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Q & A: can batteries keep goats warm?

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Most recent answer: 02/28/2013
Q:
need heating at goat barn for kids; do not have electricity; is there such a thing as a battery powered heat lamp???
- donna (age 66)
glenwood, ar 71943
A:
In principle yes, you can run heat lamps or most other heaters off the dc voltage supplied by batteries. However, batteries don't store very much energy. A rather big 12V car battery might have a capacity of about 200 Amp-hours, which means only about 2.4 kW-hours of energy. A typical electric heater uses over a kW of power, so you could only run it for 2 hours on one battery. I guess if you bought 10 big car batteries, you could run about a day, and the 120 V you'd get if you put them in series would be just what a standard heater would need. Somehow this just doesn't sound practical.

There are alternatives. You could get a propane heater, so long as you're careful to vent it safely, etc. A propane tank holds a lot of energy. Or if you would feel more comfortable with just electric power inside, you could use a gas-powered generator just outside the barn. Again, a gas tank holds a lot of energy.

Maybe you could use a batch of solar cells to keep batteries recharged on sunny days. If you could get fancy (probably also not practical) you could use a heat pump ( a backwards air conditioner) to pump about five times as much energy in as you use from your battery. That might also require an inverter to convert battery power to ac.

You probably don't want to do what my roommates and I did in grad school- keep the goat in the house. It was ok with one goat (it was the most stable member of our group) but with several it could get unpleasant.

So you have a lot of options, but they're all a bit of a hassle and/or expense.

Mike W.

(published on 02/28/2013)

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