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Mini HydroPowered Generator..free power!? Answered

Hello Instructables Community!

I am planning to build a small HydroElectric plant in the stream behind my house. After years of all that potential power flowing by, I want to do something about it! I know the specifics of using turbines and such, but what I can not figure out is how to use this power! Should I simply wire it into my house somewhere (a special plug), or should I try to do something like store it in powerful rechargeable batteries? One of my relatives gets free Natural gas from a well on his property, and being the wizz he is, modified a generator to turn this gas into electricity and he even has excess electricity to sell back to the power company! That would be a luxury to have, but I know I'd need a lot of water for that amount of power, heh.

I'm usually pretty creative, but I'm lacking right now! After searching for a couple hours on the web, I thought I'd see if you guys could help me out.




7 years ago

I have a 6 foot high by 20 foot wide dam.
the dam has a 4 inch valve at the base.
I want to put in 1 or 2 Hydros on the stream.
the stream will fill a 5 gallon bucket in 2 minutes during the dry months.
the dam is 170 feet above the House. used a GPS to measure the Height differance.
where can i buy pre-made Hydro kits. New or used.

It depends, as Kiteman said, on how much power you can actually get from your mini-hydro. If you only get a kilowatt or so, it's not going to do you much good, except as a learning exercise :-)

I know there are good, functional systems out there; I'll try to have a go at doing a search myself, since you were unsuccessful.

How you hook it up is your option. If you want to use it just as "internal power," then look up how to connect an emergency generator to your house. The philosophy is the same, as are the safety issues.

If you want to use it like a solar power system, and put the excess power you don't use back onto the grid, then be prepared to spend a few thousand dollars. A "grid inverter" must be installed professionally, and it's expensive because actual lives are at stake. The device does two things: it matches the phase of your generated power to the phase of the mains, and it shuts off the outgoing power when the mains are down. That latter is critical; if you are putting power onto the main power lines while a utility crew is trying service them, you are going to kill someone.

Sounds like a great project, so good luck!

Yeah, I wasn't really planning on doing anything that big, it would just be neat to have as an emergency generator providing it gives enough power (which it would give a fair amount, as the stream is very fast moving, about 2ft deep, and is fed by a spring about 1000 feet up the valley) I'd likely go with charging a bank of batteries.

Of course, it is relative to what you use. A kilowatt continuous would nearly halve my power bill.

Can you  tap the stream further-up, how much head can you get?


It depends on how reliable the stream is, and how much power you can tap from it.

Most likely, you'll need to charge a bank of batteries, and run appliances off the batteries as required.

I'll have plenty of power from the stream as i commented above, and I'll go with your idea using a bank of batteries.

There is one non-electrical issue to keep in mind, and that is water rights. Do you have water rights to the stream? There should be a clause in your property deed (or in the CC&R) spelling that out. If you do have water rights, then you can install the generator, but you must make sure that you don't pollute the water for downstream users. If you don't have water rights, then you would have to secure an easement from the owner of those rights do put in the generator.

Oh yes, I own all of the water rights for several acres. I live back in the country a fair bit :P.