Brain storming back up power

[plantwomyn@verizon.net]

I've read here and on Backyardaquaponics about the back up systems ya'll have. Murray suggests battery back up here and there. I read in a tread about the pelton water wheel. I won't have a stream or water fall but the pumps will be going and the water will be circulating.
So... what if you put a small water wheel generator at the return pipe? It would have to be small enough to turn with the minimum flow but it could keep your batteries charged every day. I've looked around and seen some homemade wheels that are small but as I'm no engineer or electrician don't know if it would work. I think it would be like a trickle charge system.
Can anyone with a spot of knowledge in electricity give me an idea if a very small water wheel could manage to charge a 12v battery?

[GaryD]

Hi,

The little water wheel idea seems fine in theory but the reality is that you'd be better off with a small trickle charger to keep your battery topped up.

I understand (and support) the idea of energy conservation, however, the water and air pumps using in aquaponics as so small and draw such a small amount of power that they pale into insignificance against the likes of an air conditioner, refrigerator or most other household appliances.

The goal of a backup system is to keep dissolved oxygen in your system pending the restoration of power supplies or the replacement of a failed pump......probably for a maximum of six or so hours.

Night time failure of pumps or power supply is the biggest risk you'll face but a 12 volt backup system will get you over that hurdle nicely.

Gary