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There are a couple of things we have to investigate to get our water wheel up and running. Intro First of all, there are a couple of different kind of wheels: From a post from usenet: There are three primary classic forms of waterwheel, the overshot
wheel, the undershot wheel, and the flow of stream paddlewheel.
None of them are very well suited to electricity generation. The
better solution for micro-hydroelectric systems is the small high
speed turbine utilizing a fall via a headpipe. The turbine for a
5-10 kW system is roughly 5-12 inches in diameter, and manpackable.
Unless the fall is extreme enough to require steel pipe, the piping
can be PVC, concrete, or clay.
If you can't arrange on the order of 50 feet of fall, however, you
may need to go with one of the classic waterwheels. An overshot
wheel requires a fall on the order of the height of the wheel. An
undershot wheel can function with a lesser fall, and a flow of
stream paddlewheel requires very little fall. However, the amount
of energy available is proportional to fall and flow, with fall
being the more critical parameter for good economy. Slow wheels
are generally less efficient (with flow of stream paddlewheels
the worst offenders), and require belts or gearing to increase their
shaft speed to the 1800 RPM required by the generator. It's better
to avoid those, often considerable, mechanical losses if possible.
So, the first thing you have to do is do a hydropower survey of
the site. You need to establish the maximum practical fall that
can be tapped, and the average stream flow available for use.
That will determine the best form of waterwheel to use. Such
a survey is simple, requiring only a watch with a second hand
and a stick float to time stream flow, a level (can be fabricated
on site from some plastic tubing and local water) to determine
fall, and sticks and string can be used to survey the streambed
to figure the cross sectional area for volume calculations, and to
do the actual surveying of the site.
If sufficient stream capacity exists to supply your power requirement,
then you should directly generate 110 VAC (or 220 VAC) rather than
attempting to generate DC and put it through power conversion electronics.
AC generators are robust, and don't require the sophisticated troubleshooting
skills and imported electronic parts of inverters to maintain. For a turbine
system, a mechanical governor operating a valve in the headpipe will maintain
proper frequency. For slow wheels, some form of mechanical transmission and
weir gates operated by levers will be required, and regulation may be poor
under varying load.
Gary
This basically described what we need for hydro electricity which is not what we're aiming at for the moment. Type We're looking at using the water power to pump water up. So we are going to use a flow of stream paddle wheel. We need to measure the speed of the water passing through our stream at different times of year/season. At the moment, the river is very low, so it's a good indication to see what the minimum stream power is we're going to get. We basically have to measure the time it takes for a stick to travel over let's say a 20 meter distance. Building The second thing we need to figure out is how to build the wheel. The wheel
Will we use wood, metal, aluminium, plastic? Plastic would probably be the best but we need to make a model in some other material to make a mould. So it's probably going to be wood or metal to start with. Connections
We need to have a mechanical seal. Some kind of seal which connects the rotating shaft (which is the axle of the wheel) to a fixed shaft which is put on land and guides the water into a container at 10m height. These seals are probably the most difficult part to find. There are some quick hacks we can use like metal garden hose connectors but the friction is a bit too much for smooth operation and also they probably won't last long. The best thing would be to have proper seals but to make them ourselves requires some handy work which will very interesting to do but take some time. To be continued.
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Suj did it!!
