Essentially the same energy-balance idea as Dinorwic in N Wales , where water is pumped up to a reservoir during low-tarrif times and released through turbines during peak demand.

Phil, Málaga, España

..is this the worlds first perpetual motion machine.
Michael, Idle, uk

No. This is hydro-pumped storage. A viable energy storage system is what wind power needs to be a success. Wind is unpredicatable. This system allows energy to be stored until it is needed for use. This is a good idea.

J Holmes, Glasgow,

what ever happened to the Morecambe Barrage Scheme back in the sixties

noel matthews, grand rapids, usa

"The electricity generated by the water pouring in is matched or exceeded by that needed to pump it out."

Wow, perpetual motion at last. Those cunning Dutch.

jon livesey, Sunnyvale, CA/USA

James, agree it's technically a 'waste' of energy but this is exactly the type of scheme we need if we wish to take renewables >10%, otherwise you need oil/gas backup plants to compensate for when the wind drops. We already have differences in price at different times of the day due to supply/demand

Ryan G, London,

Excuse me but is this the worlds first perpetual motion machine.

Michael, Idle, uk

This is essentially a storage device for wind energy.

Plenty of wind - surplus energy pumps water out.

Not enough wind - let water in and use hydroelectric power.

"Rynner", Falmouth, UK

Better still why not use the windmills (mechanical energy) to make the pumps (mechanical) work and use the pumps plus tidal action to raise/lower the water volume inside the "island" and use the positive/negative water flow for electricity generation. Energy conversion always wastes some energy.

Robin , Winchester, UK

Why they don't use solar power to pump the water out?

Greg, Derwood MD, USA

Essentially an overall waste of energy. This is essentially a huge battery, storing electricity as potential energy of the sea water to rush inside.
I assume that this is just a lossy storage device to provide power when the wind stops blowing and people do not misunderstand it as an energy source.

James Pipe, Southampton, UK

It's energy neutral / negtive as it pumps the water out. Why not tidal barrages / wave that extrace energy from the sea?

Richard, london, England

Very sensible and repeatable almost anywhere in the world-

Scott Benowitz, Rye, New York, U.S.A.

Very sensible and repeatable in UK waters.

Dan, London, UK