by windgat on Fri Nov 02, 2007 7:43 pm
Hi ariel. Water pressure is a way of storing energy, so to address the need you mention one approach is a small battery (just used for smoothing the power from gusty wind), and using a small circuit to turn on the pump when there is plenty of power, and off as soon as the battery gets towards flat. An overflow on the tanks would allow water to return to the source when the tanks are full (this absorbs extra power when there is a lot of wind, avoiding damage to the battery).
Alternatively, and perhaps better, you could omit the battery, and use a circuit to turn on a 'dump load'. The dump load is something like a heater, which absorbs any excess power. This means you will only have water pumped when the wind is blowing (good for the Western Cape where the water needs are greater in the South Easter seasons), so you will need a big tank (or tanks) to ensure you have water even when the wind doesn't blow for a few days.
In both scenarios, you could use mains power as a backup in case of low winds or generator maintenance (to either charge the battery or drive the pump directly).
Most important thing is to make sure you get a DC pump.
Hope that helps!
The question of incorporating the electricity into the domestic setup is quite a different subject belonging under the 'Electrics and controls' topic.