Germany has shut down its oldest nuclear reactor as part of the country's plan to phase out nuclear power by 2020.
Germany plans to increase use of alternative energy sources
The 36-year-old 340-megawatt plant in the southwestern town of Obrigheim was turned off at 0758 (0558 GMT), said energy firm EnBW.
It is the second of Germany's 19 reactors to be closed down.
To replace the energy demands, the government is proposing investment in other sources such as wind power.
Germany's nuclear programme and its efforts to reduce its reliance on fossil fuels have made it a leader in efforts to fulfil the Kyoto protocol.
But there have been concerns that the country could be creating an energy crisis for itself.
Chancellor Gerhard Schroeder's Social Democrats and their environmentalist Green partners in the ruling coalition reached agreement with Germany's main energy providers in 2001 to phase out nuclear power.
Under the current legislation, each of Germany's 19 reactors will be phased out on its 32nd birthday - at which point it is closed.
The first to close was the Stade nuclear reactor, near Hamburg, which is now awaiting decommissioning.
Germany already produces 40% of all the world's wind power and the hope is that by 2010, wind will meet 12.5% of German energy needs.
The country has 16,000 wind turbines, mostly concentrated in the north of the country, near the border with Denmark - including the biggest in the world, owned by the Repower company.
Reuters says the Biblis A nuclear reactor, which has been used since 1975, will be the next one to close in February 2007.