Dong Chen and Xiaoming Wang

1. Potential Challenges for the Built Environment in Northern Australia Dong Chen and Xiaoming Wang

2. The Global Warming We Are FacingMelbourne Bushfire 7Th February 2009 On 7th February 2009, reaches 46.4oC, the hottest ever recorded in Melbourne. The deadliest bushfire in Australian history, killed 173 peoples, destroyed and damaged 3000 houses. Adaptation Engineering

3. The Global Warming We Are FacingBrisbane Floods 2011 The floods inundated about 30,000 homes and businesses in Australia’s third largest city. The cost to the nation may total as much as AUS$13 billion. Adaptation Engineering

4. The Global Warming We Are FacingClimate CommissionReport May 2011 This year's Queensland and Victorian flooding “raised the question of a possible link between the floods and human-induced climate change'' Based on observations and various events “ the impacts of climate change are already being felt in Australia and elsewhere…” ''Minimising these risks requires rapid, deep and ongoing reductions to global greenhouse gas emissions. We must begin now if we are to decarbonise our economy and move to clean energy sources by 2050.'' Adaptation Engineering

5. Australian Residential Sector – the Challenge Source: National Inventory by Economic Sector 2006, Department of Climate Change, Canberra

6. Australian Residential Sector – the Challenge Australia’s 5% and 80% GHG emission reduction targets in 2020 and 2050 respectively from the 2000 level requires dramatic GHG emissions reduction in all sectors

7. Climate Change and Buildings Climate CO2 Temperature Humidity Solar Radiation Wind

8. Climate Change Impact Simulation TMY Weather Data Future TMY Weather Data Climate Models Star band Total Heating and Cooling Loads per m2 (MJ/m2) Assumed Occupants Behaviours AccuRate Engine Building Physical Data with Rules Star Rating

9. Projection of Climate Change T RH

10. Projected Ambient Temperature for Darwin Hours above 35oC Present ~ 5h 1oC ~ 50h 2oC ~ 200h 3oC ~ 500h

11. An Example House for Simulation Studies • Floor area 160 m2 • Net air-conditioned floor area 140 m2 • Four bedrooms • Brick veneer house

12. An Example House for Simulation Studies Floor area 160 m2 Net air-conditioned floor area 140 m2 Four bedrooms Brick veneer house

13. Climate Zones in Australia

14. Effect of Global Warming on House Heating and Cooling Carbon Emission In comparison with other major cities, cooling energy consumption is projected to significantly increase in Darwin and Alice Springs.

15. Impact on Cooling Demand in Darwin Energy efficient houses are predicted to out-perform inefficient houses for energy saving and GHG emissions reduction Demand Increase at 2 oC Global warming 2 star 440 MJ/m2/yr 65% 5 star 295 MJ/m2/yr 69% 7 star 185 MJ/m2/yr 63%

16. Impact on Indoor Air Temperature Air temperature above 35 oC Global warming 0oC 1 star 30 hours 2 stars 19 hours 5 stars 0 hour 7 stars 0 hour

17. Impact on Indoor Air Temperature Air temperature above 35 oC Global warming 2oC 1 star 400 hours 2 stars 345 hours 5 stars 10 hours 7 stars 0 hour

18. Impact on Indoor Heat Stress Index Discomfort Index >28 Global warming 2oC 1 star 4345 hours 2 stars 4280 hours 5 stars 4339 hours 7 stars 4167 hours Energy efficient houses are predicted to out-perform inefficient houses for indoor thermal comfort and heat stress. However, its protection to global warming is limited.

19. Heavy Weight or Light Weight Elevated lightweight ? Double brick with slab-on-ground ?

20. Heavy vs light – Cooling Demand Light, medium, heavy weight houses may have similar performance in terms of cooling energy requirement with 2 to 3 oC global warming.

21. Heavy vs light – Indoor Temperature Air temperature above 35 oC Global warming 0oC 1 star BV 30 hours 1 star L 32 hours 1 star H 0 hour 7 star BV 0 hour 7 star L 2 hour 7 star H 0 hour

22. Heavy vs light – Indoor Temperature Air temperature above 35 oC Global warming 2oC 1 star BV 400 hours 1 star L 424 hours 1 star H 127 hour 7 star BV 0 hour 7 star L 128 hour 7 star H 0 hour Heavy weight houses may out-perform light weight houses in reducing extreme indoor air temperature

23. Development of High Energy Performance Residential Buildings AUS-ZEH

24. Potential energy demand & GHG emissions reduction of a typical house in Melbourne – now!

25. Reduction potential in Five Australian cities ~48% average 61-81%

26. Pathways of Climate Adaptation for Buildings Adaptation Pathway Impact Electrical Appliance Efficiency ① Building Energy Efficiency ② Darwin Ren ZG, Wang X, and Chen D, (2011). Working in progress.

27. Cost-Effectiveness of Adaptations for Buildings – A 6oC Global Warming Scenario • Cost-effectiveness of each adaptation options depends on locations. • Adaptation options more expansive in Sydney and Brisbane than in Darwin ($/kWh). Darwin Cost per kWh reduction Average cost per kWh reduction Increase in energy consumption due to climate change Reduction in energy consumption due to adaptation Sydney Brisbane Ren ZG, Wang X, and Chen D, (2011). Working in progress.

28. Minimising global warming risks requires rapid, deep and ongoing reductions to global greenhouse gas emissions. Darwin and Alice Springs is projected to increase cooling energy significantly under global warming; Energy efficient houses out-perform in energy saving and GHG emissions reduction; Energy efficient houses out-perform in indoor thermal comfort and heat stress. However, its protection to global warming is limited Conclusions

29. Conclusions (continued) Light, medium, heavy weight houses may have similar performance in cooling energy requirement Heavy weight houses may out-perform light weight houses in reducing extreme indoor air temperature Cost-effectiveness of adaptation options depends on locations. Adaptation options more expansive in Sydney and Brisbane than in Darwin in $/kWh

30. Thank you Contact: Dr Dong Chen CSIRO Sustainable Ecosystems Po Box 56, Highett, Vic 3190 P: 03 9252 6056 E: Dong.Chen@csiro.au Web: www.csiro.au Contact Us Phone: 1300 363 400 or +61 3 9545 2176 Email: enquiries@csiro.au Web: www.csiro.au