The wind farm, which is located in north-east Oregon near Arlington, has a 20-year power purchase agreement with Southern California Edison.



In December 2009, Caithness handed GE Energy a $1.4 billion contract to install its 2.5MW turbine at the project. All 338 turbines for Shepherds Flat include a rarely seen 10-year O&M coverage contract. California's Alta Wind Energy Centre is technically bigger at over 1GW, although it is a combination of smaller projects.



Last year, Google and subsidiaries of the ITOCHU and Sumitomo corporations announced they were investing $500 million in the $2 billion wind farm.



ITOCHU’s subsidiary is Tyr Energy, which owns a mixture of gas, geothermal and natural gas projects. Sumitomo invested through its US arm, which owns the 120MW Stanton wind project in Texas.



In October 2010, The US Department of Energy (DOE) has offered a partial guarantee on a $1.3 billion loan to finance the project.



"The opening of Caithness Shepherds Flat, one of the world's largest wind farms, demonstrates that we can deploy renewable energy at scale with the help of private capital," said Rick Needham, Director of Energy & Sustainability at Google.



Derrel Grant, Vice President of Development at Caithness Energy said: "Caithness Shepherds Flat is a prime example of smart energy – energy that simultaneously bolsters the economy, creates American jobs, and enhances our environment for future generations.



"By utilizing domestic renewable energy, Caithness Shepherds Flat will help make our country energy independent and our economy prosperous."



