Gemany is turning one of its old coal mines into a giant 'battery station' that will store hydroelectric power and provide energy to around 400,000 homes, with hopes of launching similar facilities across the country in the coming years.
After half a century of service, the Prosper-Haniel hard coal mine in the north-west of the country is due to be shut down in 2018, when the task of getting it converted to a clean energy facility will begin.
Researchers from several German universities are working with private engineering firms and the government on the project, and have been running feasibility studies on the site since 2012. If the project is a success, more mines like this could be adapted.
The 600-metre-deep (1,969-foot) mine provides something the area doesn't have naturally – elevation. That's crucial if you want to create a pumped storage plant like this, with a reservoir on high ground usually feeding another in a valley below.
The flow of water powers turbines and generates electricity, with water pumped back up again during periods of low demand.
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