Coal- it’s the original fossil fuel. Its concentrated energy powered the Industrial Revolution, and raised humankind’s standard of living to heights that had never been possible.
But now that coal has been thoroughly supplanted by natural gas, which may soon itself be replaced by renewables, how can we restore mining communities, provide stable, high-paying jobs and an identity for former coal communities that they can be proud of? The answer may come from Germany, a country with a lot of former coal mines and ambitious renewable energy goals.
In the northwest region of the country, two professors at the University of Essen-Duisberg began to brainstorm possible uses for the old mines- the last of which will cease operations next year- and have come up with an intriguing concept: repurpose the old mines as battery storage for the wind turbines that are quickly replacing the mines in German coal country.
To turn a mine into a battery, gravity is the magic ingredient. A water reservoir would be installed at the upper level of the mine shaft, storing energy when the winds are high, and releasing it to a lower reservoir when the wind dies down, using the gravitational energy of water rushing down to turn turbines and generate electricity. The biggest drawback? It’s expensive- André Niemann, one of the professors who conceived the project, estimates that it would cost between 10,000 and 25,000 euros per meter of tunnel just to build the reservoir, and around 500 million euros for the whole thing. Right now, neither the government nor the energy companies in the Ruhr Valley are willing to make that kind of investment. So the project may not become reality anytime soon. But that hasn’t stopped governments from all over the world- including the US- from sending scientists and researchers to check out their work.
Even so, local German governments are trying to figure out how to use the country’s renewable energy boom to transition dirty energy workers into clean energy workers. It’s still a work in progress, and some estimates say Germany may not achieve its goals on the current timeline. But the hard work they are doing to solve the problem of how to transition coal country away from coal may hold vital lessons for our country as well.