RWE Innogy, Siemens and German energy company Stadtwerke München are planning to build an offshore wind farm off the North Wales coast.
Work on the 576MW Gwynt y Môr wind farm will begin towards the end of 2011 and is expected to be completed by 2014.
RWE Innogy will hold a 60% stake in the joint venture, Stadtwerke München 30% and Siemens 10%.
The firms will provide investment proportionate to their stakes, totalling over €2bn ($2.3bn) including investment on grid connection to the coast.
Siemens Energy will be responsible for the supply, erection and maintenance of the 160 3.6MW wind turbines on the farm and for connecting it to the mainland, under a €1.2bn ($1.4bn) contract.
The wind farm is planned to start generating electricity as early as 2013 and once complete in 2014 is expected to generate about 1,950GWh of electricity annually.