Solar battery storage

Old 11-09-15, 02:53 PM
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Solar battery storage

I'm looking to make a solar swamp cooler as a small project. The pump and fan for the device require 12 volts and a combined 800 milliamps. I want the system to be able to keep working however, if a cloud obstructs the sun or something of that sort. I was thinking I could do this by adding a battery pack in between the panels and the fan/pump. Unfortunately I don't know how to do that or whether I need something like a charge controller. Can anyone point me in the right direction as to what I would need to do for this part of the project?
Old 11-09-15, 03:04 PM
Tolyn Ironhand's Avatar
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Your cooler uses .8 amps @ 12 volts. Batteries are normally rated in amp hours. For example if you had a 10 amp hour battery your cooler could run 12.5 hours not counting any losses or embellishment of the battery rating by the manufacture. If you added a solar panel to the system it would have to be sized to be greater then what your cooler uses otherwise the system would not keep up.

The main reason you would need a controller would be to prevent overcharging or discharging the battery too much and damaging the battery.
Old 11-09-15, 03:42 PM
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Tolyn left you some great advice.

Your biggest concern is how much standby power you need.
We don't know where you live so we don't know how much sun you get per day.
We don't know how long you need backup power. For example.... does the system need to run all night long with no solar. What if it rains one day and there is no sun at all.

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