Germany's top four utilities E.ON, RWE, EnBW, Vattenfall have set aside €38bn ($41.4bn) to pay for the decommissioning of the country's remaining nuclear power stations and the final storage of highly radioactive waste.

But preliminary estimates assume the costs for the nuclear decommissioning and waste storage to cost at least €50-70bn, the DIW says.

Also, the provisions aren't protected from insolvencies, and the utilities could also try to escape their responsibility by restructuring their businesses, claim the authors of the DIW study – energy experts Claudia Kemfert, Christian von Hirschhausen and Cornelia Ziehm.

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