Thanet Offshore Wind Farm off the coast of Kent, England, is a precursor to the North Sea project.

Swedish energy company Vattenfall announced today that it's partnering with Germany's largest utility to build a massive offshore wind farm in the North Sea at a cost of about 1 billion euros ($1.4 billion) .

The DanTysk wind farm will consist of giant wind turbines supplied by Siemens and spaced out over a 70-square-kilometer area about 70 kilometers (42 miles) west of the German island of Sylt. Construction is scheduled to begin in 2012 and to wrap up by the start of 2014.

Once complete, the 288-megawatt wind farm is expected to produce about 1,320 gigawatt-hours of electricity annually. That's roughly enough electricity to meet the energy needs of 500,000 homes, assuming an average use of 2,500 kilowatt-hours per home, according to Vattenfall.

The wind farm will be used to power Munich's subway and tram system, as well as supply renewable electricity to thousands of German households.

Vattenfall, which will construct and maintain the offshore wind farm, owns a 51 percent interest in the venture. Stadtwerke Munchen, Germany's largest municipal utility, has invested in a 49 percent share.

"The city of Munich needs strong and reliable partners like Vattenfall to accomplish its overall mission, that Munich by 2025 will be supplied purely with renewable energy from its own generation plants," Kurt M&252'hlh&228'user, Stadtwerke Munchen CEO, said in a statement.

Vattenhall is no stranger to supersized renewable energy projects.

In September, the Swedish company completed the first phase of the Thanet Offshore Wind Farm, a project off the southeast coast of England, which has been dubbed the largest offshore wind farm in the world to date.