The energy advisor to the German government has said that “the money is absolutely available” to make the global industry run on renewable power instead of fossil fuels.

And John Schellnhuber also singled out the UK for criticism of its determination to push ahead with a nuclear new build programme, saying the country was pursuing an energy “myth”.

Speaking to the Guardian newspaper in Britain, Schellnhuber – who is the founder of the Potsdam Institute for Climate Impact Research in Germany – said: “Renewables are by definition inexhaustable, so do not lead to the piling up of debts. They are also evenly spread: the wind is blowing almost everywhere, the sun is shining almost everywhere. In the end, renewables are the quintessential democratic energy source.”

He hailed Germany’s stance on renewables, saying “the German story is very encouraging” and claimed that the government’s policies had led to a “grassroots revolution on energy supply”.

Looking to the UK, he said Britain could have “a very important role if it reconsidered the role of nuclear”.

“I am a physicist and not afraid of nuclear power plants, but if you factor in all the costs including nuclear waste treatment or dismantling a nuclear plant, it is the most expensive energy source,” he said. “The myth of a low-cost, safer and easily manageable nuclear alternative to renewables is keeping the UK from becoming a member of the fitness club for the 21st century and a real partner for countries like Germany in the third industrial revolution.”