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Q & A: battery-powered heater

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Most recent answer: 12/17/2011
Q:
I always get cold when camping. I found a heated throw. I want to power it with an inverter connected to a good deep cycle battery. The heated throw use 115 watts... 120 volts ...60 hertz. How many hours or min can I have it on before the battery goes dead or gets too low? thank you.
- Marti (age 22)
vancouver, wa
A:
Your battery will have a certain amount of stored energy, maybe say 800 Watt-hours if it's a good-sized lead-acid battery. That could power the throw for about 7 hours, assuming that the inverter was completely efficient. You can also put the inverter somewhere so that you pick up its waste heat too.

On a big truck, you might be able to carry a small efficient heat pump, which could get you about 5 W-h of heat for every W-h of battery energy, unlike your throw.

Overall, if you want to carry a lot of energy in a light-weight package, fuels are much better than batteries. Batteries of course are better for things where you specifically need electricity, but that doesn't include all heaters.

Mike W.

(published on 12/16/2011)

Follow-Up #1: heat pump

Q:
thanks for the info.. never considered a sm heat pump
- marti (age 22)
Vancouver, WA
A:
welcome

(published on 12/17/2011)

Follow-up on this answer.