As we’ve discussed many times, Germany is one of the industrialized countries leading the transition to renewable energy, and an important part of this transition will be finding efficient ways to store renewable energy. As one innovative solution, a German engineering professor, André Niemann, wants to turn an old, underground coal mine into a giant battery for renewable energy.
As part of Germany’s big push toward renewable energy, the federal subsidies the carbon-intensive coal industry has relied heavily on are due to expire in 2018. When that happens, Germany’s 3 existing hard-coal mines will no longer be viable. It’s one of these mines Niemann wants to put to use as a giant battery.
The proposal involves turning the deep tunnels of the Bergwerk Prosper Haniel mine, which is about an hour from the city of Cologne, into pumped storage. Renewable energy that is not needed at any given time would be used to pump water into an above ground reservoir. To retrieve that energy later when its needed, the water would be drained downhill (just using gravity) into the mine and through turbines, making the whole system into a massive hydraulic battery. Some renewable energy would be used to pump water back to the surface again.
To be clear, this is not a new idea, it’s proven, and a few of these types of systems are already operating around the world, including in Germany and the United States. However, this would be the first time preexisting coal mine infrastructure would be put to use.
Watch the embedded video form more details on the proposed project, Germany’s remaining coal use, and the country’s push for renewable energy.