small Hydro on a major river

[jflint5429]

I am interested in a small hydro generating setup on a major river, portable of course

Obviously I can not make any changes to the river, I just want to put a generator near the shore, and produce what power I can

a propeller based generator is my first thought, the only way I found to not have head and still generate power, but I am not sure that is practical overall for home fabrication

I have searched the web for a few days now, but can't really find any info on generating power in a river, without modifying the river

could a generator like the ones built on this site be used to generate power from the river?

basically a windmill design with a lot more very short blades, each 90 degrees to the water, the speed would be a little slower then windmill, so the design of the generator would probably change

Looking for information and advice

Thanks

[Phssthpok]

A larger undershoot paddlewheel would not alter the river in any way and, depending on overall diameter, could provide PLENTY of Torque to use a belt or chain drive setup to gain rotor speed. Just a first thought idea.

Alternatively, if you have oodles of money to throw at the project you could build, say, a 15' diameter waterwheel with magnets on the perimeter, and a 15' stator to match!

[Countryboy]

To obtain power from hydro, you need one of two things.  You either need flow, or you need head.  By being unable to modify the river, you are stuck with near zero head.  That means you have to have sufficient flow.  Flow is greatly reduced near the shore.

In essence, you don't have much to work with.

I would forget trying to use the submerged windmill like you proposed.  The windmills aren't designed for underwater applications.  Submerging in water is a good way to short everything out.

I've seen DC trolling motors used as hydro generators.  However, they typically have to be in a pretty good current before they produce usable power that way.

If I were you, I'd try to find a cheap trolling motor.  Take off the regular propeller, and mount box fan blades on it so you get a larger swept area.  You may need to gear up the DC motor so you get sufficient RPM's to generate a usable current.  See how that works out, and then decide if you want to bother with a more elaborate set-up.

[elvin1949]

How about an outboard lower unit with box fan blades

 Has about a 1.5 to 1 gear up.Put gennie on top.

later

elvin

[wdyasq]

Check out the Gorlov Turbine. I think it is what you are looking for.

Ron

[mikey ny]

     Just a thought about DC trolling motors. Could they be used with a large water wheel? or even maybe with a prop for a small wind generator? Most of them have several speeds.

[RogerAS]

j,

Several yeas ago I saw a device on TV that used the temperature differintal of the water/air to drive a coolant based system. He in-lined a small turbine to capture the refrigerant motion energy. It lit a 100W standard light bulb quite brightly. I never knew what became of it, and I have no clue how to track it. It used no compressor. It was shown on local news Eugene, OR in about '83-'85. One set of coils were floating in the Willamette river, a set of automotive flex hoses to shore (5') and a big ass set of coils in the air. A turbine in the lines between coils. I think it was double acting using both sides to get power.

I imagine the possibility of leaking freon & associatted chemicals into the water is what killed that idea. However I think it might work with a different medium like helium, propane, hydrogen as the main coolant fluid. Something begnin to the environment in the event of failure to contain. One wouldn't need much flow with a big absorbtion turbine and exchange system. Massive refrigeration as a byproduct might be possible. Any fluid dynatics geeks awake out there?

Just how big is the river flowing by? The Colombia? The Mossouri, The Snake.... How big is big?

If you have permission to anchor an undershot on a flexline to allow for rise and fall, one could get some power that way. Set it upstream, and close to the "whirlies" that show obvious water motion. Make it with adjustable depth of draft on the paddles for a govenor. Have wings that funnel more water into the wheel zone. Make the pontoons, or other floatation, super durrable. Run it deeper to get even more torque. There's a lot of if's in a row needed to make power this way. IF one could string together 20, 30, or more of these down a long straight line it would have to add up. Irrigation canals should do this or something else to get that power back instead of just letting it waste. Opps, sorry, got to thinking of conservation of power there. :-)

Good luck oh yee most blessed with water. I live on a rock pile/hardwood forst/south side of an Arkansas mountain. I could build some water diversion ditches and carve up the side of my considerable incline to gain head with very limited flow. That would only happen occasionally so I can't see it high on my list. I dream of some water flow!

[badmoonryzn]

Hey Roger,

I assume you livenear me as I live outside of Cottage Grove and have the Row river running through our property. I want to put up Solar, wind and water to get meoff the grid. I was wondering if you know the laws governing an undershot wheel. I have the best flow for miles in my back yard as the river narrows and has deep channels with several sets of rapids. I have tubed this river many times and we have the fastest water I have seen, however it is a flood controlled river so I would have to employ a device that would allow for 7 to 10 of winter high waters. Any help would be great as I had to fight to keep our water rights, but I am unclear on what I can do without diverting.

Regards,

Badmoonryzn/Dennis