German electricity consumers via the EEG surcharge pay about €20bn ($23bn) per year to finance the build-up of solar, wind, biomass and other renewable energies, while the hidden costs of conventional power sources both in 2014 and 2015 reach some €40bn a year, the study says.

Included are direct subsidies and financial concessions, as well as external costs society has to come up with for environmental damage or the final storage of nuclear waste.

"Renewable