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I want a solar powered electric motor to turn my compost barrel How do I determine correct motor, solar panel, battery? Answered


I think you only turn the barrel infrequently don't you ? I'd use a windscreen(shield) wiper motor, or an electric window motor - get one from the local junkyard.

Mount a wheel on the motor that drives the outside of your drum - get rubber wheel from Lowes, home depot or where ever.

Now you need a simple timeswitch - preferably powered with its own batteries.

The battery and panel size depends a lot on how you want to run the thing. Can you put some times on it ?


wiper motor? not enough power. Wiper assemblies are only a few pounds. Tumblers can be hundreds of pounds. your gearing would have to be such that the tumbler spins at 1 rev/min or less depending upon the torque of the wiper motor.

The ones I've seen only rotate intermittently, so I stand by my statement. Wiper motor assemblies have a lot of torque. I have one here that can push at least 10Nm


a compost tumbler is heavy. solar panel? I don't think that will provide enough current. wire up a 1/2 hp 1725 rpm AC motor with 110 current and gear it down to spin 6-8 rev/min (probably two 16:1 gear reductions) and you're there. I suppose you could spin it a little faster, but I prefer mine to rotate about once every 10 seconds. I want to do the same for mine and that's what I've determined will work.