Any comments on this large energy storage device? 7

[MartinLe]

Look at this:

http://www.heindl-energy.com/

Essentially they plan to cut a large plug from bedrock, raise it by pumping water underneath to store energy:

The thing looks insane. They address a few design issues on their site. I'm unsure about the feasiblity, what do you think?

 

[rb1957]

"doubt there's a good site to build the plug." ... someone else's back yard ?

so "at best" this'd make available 70% of the energy it took in ? so this is more about allowing the main line power stations run at constant, or at worse a slowly varying, load and so allow these to be more efficient. The point of this is to harness the potential energy of the plug. what sort of water pressure are we talking about ?

another day in paradise, or is paradise one day closer ?

 

[BUGGAR]

"doubt there's a good site to build the plug." ... someone else's back yard ?
Not a bad idea. When a house connects to the water utility, they have to provide their own energy plug in their back yard. They could put a platform on it and give the kids a ride while storing and retrieving energy. The resources are all in place: pressure, quantity of media (except maybe during drought), distribution.

 

[zeusfaber]

if I recall correctly some of the early hydraulic accumulators did just use a mass on top of the column of water

You're right. There's still one like that works the machinery at Bristol Docks. There also used to be (may still be) one to lift the bascules at Tower Bridge in London.

A.

 

[KENAT]

Thanks zeus, I didn't think I was imagining it but a quick google didn't explicitly confirm it.

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[HCBFlash]

Interesting, but the challenges presented are substantial, and the energy required to construct it will go unrecovered. Water storage is useful, but this mechanism would only be useful in certain situations, probably not in most parts of North America, Europe, China, much of South America, or northern Asia, because of the plenty of natural elevation changes, and within good transmission distances from utilization areas.

.


Me wrong? I'm just fine-tuning my sarcasm!

 

[zeusfaber]

I was down at the Underfall Yard in Bristol just after Christmas and grabbed a photo of the old accumulator.

Round the back, they have a cafe with a working model. Various relatives enjoyed being pumped up and down to play the part of the deadweight.

A

 

[LittleInch]

Insane? No
Realistic? Equally no.
There's no way you can excavate a solid plug like that. You would never be able to cut the horizontal section unless you mined it out and then propped it up while you sealed the base of the"cylinder"

The cost of the concrete shell,the seal, the hundreds of rollers compared to the storage capacity must be uneconomic.

The pressure even of an un feasible 100m high plug is only 26 bar.

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

 

[prc]

I believe a much more simpler and probably cheaper solution may be convert existing hydropower stations in to pumped storage plants. Build a small check dam at tail rise and pump water at day time and reverse flow to generate power at night.[link ]Link[/url]

 

[MikeHalloran]

Raising an obelisk with pulleys and wire rope and hydraulic pump/motors might be sort of practical, but archaeologists have yet to figure out how the Egyptians made the horizontal cut to free the obelisk from the rock.

Giant o-rings or rolling bellows working against cut rock faces do not sound viable.



Mike Halloran
Pembroke Pines, FL, USA

 

[3DDave]

How to make it isn't all that impossible - just money.

If you want a narrow kerf, sink a shaft alongside the plug.
Dig horizontally to the edge of the future plug.
Dig a circular tunnel under the desired cut line.
Drill two small passages from the surface to the tunnel and feed cutting cable down one side, around a pulley in the tunnel, and then back up to the cutting rig through the other hole. The original holes can be filled with epoxy/cement and are cut to finished width with an overcut.
Move the cutting rig along the top and move a turning pulley along the bottom to make the cut.
When the plug side is finished, move the cable drive or turning pulleys to the bottom of the side shaft and place pulleys at either side of the opening, with the cable looped around the plug base.
As the cable cuts, backfill to support the plug and prevent cable pinching. Access to backfill the cut will be available immediately behind the cable as it advances.

Cable cutting does wonders on limestone and ships; no reason to believe that it can't work here, just a matter of cost/time.