The 200-megawatt wind-energy project is expected to be operational by the end of 2010 and will generate enough electricity to power the equivalent of 50,000 to 60,000 homes annually, the company said.
Power utility PacifiCorp will purchase the electricity and any renewable-energy credits generated by the project, as part of a 20-year purchase agreement, the company said.
Duke Energy said it plans to start construction on the project in late 2009 or early 2010. It said it will use at least 66 General Electric turbines at the site. The wind farm will be Duke's fourth in Wyoming.