Des Moines, Iowa, July 27, 2011 — Construction of the 443.9-MW Rolling Hills wind project in southwest Iowa is progressing on schedule toward a planned year-end completion.
A wind turbine blade was displayed at the event, providing attendees the rare opportunity to see a wind turbine blade up close. The blade, which was manufactured at Siemens' blade manufacturing plant in Fort Madison, Iowa, is about half the length of a football field and weighs 12 tons. Attendees were encouraged to sign the blade to commemorate the day's celebration.
Siemens is supplying 193 of its SWT-2.3-101 wind turbines to the Rolling Hills wind project, located in Adair, Adams and Cass counties. Each turbine is capable of producing 2.3 MW of energy.
Mortenson Construction is installing the wind turbines, as well as constructing the balance of the project infrastructure, which includes about 37 miles of access roads and about 139 miles of underground wiring.
Rolling Hills is one of three MidAmerican Energy wind projects underway in Iowa this year. Wind turbines also are being constructed in Calhoun, Marshall and Pocahontas counties.
In December 2010, at the conclusion of a competitive tender process, MidAmerican Energy and Siemens entered into a turbine supply agreement for 258 wind turbines. Mortenson Construction, based in Minneapolis, Minn., was selected through a separate competitive tender process to construct the wind projects and to install access roads, underground electrical collection systems and internal tower wiring.
When completed, the 258-wind turbine expansion project will add 593.4 MW of renewable energy to MidAmerican Energy's generation portfolio, enough capacity to power about 190,000 average homes.