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Power Usage

  1. Feb 12, 2009 #1

    DavidSnider

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    Is it better to leave the heater going constantly or turn it off when you leave the house?

    I've heard people tell me that it takes more energy to bring it back up to temperature every day than it does to just leave it running all day. That doesn't seem intuitive to me.. is it true?
     
  2. jcsd
  3. Feb 12, 2009 #2
    It saves energy and money to turn it down, because the rate at which heat is conducted through the walls from indoors to outdoors is proportional to the temperature difference between indoors and outdoors. An amount of time that it's cooler inside will be an amount of time during which the rate of the loss of heat will be slower.
     
  4. Feb 12, 2009 #3
    It may save money to keep it on. At peak times of day, the energy grid has to turn on their most expensive and inefficient generators, and so raising the temperature with peak electricity tends to cost more than using extra off-peak electricity to avoid this. But home electricity meters often do not account for any price fluctuations.
     
  5. Feb 12, 2009 #4
    It's a good question, and in my opinion the answer can be very different with different circumstances. So I think it's important to first ascertain your specific circumstances and then adjust how you use your heat.

    For example, if you live alone, are gone for 12 out of 24 hours, it's above freezing, your home is "reasonably" insulated and takes only 15-20 minutes to heat your home to 68... then it might be extremely wasteful to leave the heat on at 68(or whatever) for the 12-hours your away from home.

    Of couse, in any circumstance, one should keep the thermostat at least 5-10 degree's above freezing at all times.
     
    Last edited: Feb 12, 2009
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