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The human body as a radiator - Air conditioning

  1. Feb 20, 2007 #1
    After reading the thread "how many watts does the human body use?"

    I calculated that my body requires 86 W of energy on average throughout the day.

    However, I am wondering how much excess energy my body radiates as waste heat (and blackbody radiation) ? Obviously this depends on a lot of variables--body mass, pulse rate, rate of expenditure of physical energy, how much caffeine is in my body (causes blood vessels to dilate), energy of the Kcalories that have been eaten (as opposed to the
    Kcalories my body actually needs), state of consciousness, etc.

    I am just interested in a rule-of-thumb that people who design air conditioning systems use for waste heat dumped by people, awake and sleeping.
  2. jcsd
  3. Feb 20, 2007 #2


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    Staff: Mentor

    You've accounted for all of it. All of the energy we produce by burning food gets radiated (or convected) away as heat.

    And your number sounds about right.
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