"In light of the situation, we will carry out a safety check of all nuclear plants," Chancellor Angela Merkel. Germany's total nuclear capacity is greater than 20GW. The seven oldest reactors have been taken offline for three months while an assessment of the safety and ethical aspects of nuclear operation is carried out. Some reactors may stay permanently offline. An eighth reactor, offline since 2007, brings the total idle nuclear capacity to 8.3GW.
In comparison, Germany's wind fleet now exceeds 27GW, albeit generating 36.5TWh last year compared with nuclear's 140.5TWh.
With less nuclear generation on the networks, there could be fewer occasions when wind energy would need to be curtailed because the wind is blowing strongly and demand is low. It may prove trickier, however, to keep the high-voltage transmission network stable because most of the reactors now offline are located in southern Germany, increasing the need for north-south flow of power on a network configuration originally designed for flow in the opposite direction.
"We can't predict what will happen," says Cornelia Junge, spokeswoman for high-voltage transmission network operator Tennet. "We are currently examining the effects of shutting down the reactors - we'd expect some geographical shifts in flows and possibly more electricity imports."
Any increase in imports - which would ironically come from nuclear plants in France and the Czech Republic - will depend on whether the electricity can be generated more cheaply abroad or from Germany's remaining overcapacity in fossil-fuel power stations.
The nuclear closures could result in higher power prices, but this may benefit wind and renewables by narrowing the difference between generation costs of wind and other renewables and the wholesale price of power. This, in turn, reduces the size of the renewable energy levy paid by power consumers.
Meanwhile, the nuclear catastrophe in Japan has awakened more people to the hazards of nuclear power, resulting in a boom in customers switching to green electricity tariffs and indicating more sympathy for wind and other renewables.
Thousands of people have taken to the streets in anti-nuclear protests. A previously arranged 65,000-strong demonstration at the Neckarwestheim reactor in southern Germany on 12 March took on unexpected significance as news of Japan's nuclear problems following the previous day's earthquake spread across the world.
Since then, protests have stepped up considerably, with anti-nuclear vigils in around 700 German towns and cities attended by around 160,000 people and major demonstrations in Cologne, Berlin, Hamburg and Munich.
Parts of the federal government now say renewables expansion should be speeded up. Vital for this is a swift government signal that the Renewable Energy Sources Act amendment, due to take effect in January 2012, will not alter support conditions for wind energy, says the federal wind energy association.
Without clear information by mid-2011, uncertainty on project financing will lead to delays for planners that will slow wind expansion next year, it warns. More political support for wind energy in Germany's southern states would also speed expansion there and provide replacement electricity for potential permanent nuclear closures where it is needed most, says the organisation.