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Old 01-23-2009, 04:05 PM   #14 (permalink)
wyatt
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Quote:
Originally Posted by Frank Lee View Post
The cat and I are heat emitting creatures. I wonder how much heat we normally put into the system? Also, use of lights add heat...
I found this calculation out there...

First, dietary calories are really kilocalories, so someone eating a 2,000 calorie diet is really eating 2,000,000 calories.

1 calorie is 4.184 joules, so multiply 2 million by 4.184 and you get 8,368,000 joules.

Divide that by seconds in a day, 86,400, and you get 96.85 watts.

We aren't really 100% efficient at turning food into heat, but we are somewhere on the scale of having a 100 watt light bulb turned on. I am sure a cat would be much less. Lights do add heat, but it's electric resistive heating which isn't the best way to go, so that shouldn't make a negative difference in your bill.
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