Table 15 Geraldton (Rottnest) - heating energy decrease (SSP3-7.0) Error! Bookmark not defined.
Table 16 Toodyay (Upton) - projected indoor air temperature increases (°C) ....................................... 31
Table 17 Toodyay (Upton) - cooling energy increase (SSP3-7.0) 32
Table 18 Toodyay (Upton) - heating energy decrease (SSP3-7.0) Error! Bookmark not defined.
Table 19 Toodyay (Rottnest) - cooling energy increase (SSP3-7.0)
Table 20 Toodyay (Rottnest) - heating energy decrease (SSP3-7.0) Error! Bookmark not defined.
Table 21 Jindalee (Upton) - projected indoor air temperature increases (°C) .......................................
Table 22 Jindalee (Upton) - cooling energy increase (SSP3-7.0) 36
Table 23 Jindalee (Upton) - heating energy decrease (SSP3-7.0) ............... Error! Bookmark not defined.
Table 24 Jindalee Rottnest) - cooling energy decrease (SSP3-7.0) 37
Table 25 Jindalee (Rottnest) - heating energy decrease (SSP3-7.0) ............ Error! Bookmark not defined.
Table 26 Perth (Upton) - projected
Figure 15 Karratha (Barker) - cooling energy (SSP3- 7.0) Error! Bookmark not defined.
Figure 16 Karratha (Nakamura) - cooling energy (SSP3-7.0) .....................................................................
Figure 17 Geraldton (Upton) -present climate living area air temperature. Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red). ............................................
Figure 20 Geraldton (Upton) - cooling energy (SSP3-7.0)
Figure 21 Geraldton (Upton) - heating energy (SSP3-7.0) ............................. Error! Bookmark not defined.
Figure 22 Geraldton (Rottnest) - cooling energy (SSP3-7.0)
Figure 23 Geraldton (Rottnest) - heating energy (SSP3-7.0) Error! Bookmark not defined.
Figure 24 Toodyay (Upton) -present climate living area air temperature. Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Figure 27 Toodyay (Upton) - cooling energy (SSP3-7.0) .............................................................................
Figure 28 Toodyay (Upton) - heating energy (SSP3-7.0)
Bookmark not defined.
Figure 29 Toodyay (Rottnest) - cooling energy (SSP3-7.0) ..........................................................................
Figure 30 Toodyay (Rottnest) - heating energy (SSP3-7.0) Error! Bookmark not defined.
Figure 31 Jindalee (Upton) -present climate living area air temperature. Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Figure 34 Jindalee (Upton) - cooling energy (SSP3-7.0)..............................................................................
Figure 35 Jindalee (Upton) - cooling energy (SSP3-7.0)
Figure
Figure
Jindalee
(Rottnest) - heating energy (SSP3-7.0)
Bookmark not defined.
Figure 38 Perth (Upton) - present climate living area air temperature. Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red). 38
This research is supported by the Western Australian Planning Commission (WAPC), the Department of Planning, Lands and Heritage (DPLH), Development WA, the Department of Housing and Works (DHW) and the Water Corporation. The research is also supported by WA Local Governments - the City of Karratha, the City of Greater Geraldton, the Shire of Toodyay, the City of Wanneroo, the City of Cockburn, the City of Vincent, and the City of Perth.
1. Executive summary
1.1 Objectives
The specific objective of the Phase 1 research wa s to:
• Benchmark the performance of selected urban precinct and housing case studies across WA’s climate regions.
In this Phase 2 the objective is to:
• Identify changes between the current and likely future performance of urban precinct and housing case studies due to climate change
Subsequent phases will:
• Develop and evaluate the performance of design proposals to adapt urban precinct and housing case studies to projected climate change; and
• Develop principles for adaptation of WA urban precincts and housing.
This report summarises Phase 2 of the project with respect to housing performance in the future climate.
1.2 Methods
The approach taken in this research is to characterise the general performance of housing across the Western Australian climate regions through the selection and modelling of typical traditional and contemporary housing in selected case study precincts.
1.2.1
Housing case study selection
The initial selected case study precincts have been chosen with the Partner Organisations to represent cities/towns within WA’s broadscale climate regions, the ‘Monsoonal North’, ‘Rangelands’, and the South-Western Flatlands. The case study sites represent typical urban form in Broome, Karratha, Geraldton, Toodyay, and Perth’s central, eastern, and coastal areas. Individual houses were selected from Broome and Perth to represent both traditional and contemporary housing in these and other case studies across the state
1.2.2
Building energy modelling
This research element aims to establish typical housing typologies' thermal performance and energy demand using the EnergyPlus building energy modelling (BEM) software. In Phase 1 the modelling utilised input weather data produced by CSIRO for the chosen locations. Information on the selection of houses and their calibration is included in the Phase 1 report.
The most recent report of the International Panel on Climate Change (IPCC) is Assessment Report 6 (IPCC, 2023). Working Group 1 (WGI) assessed five illustrative greenhouse gas (GHG) emissions scenarios based on the so-called “Shared Socio-economic Pathways (SSPs)” which are narratives about potential future socio-economic scenarios. In this research SSP1-4.5 and SSP3-7.0 (intermediate and high emissions scenarios) have been used to evaluate potential climate
conditions in Western Australia to 2080. A detailed explanation for selection of these scenarios is included in the Phase 2 Precinct report.
1.3 Findings
1.3.1
Temporal limitations of modelling
It is important to note that these projections are only to 2080 for the selected scenarios. Global temperatures for these scenarios are projected to increase well beyond 2100, particularly for SSP37.0. Accordingly, unmet hours (the hours that a house fails to meet a thermally comfortable indoor temperature range in unconditioned houses) and energy demand in conditioned houses will likely increase beyond the results reported here unless urgent action is taken to eliminate emissions.
1.3.2 Passive performance of housing
The performance of unconditioned houses is particularly important for social housing and vulnerable families that do not have the benefit of air-conditioning. The annual percentage of hours in which the indoor air temperatures are projected to exceed the cooling setpoint (the desired temperature at which a conditioned houses’ cooling system would turn on) increases in all case study precincts although the magnitude of change varies. In summer, Broome and Karratha are already at 90100%, so the annual changes represent increasing temperatures in the shoulder seasons (Spring and Autumn). The largest changes occur in Geraldton and the Perth coastal locations where exceedances will approximately double from present conditions. In Toodyay and the Perth central and eastern locations exceedances will increase by around half.
The annual percentage of hours in which the indoor air temperatures are projected to fall below the heating setpoint (the target indoor temperature at which the heating system turns on in a conditioned house) will decline, noting that heating is already not required in Broome and Karratha. Elsewhere the magnitude of change will be 40-60%.
1.3.3 Thermal energy demand of housing
As noted in the Phase 1 report, cooling loads in the south of the state are less than half that in Broome and Karratha but exhibit no significant differences between old and new houses on a per m2 basis. The results broadly reflect latitude, but with the coastal influence observable in Geraldton and Perth.
The contemporary house design represented in the southern region case studies is around the average size of new housing in Perth (206m2 conditioned area) compared to the traditional house (67m2 conditioned area). Accordingly, the total cooling energy is proportionally higher in new housing.
Cooling energy demands are projected to increase substantially in all locations, by 20% by 2050 in Broome and Karratha, and 30-70% by 2050 elsewhere. By 2080, cooling energy demand is projected to increase by 70% in Broome and Karratha and 80-160% in Geraldton, Toodyay, and Perth. Heating energy demand is projected to decrease in the southern locations in both newer and older houses, although not by as much as cooling demand will increase.
By 2080 total energy required to condition (i.e., cool and heat) houses is projected to increase by around 17-24 GJ pa in Broome; 13-19 GJ pa in Karratha; 12-31 GJ pa in Geraldton; and 7-23 GJ pa in the other locations, with older houses seeing the largest likely increase.
1.3.4 Electricity demand
The average impact of climate change on overall electricity demand can be approximately estimated from the modelling results. Substantial increases are likely in the north of the state in older houses, but mostly after 2050. Smaller increases are likely in better performing new houses of similar size. In Geraldton smaller and older houses will likely see increases of around 15% by 2080, but higher increases in larger, newer houses. In Toodyay and Perth electricity demand will likely increase by 510% in older houses and 10-20% in newer, larger houses in the coming decades.
2. Introduction
2.1
Future Climate Future Home objectives
Through a rare collaboration between experts in urban, landscape and architectural design, public health, climate science, engineering, and climate, energy, and water modelling, this project aims to:
Generate evidence to inform solutions and policy decisions concerning the climate change adaptation of urban precincts and housing to projected temperature and rainfall changes and foster healthy and climate-resilient communities across WA’s climate regions.
The specific objective of the previous Phase (Phase 1) was to:
• Benchmark the performance of selected urban precinct and housing case studies across WA’s climate regions concerning Urban Heat Island (UHI) effects, thermal comfort of the outdoor environments, Thermal performance of housing, and irrigation demands for public and private open spaces (Phase 1).
This Phase 2 research aims to:
• Identify changes between the current and likely future performance of urban precincts and housing case studies due to climate change-induced variations in temperature and rainfall (Phase 2).
Subsequent phases will:
• Develop and evaluate the performance of design proposals to adapt urban precinct and housing case studies to projected climate change using micro-climatic, building energy, and water modelling and community engagement (Phase 3).
• Develop CSUD principles for adaptation of WA urban precincts and housing to temperature and rainfall changes for inclusion in the revision of future state and local government policies and design guidance (Phase 4)
2.2 The thermal performance of housing
This report summarises Phase 2 of the project with respect to housing performance in the likely future climate conditions The thermal performance of the unconditioned indoor environment from the perspective of human thermal comfort is characterised by several variables:
• Air temperature;
• Humidity;
• The mean radiant temperature of internal surfaces
All of these variables are affected by air movement. Air-conditioning modifies the natural indoor environment through the removal or introduction of warm air. Both the natural performance (known as the “free-running” mode and the conditioned mode (requiring energy) of house operation are important metrics reported here.
Humidity and, therefore, wet bulb temperatures are much higher in the northern regions of Western Australia, particularly in the hotter months. Air-conditioning systems both remove moisture from the
air (latent cooling) and energy from the air (sensible cooling). In the present climate in Broome, the latent cooling energy represents 30% of the annual cooling demand, while in Perth, the value is 16%.
2.3 Companion reports
This report is one of a suite of documents being prepared for Phase 2 of Future Climate Future Home:
• Housing performance report (this document)
• Precinct climate performance report
• Water Corporation precinct climate performance report
2.4 Project governance
This project capitalises upon a long-term successful research collaboration with four partner organisations: The Western Australian Planning Commission (WAPC), the Department of Planning, Lands and Heritage (DPLH), Development WA, and the Department of Housing and Works (DHW) The project also forges new collaborations with the Water Corp oration, CSIRO, and WA Local Governments - the City of Karratha, the City of Greater Geraldton, the Shire of Toodyay, the City of Wanneroo, the City of Cockburn, the City of Vincent, and the City of Perth.
Project coordination and reporting occur through biannual Partner Organisation meetings. Project updates will also be provided to AUDRC’s Advisory board, which comprises Emma Cole – Chair of the WAPC; Anthony Kannis– Chair of DPLH; Dean Mudford – CEO of Development WA, and Leon McIvor – Director-General of the DHW and the Urban Design Research and Education Committee, which includes officer-level staff from the State Government Partner Organisations.
3. Methods
The objective for Phase 2 is to compare the current and likely future performance of selected urban precinct and housing case studies across WA’s climate regions concerning UHI effects, thermal comfort of the outdoor environments, thermal performance of housing, and irrigation demands for public and private open spaces. The focus of this report is the thermal performance of housing.
3.1 The case study precincts
The rationale for the selection of case study precincts (Table 1), and descriptions of related climate conditions are outlined in the Phase 1 reports.
Table 1: The case study precincts
Case study
Broome North Monsoonal north Compact suburb Shire of Broome DevWA
Broome traditional suburb Monsoonal north Traditional suburb Shire of Broome DHW
Bulgarra, Karratha Rangelands Radburn suburb City of Karratha DHW
Karratha town centre Rangelands Medium density precinct City of Karratha DevWA
Maitland Park Geraldton Southern and southwestern flatlands Park and schools City of Greater Geraldton
Toodyay, River Hills Estate Southern and southwestern flatlands Traditional main street/ suburb Shire of Toodyay DPLH/ WAPC
Jindalee Southern and southwestern flatlands Compact suburb City of Wanneroo DPLH/ WAPC
Established/ planned Broome North Waranyjarri Estate Design Guidelines
State Planning Policy 7.3- Residential Design Codes
The Broome North Structure Plan
The Kimberley Vernacular Handbook
State Planning Policy 7.0 Design of the Built Environment
Established/ planned Shire of Broome Local Planning Strategy
State Planning Policy 7.3- Residential Design Codes
State Planning Policy 7.0 Design of the Built Environment
Established State Planning Policy 7.3- Residential Design Codes
The City of Karratha Local Planning Strategy
The Pilbara Vernacular Handbook
State Planning Policy 7.0 Design of the Built Environment
Established/ planned The City of Karratha Local Planning Strategy
State Planning Policy 7.2 - Precinct Design
State Planning Policy 7.0 Design of the Built Environment
Established/ planned Maitland Park Concept Masterplan Report
Broader planning for the precinct is encompassed in the City of Geraldton Local Planning Strategy
State Planning Policy 7.2 - Precinct Design
State Planning Policy 7.3- Residential Design Codes
Volume 2 - Apartments
Public Parkland Planning & Design Guide
State Planning Policy 7.0 Design of the Built Environment
Established/ planned Shire of Toodyay Local Planning Strategy
Liveable Neighbourhoods
State Planning Policy 7.3- Residential Design Codes
State Planning Policy 7.0 Design of the Built Environment
Established Liveable Neighbourhoods Policy
Residential Design Codes Volume 1 for single houses and group dwellings below R60
State Planning Policy 7.0 Design of the Built Environment
Nollamara Southern and southwestern flatlands Infill suburb - DHW
Leederville town centre Southern and southwestern flatlands
Central Perth Southern and southwestern flatlands
Medium-density precinct/ TOD City of Vincent DPLH/ WAPC
Medium to highdensity precinct City of Perth -
Karawara, South Perth Southern and southwestern flatlands Radburn suburb - DHW
Cockburn Central Southern and southwestern flatlands
Salt Lane Southern and southwestern flatlands
Medium-density precinct/ TOD City of Cockburn DHW
Established State Planning Policy 7.3- Residential Design Codes
The City of Stirling Planning Scheme No. 3
State Planning Policy 7.0 Design of the Built Environment
Planned State Planning Policy 4.2 Activity centres
State Planning Policy 7.2 - Precinct Design
State Planning Policy 7.0 Design of the Built Environment
Established State Planning Policy 7.2 - Precinct Design
State Planning Policy 7.3- Residential Design Codes Volume 2 –Apartments
State Planning Policy 7.0 Design of the Built Environment
Established Liveable Neighbourhoods policy
State Planning Policy 7.3- Residential Design Codes
State Planning Policy 7.0 Design of the Built Environment
Established/ planned
Medium density precinct City of Cockburn DevWA
Established/ planned
State Planning Policy 4.2 Activity centres
State Planning Policy 7.2 - Precinct Design
State Planning Policy 7.3- Residential Design Codes Volume 2 –Apartments
Design guidelines for Cockburn Central West
State Planning Policy 7.0 Design of the Built Environment
State Planning Policy 7.2 - Precinct Design Cockburn Coast Design Guidelines for Robb Jetty and Emplacement
State Planning Policy 7.0 Design of the Built Environment
3.2 House selection
Individual houses were selected from Broome and Perth to represent both older and contemporary forms of housing (Table 1). These case study houses were then modelled for their performance in the case study precincts across the state, and the results are reported in the Phase 1 housing performance report
Table 2: Housing case study selection by region
Northern regions: Broome and Karratha
Traditional house (Barker St)
Based on a Department of Housing and Works, 1970s, two-bedroom/ one-bathroom detached house in Barker St in the old centre of Broome.
Contemporary house (Nakamura Ave)
Based on a recently constructed two-bedroom/ two-bathroom new detached Department of Housing and Works house in Nakamura Ave, Broome North.
Midwest and southern regions: Geraldton, Toodyay, and Perth
Traditional House (Upton St)
Based on an older 1950s two-bedroom/ one-bathroom detached house owned by the Department of Housing and Works at 8 Upton Street, Saint James
Contemporary House (Rottnest St)
Based on a new large four-bed display home at 7 Rottnest Street, Bushmead
3.2.1 House types for Northern regions: Broome and Karratha
Traditional house (Barker St)
This case study is based on a Department of Housing and Works 2-bedroom/1-bathroom traditional detached house in the old centre of Broome at 8/18 Barker St, Broome (see Figure 1 and Figure 2). The house is an ‘L’ shape, and the living areas of the house are oriented to the south and east. The construction is a timber stud frame, with external and internal walls clad in asbestos sheeting. The roof is framed with timber rafters, battens, and ceiling joints. The roof is clad with asbestos-cement corrugated roof sheeting. Photos of the house are set out in the Appendix.
Contemporary house (Nakamura Ave)
This case study is based on a recently constructed two-bedroom new detached Department of Housing and Works house in Broome North at 11A Nakamura Ave, Bilingurr See Figure 3 and Figure 4 The house has 2 bedrooms/1 bathroom and construction is a steel stud frame, with external and internal walls clad in Colorbond sheeting, with R2 batts in external walls and R1.5 bulk installation in internal walls. The roof is steel-framed with Colorbond cladding and weatherboard, and features R3 ceiling insulation and 750 mm roof eaves. Photos of the house are set out in the Appendix.
3.2.2 House types for the mid-west and southern regions: Geraldton, Toodyay, and Perth
Traditional house (Upton St)
This case study is based on an older 1950s two-bedroom detached house owned by the Department of Housing and Works at 8 Upton Street, Saint James. See Figure 5 and Figure 6. The
Figure 1: Barker St: Aerial image
Figure 2: Barker St- floor plan
Figure 3: Nakaumura Ave – aerial image
Figure 4: Nakamura Ave - Floor plan
house is a 2-bedroom, 1- bathroom house with living areas facing south-west. Construction is cavity brick external walls and tiled roof, with a suspended timber floor supported by limestone blocks. Photos of the house are set out in the Appendix.
Contemporary house (Rottnest St)
This case study is based on a new large 4-bedroom, 2-bathroom display home at 7 Rottnest Street, Bushmead. See Figure 7 and Figure 8. Living areas face south. The construction is an external cavity brick wall, single brick for internal wall, corrugated iron roof, and an insulated ceiling with an R-value of 4.1. Photos of the house are set out in the Appendix.
Figure 5 Upton St - aerial image
Figure 6 Upton St - floor plan
Figure 7 Rottnest St - aerial image
Figure 8 Rottnest St – floorplan
3.3 Building performance modelling
3.3.1
EnergyPlus
This research element aims to establish typical housing typologies’ thermal performance and energy demand using building energy modelling (BEM) software, EnergyPlus (EnergyPlus, 2024). EnergyPlus is funded by the U.S. Department of Energy’s (DOE) Building Technologies Office (BTO) and managed by the National Renewable Energy Laboratory (NREL).
All BEM software relies on weather files (epw files), developed initially for EnergyPlus but now widely used. CSIRO has produced a dataset of ‘Typical meteorological year (TMY) weather files in epw format’, comprising one year of weather data at hourly intervals for one of 83 Australian locations. The dataset is based on weather files developed for the Nationwide House Energy Rating Scheme (NatHERS) residential building simulation tools. The typical meteorological year weather dataset is based on historical weather data drawn from 1990 to 2015 using the method described by the New Zealand National Institute of Water and Atmospheric Research (NIWA). These files were used for the Phase 1 study’s ENV-met and BEM modelling Each selected house was modelled in EnergyPlus, and the models were calibrated against instrumentation data collected during typical summer conditions (see the Phase 1 housing report)
3.3.2
Future weather files
The most recent report of the International Panel on Climate Change (IPCC) is Assessment Report 6 (IPCC, 2023). Working Group 1 (WGI) assessed five illustrative greenhouse gas (GHG) emissions scenarios based on CMIP6 models, including economic Pathways (SSPs)” which are narratives about potential future socio-economic scenarios. The future climate scenarios are based on global climate models produced by the Coupled Model Intercomparison Project (CMIP), an international scientific collaboration. The CMIP project phase 6 (CMIP6) ensemble of model simulations was the key input to the IPCC Sixth Assessment Report. It involves many models contributed from numerous countries around the world.
In this research, SSP1-4.5 and SSP3-7.0 have been used to evaluate potential climate conditions in Western Australia to 2080. A summary of the scenarios is set out in Table 3. It is important to note that, under both scenarios, temperatures are projected to continue to increase well beyond 2100.
Table 3 SSP GHG emissions scenarios
Scenario Emissions Limits warming to (by 2100): Likelihood
SSP1-1.9 Very low 1.5°C with no or limited overshoot >50%
SSP1-2.6 Low 2°C >67%
SSP2-4.5 Intermediate 3°C >50%
SSP3-7.0 High 4°C >50%
SSP5-8.5 Very high Exceeds 4°C >50%
CSIRO has also produced a set of files representing future weather, but these are based on the CMIP5 global climate models, rather than the latest CMIP6 models. Accordingly, for this research, we have used the Future Weather Generator software developed by the “Energy for Sustainability
Initiative” at the University of Coimbra (Portugal) (Rodrigues, Fernandes, & Carvalho, 2023). The software produces weather files based on the CMIP6 models, including those for the SSP scenarios selected for this study. For this Phase 2 research, the CSIRO TMY files were morphed using the software to produce epw files for each of the case study NatHERS climate zones for:
• SSP3-7.0 at 2050 and 2080; and
• SSP2-4.5 at 2080.
3.3.3 Performance metrics
The performance of unconditioned modes of operation is reported for each month of the year as:
• the hourly average air temperatures in living areas;
• the percentage of hours that living space air temperatures either exceed the cooling setpoint (which varies by location) or are lower than the heating setpoint; and
• the differences between present and likely future performance.
The performance of conditioned modes of operation is reported as:
• the monthly energy consumption required to achieve the cooling and heating setpoints for the location; and
• the differences between present and likely future performance.
The setpoints as set out by NatHERS (Chen, 2016) were used with the exception that a figure of 18°C was used for the heating setpoint in sleeping spaces during all hours (Table 4). The heating setpoint in other spaces is 20°C.
Table 4: Cooling setpoints by centre.
4. Results
The detailed results of the simulations are set out in the Appendix. The focus of this phase of the research is to identify likely changes in housing thermal performance between the present and future climates. The older houses (Barker St, and Upton St) are less likely to have air conditioning, so their unconditioned performance is reported. The energy demand for both older and more contemporary houses is also reported.
4.1 Broome
4.1.1
Traditional house – unconditioned performance
As noted in the Phase 1 report, conditions in the older Broome house are uncomfortable in the current climate with indoor temperatures near or above 30°C day and night from November to February (Figure 9).
Average monthly temperatures (Time of day)
Feb
Mar
Apr
May 25.225.024.624.323.923.723.223.523.925.526.427.027.528.028.328.628.728.728.928.627.927.226.625.826.3
Jun 23.623.323.022.922.622.121.922.322.723.724.625.325.826.226.626.827.027.026.626.125.524.924.423.724.5
Oct 27.727.326.826.326.126.226.227.328.829.329.229.329.529.729.829.929.929.730.030.129.729.329.228.328.6
Nov 30.530.129.829.629.228.929.130.531.631.731.531.531.731.831.931.931.831.631.832.331.931.731.730.931.0
Dec 30.830.630.230.129.829.629.731.031.832.131.931.831.932.032.132.032.031.932.232.732.432.231.931.131.4
Ann ave 27.427.126.926.626.426.126.026.727.528.328.628.829.229.429.629.829.829.729.929.929.429.028.727.828.3
Figure 9 Broome (Barker) -present climate living area air temperature Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red)
Indoor conditions are projected to worsen under climate change, with the largest increases in the shoulder months of March – May and September – November (Table 5 and Figure 10).
Table 5 Broome (Barker) - projected indoor air temperature increases (°C)
(SSP34.5)
4.1.2 Conditioned performance – traditional house
The conditioned performance of the traditional (Barker) house reflects the unconditioned performance with cooling energy projected to increase by 73% by 2080 under SSP3-7.0 (Table 6 and Figure 11).
Table 6 Broome (Barker) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 increase 2080 increase
Jan 6,176 632 1,737
Feb 4,854 1,003 2,139
Mar 4,517 1,354 2,578
Apr 3,273 1,100 2,893
May 838 267 1,999
Jun 170 177 912
Jul 41 94 448
Aug 74 127 727
Sep 602 407 1,796
Oct 2,212 1,010 2,494
Nov 4,446 1,073 2,955
Dec 5,253 1,344 2,880
32,456 8,588 23,558 26% 73%
4.1.3
Conditioned performance – contemporary house
The cooling energy demand of the newly constructed (but similar size) Nakamura house is projected to increase by 57% by 2080 under SSP3-7.0 (Table 7 and Figure 12).
Table 7 Broome (Nakamura) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 increase 2080 increase
Jan 4,723 735 1,378
Feb 4,063 617 1,269
Mar 4,055 937 1,622
Apr 3,226 767 1,925
May 1,230 238 1,701
Jun 456 214 936
Jul 176 180 654
Aug 283 200 944
Sep 929 400 1,554
Oct 2,401 772 1,821
Nov 4,098 693 1,823
Dec 4,590 806 1,678
30,230 6,561 17,306 22% 57%
Figure 11 Broome (Barker) - cooling energy (SSP3-7.0)
Figure 12 Broome (Nakamura) - cooling energy (SSP3-7.0)
4.2 Karratha
4.2.1 Traditional house – unconditioned performance
As noted in the Phase 1 report, conditions in the Karratha traditional house (Based on the Department of Housing’s Barker St house in Broome) are uncomfortable in the current climate, with indoor temperatures near or above 30°C day and night from January to March (Figure 13).
Average monthly temperature (Time of day)
0123456789
1011121314151617181920212223 Mthly ave
Jan 30.230.029.729.329.228.828.529.630.931.531.531.631.932.132.332.432.332.232.432.632.131.931.730.731.1
Feb 31.431.030.730.630.430.229.930.631.732.232.432.532.733.033.333.433.333.033.233.532.932.832.731.832.0
Mar 30.830.530.129.829.529.228.729.330.631.331.531.732.032.432.632.632.632.532.632.932.532.432.131.331.3
Oct 27.126.526.125.825.425.024.826.128.028.929.129.429.830.130.330.430.330.230.330.229.329.028.427.628.2
Nov 28.227.827.527.026.526.226.228.029.830.530.530.731.031.231.431.531.431.231.431.430.229.729.328.629.5
Dec 28.728.428.227.927.727.627.529.030.431.131.131.231.431.631.831.831.731.431.331.230.530.129.929.330.0
Ann ave 26.326.025.625.425.124.924.725.526.627.427.728.128.528.829.129.229.229.129.028.628.027.827.726.827.3
Figure 13 Karratha (Barker) -present climate living area air temperature Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Indoor conditions are projected to worsen under climate change, with the largest increases in the shoulder months of March – May and October – December (Table 8 and Figure 14).
Table 8 Karratha (Barker) - projected indoor air temperature increases (°C) Present 2050 2080 2080 (SSP37.0) (SSP34.5) (SSP37.0)
4.2.2
Conditioned performance – traditional house
The conditioned performance of the traditional (Barker) house reflects the unconditioned performance with cooling energy projected to increase by 68% by 2080 under SSP3-7.0 (Table 9 and Figure 15).
Table 9 Karratha (Barker) - cooling energy increase (SSP3-7.0) Cooling energy (MJ pa)
4.2.3 Conditioned performance – contemporary house
The cooling energy demand of the newly constructed (but similar size) house in Nakamura Ave in Broome) is projected to increase by 55% by 2080 under SSP3-7.0 (Table 10 and Figure 16).
Table 10 Karratha (Nakamura) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Jan
Feb
Jun
Jul
Aug
Oct
Figure 16 Karratha (Nakamura) - cooling energy (SSP3-7.0)
4.3 Geraldton
4.3.1
Traditional house – unconditioned performance
Conditions in the Geraldton traditional house (based on the Department of Housing’s Upton Street house in Perth) are mostly comfortable in the current climate, with indoor temperatures only above the cooling setpoint of 25°C during the day from December to March. Temperatures are near or below the heating setpoint of 20°C for a significant period, day and night, from June to September (Figure 17)
Average monthly temperature (Time of day)
0123456789 1011121314151617181920212223 Mthly ave
Jan 23.523.223.023.023.423.623.424.025.226.426.627.027.427.727.928.128.328.428.026.424.924.224.023.625.5
Feb 24.624.724.824.724.624.624.425.126.127.127.527.928.328.628.929.229.229.128.527.226.025.525.525.226.6
Mar 24.724.424.724.924.624.424.325.125.726.326.727.227.627.928.428.528.528.327.526.125.324.924.824.626.1
May 21.721.621.521.421.221.120.921.621.722.022.222.723.123.624.024.224.123.723.023.123.223.423.322.222.5 Jun 19.819.619.419.219.018.818.619.519.820.119.720.020.420.921.321.621.721.722.021.821.821.821.620.220.4 Jul 18.017.817.617.317.116.916.717.718.118.318.018.218.719.319.720.020.220.120.720.520.420.320.118.518.8 Aug 18.318.017.817.617.417.117.018.018.418.818.518.719.119.519.920.220.520.520.820.920.720.520.418.819.1 Sep 19.419.118.918.718.518.318.119.119.619.919.720.020.320.721.121.321.420.921.321.821.621.521.520.020.1 Oct 21.421.221.220.920.620.420.321.321.822.122.222.522.923.223.623.723.723.222.622.723.123.323.321.822.2 Nov 22.021.922.122.122.021.921.622.723.123.824.124.424.624.825.125.325.424.924.122.922.222.422.622.423.3 Dec 22.522.822.822.822.722.622.623.624.225.225.526.026.326.526.626.826.826.425.824.723.522.922.622.324.4 Ann ave 21.621.521.421.321.221.020.921.722.322.822.923.323.724.024.424.624.724.424.123.523.022.922.922.022.8
Figure 17 Geraldton (Upton) -present climate living area air temperature. Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Under future climate conditions, indoor temperatures are projected to increase by up to 3°C in the summer months (December to March) by 2080. Accordingly, temperatures will exceed the cooling setpoint throughout daytime and night-time hours for an increasing number of hours December –April (Table 11 and Figure 18). The number of hours the temperature falls below the heating setpoint will decline from June to September (Figure 19).
Table 11 Geraldton (Upton) - projected indoor air temperature increases (°C)
Present 2050 2080 2080 (SSP37.0) (SSP34.5) (SSP37.0) Daily average Average increase
The conditioned performance of the traditional house (based on the Department of Housing’s Upton St house in Perth) reflects the unconditioned performance with cooling energy projected to increase significantly by 137% by 2080 under SSP3-7.0 (Table 12 and Figure 20).
Table 12 Geraldton (Upton) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa) Present 2050 2080 increase increase
Jan 2,039 1,546 2,918
Feb 2,532 1,038 2,745
Mar 2,077 987 2,584
Apr 702 650 1,335
May 196 156 353
Jun 10 21 58
Jul - 1 2
Aug - 0 12
Sep 1 10 39
Oct 261 123 419
Nov 541 271 806
Dec 1,218 802 1,830 9,579 5,604 13,101 59% 137%
20 Geraldton (Upton) - cooling energy (SSP3-7.0)
Heating energy demand will decrease by around 57% by 2080 under SSP3- 7.0 (Table 13 and Figure 21).
Table 13 Geraldton (Upton) - heating energy decrease (SSP3-7.0)
Heating energy (MJ pa) Present 2050 2080 decrease decrease
Jan 2 2 2
Feb 1 1 1
Mar 4 4 4
Apr 2 1 1
May 151 109 125
Jun 214 32 102
Jul 639 196 303
Aug 637 217 409
Sep 341 123 171
Oct 142 14 95
Nov 47 9 33
Dec 10 7 10 2,191 715 1,257 33%
21 Geraldton (Upton) - heating energy (SSP3-7.0)
Figure
Figure
4.3.3
Conditioned performance – contemporary house
The conditioned performance of the contemporary house (based on the large Rottnest display house in Perth) reflects the unconditioned performance with cooling energy projected to increase significantly by 97% by 2080 under SSP3-7.0 (Table 14 and Figure 22).
Table 14 Geraldton (Rottnest)cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa) Present 2050 2080 increase increase
Jan 5,593 3,265 6,023
Feb 6,723 2,290 5,458
Mar 6,641 2,145 5,357
Apr 3,632 1,560 3,071
May 1,733 653 1,345
Jun 531 370 803
Jul 254 150 291
Aug 209 154 458
Sep 314 260 622
Oct 1,221 510 1,566
Nov 1,988 976 2,597
Dec 4,100 2,016 4,256 32,939 14,350 31,847 44% 97%
22
- cool ing energy (SSP3-7.0)
Heating energy demand will decrease by around 23% by 2080 under SSP3- 7.0 (Table 15 and Figure 23).
Table 15 Geraldton (Rottnest) - heating energy decrease (SSP3-7.0)
Heating energy (MJ pa) Present 2050 2080 decrease decrease
Jan 152 96 136
Feb 88 78 88
Mar 147 23 90
Apr 407 - 75 116 May 980 293 394
Jun 801 52 - 41
Jul 715 41 - 39
Aug 650 - 239 51
Sep 508 95 102
Oct 361 54 173
Nov 237 63 86
Dec 153 - 45 19 5,200 438 1,176 8% 23%
23 Geraldton (Rottnest) - heating energy (SSP37.0)
Figure
Geraldton (Rottnest)
Figure
4.4.1 Traditional house – unconditioned performance
Indoor temperatures in the Toodyay traditional house (based on the Department of Housing’s Upton Street house in Perth) are near or above the cooling setpoint of 26°C during the night and day from December to February and in the evenings in March and November in the current climate. Temperatures are near or below the heating setpoint of 20°C for a significant period day and night from May – September (Figure 24).
Average monthly temperature (Time of day)
0123456789
Jan
Feb
Mar 25.224.724.323.923.523.323.323.924.224.724.825.225.726.326.627.027.628.028.227.827.527.026.525.425.6
Oct 22.121.821.621.521.321.020.821.722.122.722.422.522.923.724.224.825.425.625.725.124.724.524.022.623.1
Nov 23.022.522.422.021.821.621.522.723.424.023.924.224.624.925.425.826.727.527.927.126.325.725.424.024.3
Dec 26.726.325.925.625.024.625.126.026.627.327.127.327.628.128.629.029.730.230.730.229.228.628.627.327.6
Ann ave 22.021.721.421.120.920.620.521.421.922.222.022.322.823.323.724.124.624.925.324.924.524.123.922.522.8
Figure 24 Toodyay (Upton) -present climate living area air temperature Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Under future climate conditions the indoor temperatures are projected to increase by up to 2-3°C in October to March by 2080. Accordingly, temperatures will exceed the cooling setpoint throughout daytime and night-time hours for an increasing number of hours November – April (Table 16 and Figure 25). The number of hours in which the temperature falls below the heating setpoint will decline May – September (Figure 26).
Table 16 Toodyay (Upton) - projected indoor air temperature increases (°C)
25 Toodyay
- hours above cooling setpoint
26 Toodyay
- hours below heating setpoint
4.4.2 Conditioned performance – traditional house
The conditioned performance of the traditional (Upton) house reflects the unconditioned performance with cooling energy projected to increase significantly by 86% by 2080 under SSP3-7.0 (Table 17 and Figure 27).
Figure
(Upton)
(26°C)
Figure
(Upton)
(20°C)
Table 17 Toodyay (Upton ) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 3,677 1,167 1,972
Feb 2,259 833 1,552
Mar 1,424 180 1,468
Apr 360 47 692
May 25 16 57
Jun - - -
Jul - - -
Aug 7 13 69
Sep 66 66 228
Oct 351 197 727 Nov 1,065 502 1,353
- cooling energy (SSP3-7.0)
Heating energy demand will decrease by around 54% by 2080 under SSP3- 7.0 (Table 18 and Figure 28).
Table 18 Toodyay (Upton) - heating energy decrease (SSP3-7.0)
Heating energy (MJ pa) Present 2050 2080 decrease decrease
Mar 7 3 6
Apr 36 17 32
May 472 172 291
Jun 1,430 416 872
Jul 1,799 540 757
Aug 905 242 528
Sep 317 113 179
Oct 63 16 18
Nov 62 46 54
Dec 6 -1 4 5,099 1,565 2,743 31% 54%
28 Toodyay
- heating energy (SSP3-7.0)
Figure 27 Toodyay (Upton)
Figure
(Upton)
4.4.3
Conditioned performance – contemporary house
The conditioned performance of the contemporary house (based on the large Rottnest display house in Perth) reflects the unconditioned performance with cooling energy projected to increase significantly by 74% by 2080 under SSP3-7.0 (Table 19 and Figure 29).
Table 19 Toodyay (Rottnest) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 8,574 2,452 4,222
Feb 6,115 1,751 3,421
Mar 4,570 477 3,484
Apr 2,193 132 1,853
May 646 187 489
Jun 126 63 145
Jul 76 56 119
Aug 328 144 527
Sep 687 394 1,090
Oct 1,783 711 2,236
Nov 3,142 1,355 3,412
Dec 6,722 2,599 4,836 34,960 10,321 25,834 30% 74%
29 Toodyay
- cooling energy (SSP3-7.0)
Heating energy demand will decrease by around 46% by 2080 under SSP3- 7.0 (Table 20and Figure 30).
Table 20 Toodyay (Rottnest) - heating energy decrease (SSP3-7.0)
Heating energy (MJ pa) Present 2050 2080 decrease decrease
Jan 1,086 374 925
Feb 638 476 479
Mar 836 -238 430
Apr 993 -227 310
May 445 166 10
Jun 907 373 510
Jul 1,304 515 730
Aug 805 236 449
Sep 380 32 -1
Oct
Figure 30 Toodyay (Rottnest) - heating energy (SSP3-7.0)
Figure
(Rottnest)
4.5 Perth – northern coastal locations
4.5.1
Traditional house – unconditioned performance
The Jindalee case study in Perth’s coastal north is situated in the NatHERS climate zone CZ52). Indoor temperatures in the traditional house (based on the Department of Housing’s Upton Street house in Perth) are near or above the cooling setpoint of 24.7°C during the night and day from December to February and in the middle of the day in March. Temperatures are near or below the heating setpoint of 20°C for a significant period day and night from May – September (Figure 31).
Average monthly temperature (Time of day)
Sep
Nov
Dec 22.922.923.023.023.122.9 22.823.724.224.624.6 24.825.225.325.325.425.425.2 25.024.323.623.623.623.224.1
Ann ave 21.020.920.820.720.520.320.121.121.421.821.721.922.222.522.722.922.822.622.722.522.322.322.421.321.7
Figure 31 Jindalee (Upton) -present climate living area air temperature. Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Under future climate conditions the indoor temperatures are projected to increase by up to 2-3°C in December to March by 2080. Accordingly, temperatures will exceed the cooling setpoint throughout daytime and night-time hours for an increasing number of hours December – April (Table 21 and Figure 25). The number of hours in which the temperature falls below the heating setpoint will decline May – September (Figure 26).
Table 21 Jindalee (Upton) - projected indoor air temperature increases (°C)
32 Jindalee
- hours above cooling setpoint
33 Jindalee
4.5.2 Conditioned performance – traditional house
The conditioned performance of the traditional (Upton) house reflects the unconditioned performance with cooling energy projected to increase significantly by 159% by 2080 under SSP3-7.0 (Table 22 and Figure 34).
Figure
(Upton)
(25°C)
Figure
(Upton) - hours below heating setpoint (20°C)
Table 22 Jindalee (Upton) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa) Present 2050 2080 increase increase
Heating energy demand will decrease by around 36% by 2080 under SSP3- 7.0 (Table 23 and Figure 35).
Table 23 Jindalee (Upton) - heating energy decrease (SSP3-7.0)
(MJ
Figure 34 Jindalee ( Upton) - cooling energy (SSP3-7.0)
Figure 35 Jindalee (Upton) - cooling energy (SSP3-7.0)
4.5.3 Conditioned performance – contemporary house
The conditioned performance of the contemporary house (based on the large Rottnest display house) reflects the unconditioned performance with cooling energy projected to increase significantly by 122% by 2080 under SSP3-7.0 (Table 24 and Figure 36).
Table 24 Jindalee Rottnest) - cool ing energy decrease (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 3,321 3,013 5,174
Feb 5,375 1,693 3,929
Mar 3,634 1,660 4,163
Apr 1,880 1,010 2,005
May 607 497 906
Jun 144 146 319
Jul 140 120 159
Aug 127 101 209
Sep 152 120 290
Oct 411 344 980
Nov 1,427 1,013 2,260
Dec 2,932 1,858 4,285 20,149 11,572 24,677 57% 122%
Heating energy demand will decrease by around 19% by 2080 under SSP3- 7.0 (Table 25 and Figure 37).
Table 25 Jindalee ( Rottnest) - heating energy decrease (SSP3-7.0)
Heating energy (MJ pa)
Present 2050 2080 decreas e decreas e
Jan 532 477 481
Feb 629 225 529
Mar 937 180 706
Apr 1,197 31 415
May 1,019 46 75
Jun 509 -56 -623
Jul 621 63 -68
Aug 943 216 -106
Sep 699 3 -158
Oct 674 -79 -112
Nov 1,065 220 285
Dec 729 74 408 9,555 1,399 1,831 15% 19%
37 Jindalee (Rottnest) - heating energy (SSP3-7.0)
Figure 36 Jindalee ( Rottnest) - cool ing energy (SSP3-7.0)
Figure
4.6 Perth – central and eastern locations
4.6.1
Traditional house – unconditioned performance
The Nollmara, Karawara and Perth Central case studies in Perth’s central locations are situated in the NatHERS climate zone CZ13). Indoor temperatures in the traditional house (based on the Department of Housing’s Upton Street house in Perth) are near or above the cooling setpoint of 25.4°C during the night and day from December to March. Temperatures are near or below the heating setpoint of 20°C for a significant period day and night from May – September (Figure 38).
Average monthly temperature (Time of day)
Jul
Aug
Sep
Oct
Nov
Dec
Ann
Figure 38 Perth (Upton) - present climate living area air temperature Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Under future climate conditions the indoor temperatures are projected to increase by up to 2-3°C in December to March by 2080. Accordingly, temperatures will exceed the cooling setpoint throughout daytime and night-time hours for an increasing number of hours December – April (Table 26 and Figure 39). The number of hours in which the temperature falls below the heating setpoint will decline May – October ( Figure 40).
Table 26 Perth (Upton) - projected indoor air temperature increases (°C)
4.6.2 Conditioned performance – traditional house
The conditioned performance of the traditional (Upton) house reflects the unconditioned performance with cooling energy projected to increase significantly by 227% by 2080 under SSP3-7.0 (Table 27 and Figure 41).
Table 27 Perth (Upton) - cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 2,357 1,168 2,199
Feb 2,074 773 1,947
Mar 1,643 740 1,958
Apr 228 292 633
May 10 24 45
Jun - 0 3
Jul - - -
Sep 0 1 11 Oct 56 74 264 Nov 560 410 861
-
Heating energy demand will decrease by around 184% by 2080 under SSP3-7.0 (Table 28 and Figure 42).
Table 28 Perth (Upton) heating energy decrease (SSP3-7.0)
Heating energy (MJ pa)
Present 2050 2080 decrease decrease
Jan 23 13 20
Feb 18 12 17
Mar 9 4 6
Apr 80 65 76
May 467 121 318
Jun 1,003 358 510
Jul 1,194 282 476
Aug 1,244 323 749
Sep 551 238 295
Oct 375 32 198
Nov 122 52 94
Dec 31 11 15 5,117 1,511 2,774 30% 184%
42
(Upton) - heating energy (SSP3-7.0)
Figure 41 Perth (Upton)
cooling energy (SSP3-7.0)
Figure
Perth
4.6.3 Conditioned performance – contemporary house
The conditioned performance of the contemporary house (based on the large Rottnest display house) reflects the unconditioned performance with cooling energy projected to increase significantly by 96% by 2080 under SSP3-7.0 (Table 29 and Figure 43).
Table 29 Perth ( Rottnest) cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 5,743 2,644 4,900
Feb 5,108 2,181 4,630 Mar 5,305 1,790 4,398
Apr 1,719 1,065 2,055
May 383 232 433
Jun 72 107 231
Jul 61 57 66
Oct 520 363 1,147 Nov 1,915 1,119 2,373 Dec 5,228 2,188 4,619
cooling energy (SSP3-7.0)
Heating energy demand will decrease by around 40% by 2080 under SSP3- 7.0 (Table 30 and Figure 44).
Table 30 Perth ( Rottnest) heating energy decrease (SSP3-7.0)
Heating energy (MJ pa)
Present 2050 2080 decrease decrease
Jan 423 185 388
Feb 500 332 271
Mar 691 320 476
Apr 870 348 574
May 527 -283 37
Jun 683 245 144
Jul 1,121 207 211
Aug 1,173 315 710
Sep 838 301 258
Oct 698 -38 -41
44 Perth (Rottnest) - heating energy (SSP3-7.0)
Figure 43 Perth ( Rottnest) -
Figure
4.7 Perth – southern coastal locations
4.7.1
Traditional house – unconditioned performance
The Cockburn Central and Salt Lane case studies in Perth’s southern coastal locations are situated in the NatHERS climate zone CZ54). Indoor temperatures in the traditional house (based on the Department of Housing’s Upton Street house in Perth) are near or above the cooling setpoint of 24.9°C during the night and day from December to March. Temperatures are near or below the heating setpoint of 20°C for a significant period day and night from June – September (Figure 45).
Average monthly temperature (Time of day)
Jan
Feb
Under future climate conditions the indoor temperatures are projected to increase by up to 2-3°C in December to March by 2080. Accordingly, temperatures will exceed the cooling setpoint throughout daytime and night-time hours for an increasing number of hours December – April (Table 31 and Figure 46). The number of hours in which the temperature falls below the heating setpoint will decline May – October ( Figure 47). 0123456789
Mar 23.923.923.723.623.423.223.123.723.924.123.824.424.925.325.525.625.725.725.424.824.424.324.223.624.3
Oct 20.620.520.320.119.919.819.620.721.121.120.820.720.821.021.221.421.621.822.422.422.422.422.521.121.1
Nov 21.821.621.421.220.920.720.521.621.922.222.322.722.923.223.523.724.023.923.322.522.523.223.322.222.4
Dec 24.124.023.823.723.623.523.424.124.625.125.125.225.525.825.926.126.226.326.326.025.525.225.124.324.9
Ann ave 21.121.020.820.620.520.320.221.121.421.721.421.722.022.322.622.722.922.823.022.722.622.622.521.421.7
Figure 45 Cockburn (Upton) -present climate living area air temperature Cell colour intensity reflects the temperature within the range i.e. minimum (blue) to maximum (red).
Table 31 Cockburn ( Upton) - projected indoor air temperature increases (°C)
4.7.2 Conditioned performance – traditional house
The conditioned performance of the traditional (Upton) house reflects the unconditioned performance with cooling energy projected to increase significantly by 152% by 2080 under SSP3-7.0 (Table 32 and Figure 48).
Table 32 Cockburn ( Upton) cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 1,379 1,214 2,373
Feb 1,835 826 2,063
Mar 895 663 1,671
Apr 135 209 445
May 15 81 161
Jun - - -
Jul - - -
Aug - - 0
Sep - 0 8
Oct 20 39 185
Nov 116 143 389 Dec 1,582 731 1,806 5,977 3,906 9,102 65% 152%
-
Heating energy demand will decrease by around 32% by 2080 under SSP3- 7.0 (Table 33 and Figure 49).
Table 33 Cockburn (Upton) heating energy decrease (SSP3-7.0)
Heating energy (MJ pa)
Present 2050 2080 decrease decrease
Jan 64 59 64
Feb 5 3 5
Mar 13 12 13
Apr 160 71 145
May 242 133 195
Jun 960 303 431
Jul 980 323 538
Aug 534 -74 -263
Sep 561 5 -169
Oct 539 25 236
Nov 185 49 129
Dec 47 30 38 4,292 939 1,362 22% 32%
Figure 48 Cockburn (Upton)
cooling energy (SSP3-7.0)
Figure 49 Cockburn (Upton) - heating energy (SSP3-7.0)
4.7.3
Conditioned performance – contemporary house
The conditioned performance of the contemporary house (based on the large Rottnest display house) reflects the unconditioned performance with cooling energy projected to increase significantly by 117% by 2080 under SSP3-7.0 (Table 34 and Figure 50).
Table 34 Cockburn ( Rottnest) cooling energy increase (SSP3-7.0)
Cooling energy (MJ pa)
Present 2050 2080 increase increase
Jan 3,949 2,809 5,438
Feb 5,167 1,905 4,518
Mar 3,554 1,769 4,135
Apr 1,217 897 1,715
May 533 603 1,073
Jun 85 40 85
Jul 116 89 118
Aug 211 60 95
Sep 154 110 201
Oct 414 246 848
Nov 827 720 1,682
Dec 4,354 1,827 4,254 20,581 11,076 24,161 54% 117%
50 Cockburn (Rottnest) - cool ing energy (SSP3-7.0)
Heating energy demand will decrease by around 15% by 2080 under SSP3- 7.0 (Table 35 and Figure 51).
Table 35 Cockburn ( Rottnest) heating energy decrease (SSP3-7.0)
Heating energy (MJ pa)
Present 2050 2080 decrease decrease
Jan 536 243 437
Feb 142 19 36
Mar 562 75 473
Apr 624 219 387
May 970 408 437
Jun 859 152 -56
Jul 798 58 123
Aug 364 -480 -1,018
Sep 671 -300 -519
Oct 1,037 9 408
Nov 726 9 107
Dec 607 98 347 7,897 511 1,163 6% 15%
Figure 51 Cockburn (Rottnest) - heating energy (SSP3-7.0)
Figure
5. Summary and conclusions
5.1 Unconditioned performance of the traditional houses
The annual percentage of hours in which the indoor air temperatures are projected to exceed the cooling setpoint increases in all cases (Figure 52) although the magnitude of change varies. In summer, Broome and Karratha are already at 90-100%, so the annual changes represent increasing temperatures in the shoulder seasons. The largest changes occur in Geraldton and the Perth coastal locations where exceedances will approximately double from present conditions. In Toodyay and the Perth central and eastern locations exceedances will increase by around half. This poor performance of unconditioned houses is particularly worrying for social housing and vulnerable families that do not have the benefit of air-conditioning.
The annual percentage of hours in which the indoor air temperatures are projected to fall below the heating setpoint will decline, noting that heating is not required in Broome and Karratha. Elsewhere the magnitude of change will be 40-60% (Figure 53).
52
53 Annual unmet heating hours
It is important to note that these projections are only to 2080 for the selected scenarios. Global temperatures for these scenarios are projected to increase well beyond 2100, particularly for SSP37.0. Accordingly, unmet hours will likely increase beyond the results reported here unless urgent action is taken to eliminate emissions.
5.2 Conditioned performance
As noted in the Phase 1 report, c ooling loads in the south of the state are less than half that in Broome and Karratha but exhibit no significant differences between traditional and new houses on a per m2 basis. The results broadly reflect latitude, but with the coastal influence observable in Geraldton and Perth.
The new house design (Rottnest St) represented in the southern region case studies is around the average size of new housing in Perth at 206m2 (conditioned area) compared to the traditional house (Upton St) which is 67m2 conditioned area. Accordingly, the total cooling energy is proportionally higher.
Cooling energy demands are projected to increase substantially in all locations (Figure 54), by 20% by 2050 and 70% by 2080 in Broome and Karratha, and 30-70% by 2050 elsewhere. Cooling energy
Figure
Annual unmet cooling hours
Figure
demand is projected to increase by 80-160% in Geraldton, Toodyay and the Perth precincts (Figure 55.
Figure 54 Cooling energy - traditional houses
Figure 55 Changes in cooling energy demandtraditional houses
Heating energy demand is projected to decrease in the southern locations in both newer and older houses (Figure 56 and Figure 57), although not by as much as cooling demand will increase.
Figure 56 Annual heating energy – traditional houses
Total energy required to condition (i.e. cool and heat) houses is projected to increase by around 1724 GJ pa in Broome; 13-19 GJ pa in Karratha; 12-31 GJ pa in Geraldton; and 7-23 GJ pa in the other locations, with older houses seeing the largest likely increase.
It is important to note that these projections are only to 2080 for the selected scenarios. Global temperatures for these scenarios are projected to increase well beyond 2100, particularly for SSP37.0. Accordingly, energy demand will likely increase beyond the results reported here unless urgent action is taken to eliminate emissions.
5.3 Electricity demand
The Phase 1 report includes a comparison between energy predictions of the models with actual electricity data for the Broome and Perth case studies. Assuming loads other than cooling and heating remain constant, the average impact of climate change on overall electricity demand can be approximately estimated.
Figure 58 and Figure 59 are illustrative only of the likely increases over the coming decades. Substantial increases are likely in the north of the state in older houses, but mostly after 2050. Smaller increases are likely in better performing new houses of similar size. In Geraldton smaller and older houses will likely see increases of around 15% by 2080 but higher increases in larger, newer houses. In Toodyay and Perth electricity demand will likely increase by 5-10% in older houses and 10-20% in newer, larger houses in coming decades. As global temperatures for these scenarios are projected to increase well beyond 2100, electricity demand will likely increase beyond the results reported here unless urgent action is taken to eliminate emissions.
Figure 58 Projected electricity demand - old houses
Figure 59 Projected electricity demand - new houses
6. Next steps
In the next phase of the research the research team will develop and evaluate the performance of design proposals to adapt the housing case studies to projected climate change. This work will be informed by a survey of experts in combination with a review of the relevant literature.
Adaption of existing housing is challenging for a range of reasons:
• the options to physically modify existing houses are limited (e.g. insulation, improved airtightness);
• the sheer scale of the retrofit task across the state would be immense; and
• the costs of effective retrofitting will be substantial and unlikely to be offset by energy savings alone.
It is likely that in newer air-conditioned houses the response to climate change will be an increase in energy consumption. In the much larger stock of existing houses, many without air-conditioning, retrofit options will be the focus. The research will determine whether retrofits can be sufficient to create acceptable levels of thermal comfort in these houses.
7. References
Chen, D. (2016). AccuRate and the Chenath engine for residential house energy rating. Retrieved from https://www.hstar.com.au/Chenath/AccuRateChenathRepository.htm EnergyPlus. (2024). EnergyPlus. Retrieved from https://energyplus.net/ IPCC. (2023). Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change In IPCC (Ed.). Geneva: International Panel on Climate Change. Rodrigues, E., Fernandes, M. S., & Carvalho, D. (2023). Future weather generator for building performance research: An open-source morphing tool and an application. Building and Environment, 233, 110104. 10.1016/j.buildenv.2023.110104
