German wind farm to use hydroelectric batteries

Posted on 13 Nov 2016 by Michael Cruickshank

A world-first project in Germany is combining wind power with hydroelectric batteries for energy storage.

Announced earlier this month, the new plant will combine four large wind turbines with a holding dam and hydroelectric turbines in order to produce a constant flow of electricity.

Built by GE Renewable Energy in collaboration with Max Boegl Wind AG, the plant aims to solve one of the most persistent problems facing both wind and solar power.

Currently, these forms of renewable energy are unable to take the role of ‘baseload’ power as they cannot produce power at night (in the case of solar) or when the wind is not blowing (in the case of wind power).

One solution is storing energy in the form of large Lithium-ion batteries, however these are both inefficient and expensive.

Instead, the new wind/water project being built by GE will use the gravitational potential energy of water as a kind of battery, raising it uphill with wind-powered pumps when the wind is blowing, and then feeding it downhill to a hydroelectric turbine when it isn’t.

In order to get this to work, GE is building four of the largest wind turbines in the world, capable of producing 13.6 megawatts of electricity and standing at a total height of 584 feet (178m) when complete.

Each will sit in a reservoir holding up to 9 million gallons (34 million liters) of water, which can then be fed to a hydroelectric plant 600 feet (182.9m) below on the valley floor capable of producing 16 megawatts of power.

Another advantage inherent in this design is that energy can be stored when the price of power is low, and then sold when the price is high, making it more profitable than traditional renewable power installations.

“Germans in this area are known as tinkerers and inventors,” said Cliff Harris, general manager for onshore wind in EMEA at GE Renewable Energy. “So the mentality of this technology really fits with the population.”

The current project, located in the Swabian-Franconian forest, will be operational by the end 2018, however Max Boegl Wind plans this as just the first of many such installations. They envisage being able to install two such plants annually in the near future.

While more expensive than a regular installation, GE Renewable Energy believes that the technology will prove itself in the long term. “The plant will run for several decades, and we expect the benefits will be felt over that time,” Harris said.