1. Objective Address your concerns/suggestions Review Learn about Cooling Systems Compressor cooling circles Sorption coiling Evaporative cooling

2. Vapor Compression Cycle Expansion valve Outdoor 105°FIndoor 75°F

3. Thermodynamics - review

5. Enthalpy: h [J/kg, Btu/lb] Temperature change ΔT Δh = c p ΔT – only for the same phase (air, water) What if we have change of the phase -evaporation or condensation? Entropy: s [J/kgK, Btu/lb°F] Δh = T Δs for evaporation or condensation

6. What is the COP? A.Congressional Observer Publications B.California Offset Printers, Inc C.Coefficient of Performance D.Slang for a policeman

7. COP Coefficient of Performance

8. Refrigeration Cycle

9. Components of a DX system Compressor Evaporator Condenser Expansion valve

10. 92 °F 56 °F 69 psig DB = 77 °F WB = 64 °F orifice capillary tube TXV 110 °F ~200 psig DB = 60 °F WB = 53 °F High pressure, high boiling/condensing point Low pressure, low boiling point DX Cooling Machine

11. Air Cooled Chiller Outside air 95°F Inside 75°F Water 42°F Building Water 52°F Chiller

12. Water Cooled Chiller Outside air 95°F Inside 75°F Water 42°F Building Water 52°FWater 120°F Water 100°F Cooling tower Chiller

13. Cooling Evaporative cooling Compressor Cooling Sorption cooling DX machine Chiller Air Cooled Condenser Water Cooled Condenser Convert Cooling machine (DX machine) to heat pumps Evaporative Chiller

14. Air cooled condenser Only for small capacity Cool the water or directly the refrigerant for compressor chillers

15. Cooling tower Provide cooling water for condenser or absorption Type Location Legionella

16. Evaporative Cooling Wet media/water spray – direct Raise absolute humidity, lowers temperature of conditioned air Cooling tower – indirect Cools through a heat exchanger Lowers temperature, does not affect absolute humidity Can directly cool air in cold weather

17. Evaporative Cooling

18. What is Heat Pump ? Cooling Heating Outside 95°F Outside 55°F Inside 75°F

19. www.srpnet.com/energy/pumpworks.aspx 1) Compressor 2) Condenser 3) Evaporator 4) Air handler 5) Reversing valve and expansion valve

20. COP for heat pump

21. Energy Storage Systems

22. Daily distribution of cooling load

23. Thermal Storage Make ice/chilled water at times of low demand or low energy prices Store water in insulated container Can be used to reduce overall demand Water can be used as secondary water source for fire protection Ice/snow

24. Thermal Storage

25. Reading Assignment Tao and Janis Chapter 4