Not since the allies leveled Germany in World War II has Europe’s biggest economy undertaken a reconstruction of its energy market on this scale.

Chancellor Angela Merkel is planning to build offshore wind farms that will cover an area six times the size of New York City and erect power lines that could stretch from London to Baghdad. The program will cost 200 billion euros ($263 billion), about 8 percent of the country’s gross domestic product in 2011, according to the DIW economic institute in Berlin.

Germany aims to replace 17 nuclear reactors supplying a fifth of its electricity with renewables such as solar and wind. Merkel to succeed must experiment with untested systems and policies and overcome technical hurdles threatening the project, said Stephan Reimelt, chief executive officer of General Electric Co. (GE)’s energy unit in the country.