Gaildorf pioneers electricity storage

A pilot project in a small town close to Stuttgart in Germany shows how the Water Battery will work in the future. The foundations of the four most powerful wind turbine generators will be used as upper reservoir for this purpose. They are connected via an underground penstock to a pumped-storage hydro power station in the valley that can provide up to 16 megawatts in power. The electric storage capacity of the power plant is designed for a total of 70 megawatt hours.

Facts and Figures

Wind turbine capacity: 4 x 3,4 MW
Rotor diameter: 137 m
Annual electricity generation from wind power: 42 GWh
Turbine hub height above ground: up to 178 m HH
Pumped-storage plant capacity: 16 MW
Electrical storage capacity: 70 MWh
Water fall height: 200 m
Water volume: 160.000 m³
Active reservoir: up to 40 m
Passive reservoir: 8–13 m


Meters HH


MWh storage capacity


m3 water volume


MW turbine capacity

Support from the BMUB:7.15 million euros of funding for the pilot project

The German Federal Ministry for the Environment, Nature Conservation, Construction and Reactor Safety (BMUB) is supporting the project in Gaildorf with funds from its environmental innovation programme amounting to 7.15 million euros. This is a clear mark of recognition for this innovative technology, which is being demonstrated for the first time in a large-scale technical application.


The background: During times when the wind blows strongly, surplus renewable energy is often generated that cannot be fed into the public electricity grid or stored. Instead, the energy production is throttled back and the wind turbines are shut down. In the pilot project in Gaildorf, on the other hand, the electricity is temporarily stored in the upper basin.

Learn more about how the Water Battery works.