What about an old refrigerator?

You would NOTwant to pay the electric bill for running that refrigerator.

A refrigerator's compressor/condensor system is not exceptionally efficient in terms of power usage per BTU of heat extracted.

Just wire across the switch that controls your little 25 watt refrigerator light so it stays on all the time, and then see what happens to your electric bill. I guarantee it will be astonishingly more than 18 KW hours (25 watts times 24 hours times 30 days) a month!

tanstaafl.