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coolEL
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Join Date: Sep 2012
Posts: 3

Airlift Powered Microhydro Turbine

09/06/2012 12:35 AM

In my exploration of airlift pump systems used to make an aquaculture system more efficient I came across a YouTube video of an experimental airlift system that moved an incredible amount of water. What's the thoughts on why this could or couldn't power a turbine. I'm thinking that the turbine could not provide enough power for the air pump to run. BUT.......small turbines these days pump out so much juice, it seems to make sense to me. Search Bouyancy Hydro on YouTube if anyone wants to discuss this.
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PWSlack
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#1

Re: Airlift powered microhydro turbine

09/06/2012 6:41 AM

So the proposal is for a turbine to be connected to the airlift system to provide the power to make the airlift system operate and drive the turbine - is this correct?

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coolEL
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Join Date: Sep 2012
Posts: 3
#2
In reply to #1

Re: Airlift powered microhydro turbine

09/06/2012 10:03 AM

Exactly, I'm not sure if the turbine would be most effective prior to the air injection or after. The velocity Would be greater after but what effect would the air/ water mix have. I don't even have a clue what wattage a compressor would use. An idea would be something like a well in someone's yard about 50 ft deep and 1/2 filled with the turbine partway up. Where I live this would be below the frost depth.
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Kilowatt0
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#3
In reply to #2

Re: Airlift powered microhydro turbine

09/06/2012 12:00 PM

PWSLACK wrote: "So the proposal is for a turbine to be connected to the airlift system to provide the power to make the airlift system operate and drive the turbine - is this correct?"

You wrote: "Exactly"

That is called a perpetual motion machine. That isn't allowed in this universe. Try over 2 universes to the left.

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coolEL
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Join Date: Sep 2012
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#4
In reply to #3

Re: Airlift powered microhydro turbine

09/07/2012 10:11 AM

They said the same thing and sent me to you guys:) I'll be using airlift for water return to the aquaculture tanks, would a turbine piggybacked on that system be worthwhile. Say for instance I oversize the air pump to squeeze a few kW on the side or would the air pump draw too much power to be worthwhile?
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Doorman
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Hobbies - DIY Welding - Don't Know What Made The Old Title Attractive... Popular Science - Weaponology - New Member United States - US - Statue of Liberty - 60 Year Member

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#5
In reply to #4

Re: Airlift powered microhydro turbine

09/07/2012 11:17 AM

To be certain I am catching this correctly:

You are using a water airlift to circulate water. Okay. The purpose/necessity of the airlift is to overcome the 9.81 m/s2 that is present. You are thinking of adding resistance to the lifted water, and harvesting whatever energy may be produced to compress air to run the airlift. Hmmmmnmm.

Why not use the gravity to produce the compressed air directly? Review this article about a Trompe for an explanation of how this might be done.

If you consider this scenario, you may recognize there will be no unity, the gravity tax must be paid. If you consider further the addition of a turbine and the conversion of that drag to compressed air for the airlift... whatcha think?

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PWSlack
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#6
In reply to #2

Re: Airlift powered microhydro turbine

09/10/2012 4:14 AM

Wouldn't that run contrary to the Laws_of_thermodynamics, then?

Further reading.

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czgut
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Join Date: Feb 2007
Location: Gdansk, Poland
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#7

Re: Airlift Powered Microhydro Turbine

10/19/2012 8:50 PM

efficiency of turbine You wanted to use would be low, and for sure <100%. This means, You will get back less energy from turbine, than You will be putting into airlift.

It will not work without external supply (of energy). It would be Perpetum Mobile, as others already said.
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coolEL (2); czgut (1); Doorman (1); Kilowatt0 (1); PWSlack (2)

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