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Large scale hydroelectric power has been used worldwide for a long time to generate huge amounts of power from water stored behind massive dams.  Small scale hydropower has been used for hundreds of years for manufacturing, including milling grain, sawing logs and manufacturing cloth.  However, it can also be used without a dam to generate electricity for home scale remote power systems.  These so-called micro-hydro installations can be a very good complement to a solar power system, as they produce electricity 24 hours a day.

Waterwheels–It’s important to differentiate between water wheels and water turbines.  A water wheel is more akin the antique version we are all familiar with–a massive wooden wheel that slowly turns as the creek pours down over it.  Water wheels spin slowly, but with lots of torque. They are not particularly efficient, but can be very effective. Even a few watts of power coming 24/7 can help an off-grid power system immensely. There are only a couple of places specializing in water wheels and water wheel info, and both are excellent resources: The Waterwheel Factory and The Waterwheel Place. The latter also has a good waterwheel electrical output calculator HERE.

Scotty's Banki Turbine hydro plant

Scotty’s new homebrew hydro plant, using a Banki Turbine design built from scratch. The generator is a homebuilt permanent magnet alternator, very similar to our Brake disc alternators. In a Banki design, the water hits the vanes twice, once upon entrance and then again upon exit. There is only…

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