 stars performance:
Upgrade to 6 stars across all possible orientations, average of $3050.31
Upgrade to 6 stars to best performing orientation only, average of $1049.94
Mean percentage savings by optimal orientation = 97.48%
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Capital cost upgrade from 5 stars to 7 stars performance:
Upgrade to 7 stars across all possible orientations, average of $6481.16
Upgrade to 7 stars to best performing orientation only, average of $4061.49
Mean percentage saving by optimal orientation = 28.25%
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Capital cost upgrade from 5 stars to 8 & 9 stars performance:
Upgrade to 8 stars across all possible orientations, average of $28835.22
Upgrade to 8 stars to best performing orientation only, average of $9203.69
Upgrade to 9 stars to best performing orientation only, average of $26171.51
Mean percentage saving by optimal orientation (8 stars) = 65.74%
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Net Present Value of Energy Savings
Over a 40 year period, the Net Present Value of savings determined by Price of Energy assumed and more importantly Discount rate
Discount scenario 1 = 1.65%. Discount scenario 2 = 3.5%Discount scenario 3 =
8%
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Summary of findings to date:
-3000
-2000
-1000
0
1000
2000
3000
4000
5000
6000
7000
5 years 10 years 25 years 40 years
Time-horizon
NP
V $
AU
S
NPV $AUS 6 stars
NPV $AUS 7 stars
NPV $AUS 8 stars
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-2000
0
2000
4000
6000
8000
10000
5 years 10 years 25 years 40 years
Time-horizon
NP
V $
AU
S NPV $AUS 6 stars
NPV $AUS 7 stars
NPV $AUS 8 stars
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6 star s
6 star s
7 star s
7 star s
7 star s
6 star s
7 star s
8 star s
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
5 years 10 years 25 years 40 years
Time-horizon
NP
V $
AU
S
low energy price
high energy price
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Implications: Housing - a long life infrastructure that is
far more expensive to upgrade to improve energy efficiency than to construct to minimum standards.
Significant energy and emissions savings can be made through better energy efficiency
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Implications continued….reduce emissions
Three key components to reduce emissions from heating / cooling : heat demand reduction (building envelope
efficiency, orientation, house size) increased energy efficiency (heating / cooling
equipment efficiency) conversion from fossil fuels (renewable
technologies).
These can’t be addressed in isolation – eg. focus on star ratings alone
Some examples of best practice: Kronsberg, Hannover Germany:
Passive house design 15kwh/m2 (equal to approximately 8.5 stars Melbourne)
Quality assurance modelling Electricity saving campaign Solar installations Co-generation heating network
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BedZED, London UK Urban infill on site of old sewage works CHP systems, PV panels Reused – recycled material South facing living spaces to maximise
solar heat gain in winter North facing workspaces to provide in-
direct light and cool temperatures
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•Includes upfront costs, costs of yearly energy, system replacement costs•Costs higher for BAU the longer time goes•Benefits from options with RE greater as time goes on and benefits from ZEH greater after 25 years
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Conclusions: Energy efficiency can contribute
significant ‘easy gains’ for emissions reduction
Reduced energy demand equates to a reduction of risk for households
Higher energy efficiency ‘adds up’ for environmental and social criteria
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Issues of equity, intra-generational & inter-generational
Sensitivity of at-risk households to policy changes & energy price changes (AHURI, 2007).
Reduced energy demand equates to a reduction of risk for households
Conclusions continued….Issues of equity
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Challenge for industry / government - identifying effective strategies for producing an affordable / energy efficiency housing when land and building costs are highly priced
Approach – pursue low cost means of achieving higher energy efficiency / thermal performance from housing.
Conclusions continued….
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Broad strategies for industry– Passive solar design Master planning of developments for optimum
orientation Innovation – modular housing? Regulation & market efficiencies – eg. double glazing in
Europe
Government – mechanisms to achieve higher energy efficiency without disadvantaging those in vulnerable socio-economic groups
Conclusions continued…. Strategies
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Comments / Questions? Dr. John MorrisseyResearch FellowCentre for DesignDesign & Social Context PortfolioRMIT UniversityGPO Box 2476VMelbourne, Victoria 3001
Tel +61 (3) 9925 [email protected] www.rmit.edu.au/cfd/laha