Small scale water turbine generator

[itsmoked]

YouSlube Turbine vid

This is surprising to me as I've always seen the turbine at the very last millimeter of the penstock. Is this a normal install? Is nothing (major) being lost in translation here or should the turbine actually be at the end?

I'm trying to equate the 500 watts being generated with 'could you pump that much water from the after bay back up to the reservoir with that same 500W'? Seems like you'd need more than a horsepower to move that much making me think there's a huge efficiency hit going on. ??

Keith Cress
kcress -

http://www.flaminsystems.com

 

[1503-44]

Cabin looks a bit remote. I wouldn't think he's feeding a grid. I doubt there is a power co anywhere near that place.

 

[itsmoked]

-39 those grid ties do nothing without a POCO grid. That was why he had another set of wires to stop grid tie if it ever went negative and actually sent power back to the power company as the POCO meter would bill him for positive net power. Q.E.D he is hooked to the grid.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[bacon4life]

The DC side looked a bit too small to carry 524 watts @ 24V.

energy.gov has a formula for residential size hydro: Watts = Head(ft) * GPM / 10
So 500 watts at 15ft gives 333 GPM. His system looks pretty goofy( using the ground wire on UF as a current carrying conductor, venturi effect suction, etc) but it seems like he's actually doing pretty well.

Was the 333 GPM based on something real, or just back-calculated from the energy.gov formula? Hydraulics is not my thing, but dropping the pipe dimensions into a random flow calculator at

http://www.calctool.org/CALC/eng/civil/hazen-williams_g,

it says that under gravity flow a 6 in pipe with 15 ft head would have a discharge of 3200 GPM. A head of just 0.25 ft would induce more than 333 GPM in the pipe.

 

[FacEngrPE]

The 3200 gpm would be a free flowing siphon. Once a turbine is inserted, it will restrict the flow to a smaller value, If we make an assumptions that the poor arrangement reduces efficiency by 50% from the energy.gov calculator, we could make a reasoned guess the flow rate is closer to 550 gpm, than 3200 gpm.

In this application efficiency probably does not matter much, just that the owner is satisfied with the results.

 

[LittleInch]

But as he says he sometimes runs out of water.

If he was more efficient the he wouldn't and get more power.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[bacon4life]

Sometime satisfied owners quickly become unsatisfied when they find out a minor change could vastly improve an installation. I am still unclear as to whether the turbine would perform slightly better, dramatically better, or no differently if placed further down the hill.

 

[waross]

This may be the turbine runner.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[LittleInch]

So a reverse axial pump.

Looks like a Kaplan turbine.

You still don't want to create too low a pressure downstream the turbine apparently

https://en.wikipedia.org/wiki/Kaplan_turbine

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[LittleInch]

Bacon,it looks to me like the unrestricterd flow in the down leg is resulting in a pressure at the end of the turbine which is too low and results in inefficiency.

What the owner should do is introduce a variable restriction and then measure power versus opening of the valve once he gets the flow going. At some point there will either be a drop off or flattening of the power curve vs opening ams that's max power.

I suspect it's about half of the current flow. ...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[waross]

I suspect it's about half of the current flow. ...

Is there a pun in here somewhere?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[LittleInch]

Ha.

No. I meant water flow.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.