2. How to be Cool Mike Dennis Department of Engineering

3. How do we get “Cool”

4. Air Conditioning Condensor Evaporator 2 kW Compressor Electricity consumed here 35°C Expansion valve 8°C

5. Now you’re cool, but expensive 2/3 of all houses in Australia have air conditioners Big energy consumers! Peak loading on electricity grids $ 30b required to upgrade grids over the next 20 years $

6. Don’t be silly…

7. Greenhouse Neutral House Houses as distributed power stations

8. Solar Air Conditioning Condensor Evaporator 2 kW Compressor Electricity consumed here 35°C Expansion valve 8°C

9. Photovoltaic Air Conditioning Condensor Evaporator Hot Side Cold Side NPNPNP ExpansionCompression Vapour Compression Peltier Cell Stirling Cycle

10. Thermal Air Conditioning Condensor Evaporator Abs Gen Condensor Evaporator Absorption cooling Adsorption cooling Dessicant / Evaporative cooling

11. Thermal Air Conditioning Condensor Evaporator Condensor Evaporator Ejector Cycle Organic Rankine Cycle

12. The Ejector Cycle Ejector heat pump Condensor Evaporator Condensor Evaporator Conventional heat pump 8°C 35°C 1kW COP = 3 35°C 8°C 0.1kW 16m 2 COP e = 0.7, COP m = 30 90°C

13. Condensor Cool, warm and wet Evaporator Winter space heating Water heating One system High solar contribution Three energy services

14. Leveraged Operation Intercooler Condensor Intercooler Evaporator 8°C 0.4kW 20°C 35°C 0.1kW 90°C Reduced electricity consumption Increased cooling effect Smaller collector *** Retro-fit solution and night operation possible ***

15. The Ejector (compressor) Solar heated primary Sonic shock Need high secondary flow Need high compression ratio Evaporator seondary

16. Ejector thermal compressor Solar fluid nozzle Vacuum port Mixing Chamber Diffuser Inside the solar nozzle

17. Sensitivity

18. Progress to Date This work is supported by the Faculty Research Grant Scheme (FRGS)

19. Research Directions Improved flexibility Variable geometry ejector Smart control and actuation strategies Improved cogeneration and integral thermal storage Improved performance Dynamic optimisation of coupled operation Liquid pressure amplification Improved CFD models Mixing phenomena