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Nortonman
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Join Date: Sep 2013
Posts: 16

River Current Power

09/03/2013 4:19 PM

I live on a river with a 25 foot deep Chanel that flows about 6-7 mph. It over 65 ft wide. I'm looking for an underwater unit to develop electricity,with minimal disruption to the environment . A proper screening unit,while not restricting flow ,can accomplish this. I need a starting place to purchase a small underwater unit to start my data,plan,ect... Little help anyone? Thanks much!
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SolarEagle
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Join Date: Mar 2007
Location: by the beach in Florida
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#1

Re: River current power

09/03/2013 4:32 PM

I have just the thing....

http://gizmodo.com/5967882/drop-this-underwater-turbine-in-any-river-for-free-continuous-power

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lyn
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Join Date: Oct 2008
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#2

Re: River Current Power

09/03/2013 4:53 PM

There once was a guy who can here saying he could "save the world" by putting barges in rivers to generate power. He was a lunatic.

SE's link has merit.

Depending on where it is located, there may be waterway restrictions on such devices.

Sounds worth pursuing.
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Nortonman
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Join Date: Sep 2013
Posts: 16
#3
In reply to #2

Re: River Current Power

09/03/2013 5:48 PM

Thank you ,Lyn. I've been looking and think I will try small then increase the ratio per scale. I appreciate the input. Be well,Eric
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lyn
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#4
In reply to #3

Re: River Current Power

09/03/2013 5:58 PM

Small-scale Water Current Turbines for River Applications - Zero
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PWSlack
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United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

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Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on.
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#5

Re: River Current Power

09/04/2013 3:24 AM

In the UK, one would need a licence from the Environment Agency before installing such a device, a Planning Application from the Local Authority, and consent from the Admiralty too.

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dieselphil
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Join Date: Jul 2008
Location: Glos, England
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#6

Re: River Current Power

09/04/2013 3:47 AM

Hi, although I am sure a small-scale (ie <5kW) unit may very well work, to get any significant power needs some kind of barrage to maintain a head difference - just think about it for a minute ..... you cannot extract the (small amount anyway) of kinetic energy, as water is incompressible, so its inflow velocity has to be equal to its outflow velocity .....therefore power can only be generated by a head (= pressure) difference from upstream to downstream side.

A small unit will achieve this by (very locally) slowing the flow at the entry, thus raising the level slightly, and the outlet will see a lower pressure because of the (slightly higher) velocity of the water flowing around it.

To extract more power a different technique for creating a difference in water level must be used - conventionally called a dam or barrage.

If you use a large number of small-scale units together they will create their own head difference, by in effect becoming a barrage.

The physics is straightforward, but it's amazing how many people get hoodwinked!

There was a scheme to do just what you are proposing on the river in Hull, England at a place called "The Deep" (an aquarium) - several businessmen got drawn in, and lost many many thousands of pounds (I think close to a million) because someone hadn't done their thinking correctly at the beginning and then compounded the error by building a small-scale rig that didn't bother to record the head difference inlet - outlet!

So, sure, get yourself a little free power if you can, but don't expect to get any more without all the big civil engineering that goes with a "proper" hydro-electric scheme.

Best regards,

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Lynn.Wallace
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Join Date: Dec 2009
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#7
In reply to #6

Re: River Current Power

09/04/2013 11:42 AM

Sounds like a water wheel is what's needed, then. (Is that the right line of thought?)

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Nortonman
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Join Date: Sep 2013
Posts: 16
#9
In reply to #7

Re: River Current Power

09/05/2013 8:42 AM

One 1600 ft home,with LED lighting,proper power usage,I believe that a small under water unit turning a shaft,sent to a gearbox shed,( all done through proper small scale models) can achieve intended purpose. Energy can be transferred,perpetual current,flow rate scales,charts ,research,.no it's not easy,but worth doing to stay warm,read a book,power small efficient appliance units . I have seen floating inner tubes in China,powering a home with one light bulb! The math can be worked out for the flow/ scour/ physics/ crowd. But to not try? Positive V. Negative. I live in America,where anything is possible. But Middle East Peace!! The longest journey starts with the first step.
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AussieBob
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#10
In reply to #9

Re: River Current Power

09/11/2013 9:02 PM

This one is interesting, may not suit your 65' river and probably better suited for an incoming local stream. An ideal solution for low head, low flow irrigation applications but does have some small power output possibilities

http://www.ebengineering.co.nz/solutions/turbine
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1capybara
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Engineering Fields - Electrical Engineering - New Member Engineering Fields - Power Engineering - New Member

Join Date: Mar 2012
Location: the sandbox
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#8

Re: River Current Power

09/05/2013 3:10 AM

check out lyn's link. 5kw of free power is gr8. its enough to run 5+ houses. WOW!

if i lived on a river i'd do it. just plan what to do about boulders rolling downstream, logs floating downstream, and winter ice.

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1capybara (1); AussieBob (1); dieselphil (1); lyn (2); Lynn.Wallace (1); Nortonman (2); PWSlack (1); SolarEagle (1)

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