Chapter 5 part 2 Heat Pumps Refrigerators Air Conditioners Ground Source Geothermal Systems Efficiency of Heat Pumps Energy Efficient Buildings Countering

  • View
    213

  • Download
    0

Embed Size (px)

Transcript

  • Slide 1
  • Chapter 5 part 2 Heat Pumps Refrigerators Air Conditioners Ground Source Geothermal Systems Efficiency of Heat Pumps Energy Efficient Buildings Countering Sick Building Syndrome
  • Slide 2
  • Air Conditioner Layout
  • Slide 3
  • Home Heat Pump
  • Slide 4
  • Heat Pump Efficiency Efficiency = 100 * Thigh/(Thigh-Tlow) Where Thigh is the temperature of the high Temperature reservior in degrees Kelvin Tlow is the temperature of the low temperature Reservoir in degrees Kelvin As the temperature difference decreases, does A heat pump become more or less efficient? Can a heat pump efficiency exceed 100%?
  • Slide 5
  • Coefficient of Performance COP =heat transferred/electricty used =useful work/energy input why does COP change with the outdoor temperature?
  • Slide 6
  • Seasonal Performance Factor SPF= total energy output/total energy used How does SPF relate to the theoretical efficiency of a heat pump?
  • Slide 7
  • Relative Costs of Heating Methods
  • Slide 8
  • Ground Source Geothermal Pump
  • Slide 9
  • Slide 10
  • Tradeoffs of Ground Source More efficient (why?) Less peak power use (peak shaving) Why? BUT High initial cost for boreholes or trenches More than conventional heating/cooling Needs a superinsulated building to be economical In NY winters
  • Slide 11
  • Energy Efficient Office Building A-Interior Windows Funnel Light B-Fluorescent Lights C-Task Lighting D-Occupancy Sensors Low E Film Low Toxicity Materials Atrium More Insulation
  • Slide 12
  • Energy Efficient Office 2 1-Solar Panel 2-Hot Air Duct 3-Air Filter 4-Heater 5-Air Supply Pump 6-Circulation Duct 7-Outflow Duct 8-Exhaust Fan 9-Heat Exchanger
  • Slide 13
  • Energy Efficient Refrigerator (Vestfrost/Sunfrost)
  • Slide 14
  • Features of Vest Frost
  • Slide 15
  • Energy Efficiency of Typical Refrigerator We use about 500 KWH per month. Fridge is 15% of costs Our refrigerator uses 75 kWH per month or 2.25 kWH Per day or almost 3 times the usage of a vestfrost. Why?
  • Slide 16
  • Total Energy Usage Q/t = 1/R * A*delta T Where Q is heat loss per unit time t, R is average R value, A is surface area, And delta T is temperature difference. Qtotal = sum (A/R)*24*DD Where DD are the annual degree days R is the average R value, A is surface area Of house. Infiltration losses must be added to this.
  • Slide 17
  • Prevention of Sick Building Syndrome House plants can dramatically reduce the levels Of formaldehyde, benzene and trichloroethylene Within a home. Air inside a well insulated home Often 2 to 5 times more polluted than outdoor air. Some good ones Aloe vera (also good for burns) Bamboo palm Spider plant English ivy Janet Craig Warnecki dracaena
  • Slide 18
  • Chrysanthemum Same as the outdoor plants, Will also grow well indoors
  • Slide 19
  • Devils Ivy Grows well in Hanging pots Will tolerate neglect
  • Slide 20
  • African Daisy Needs to be started In a professional Greenhouse. Prefers warmer Climates.
  • Slide 21
  • Peace Lily One of the easiest Of large houseplants Grows well in low light Survives well at average House temperatures And humidity levels.