German scientists to test new approach to store wind-power

[DetlefK]

http://www.suedkurier.de/region/bodenseekreis-oberschwaben/ueberlingen/Strom-aus-der-Betonkugel-auf-dem-Seegrund;art372495,8475988
(article in german, because it seems nobody outside Germany has reported on this)

What's the big problem with environmentally friendly energy-sources like wind and solar?

Their output fluctuates, based on weather, making regulations of the electric grid extremely difficult.

If only there were a way to save the energy during times of over-production and then release it at a later time...



The "Fraunhofer-Institut für Windenergie und Energiesystemtechnik" (Fraunhofer institute of wind-energy and energy-system-technology) has proposed a cheap way to solve this problem for off-shore windparks: You attach an off-shore wind-turbine to a hollow beton sphere resting on the bottom of the sea.
- Initially, the sphere is filled with seawater.
- During times of over-production (e.g. a thunderstorm), a water-turbine pumps water out of the sphere with an electro-motor.
- When you need electricity, you let water flow back into the sphere, the water-turbine now driving the electro-motor, which means it acts as a generator for electricity.

?version=1453906149

A test-trial with a 3-m-sphere in a depth of 100 m is planned for this year. The final version is planned to be a 30-m-sphere in 700 m depth.

[eppur_se_muova]

1. An "inside-out dam" -- interesting. nt

[kristopher]

2. I sketched out a back of the envelope design for this about 10 years ago.

Pretty obvious concept; I'm glad we're at the point where it's worth pressing forward.