wind farm repowering
Image credit: Siemens Gamesa

Siemens Gamesa has been selected by MidAmerican Energy Company for the largest repowering order in US history – the renewal of the Rolling Hills wind power project for a total of 429.3 MW.

The company will repower the project with 163 SG 2.7-129 and 18 previously sold SWT-2.3-108 wind turbines.

Rolling Hills is located in Adair, Adams and Cass counties in Iowa and currently features 193 SWT-2.3-101 turbines. The repowering project includes replacement of the blades, hubs and nacelles for all units, and top tower sections for the SG 2.7-129 units. Commissioning of the project is expected for late 2021.

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“We are excited to provide upgraded equipment and technology to the Rolling Hills project in Iowa, a national leader in the wind energy industry. This new project is a testament to MidAmerican Energy’s confidence in us as well as Iowa, where we have supplied them with more than 2.6 GW,” stated José Antonio Miranda, CEO of Onshore Americas at Siemens Gamesa Renewable Energy. “The blades will be produced right there in Iowa and the nacelles and hubs will come from neighboring Kansas, making this a truly local project.”

Siemens Gamesa has installed more than 10,000 wind turbines in the U.S. totalling approximately 20 GW of installed capacity. In Iowa, Siemens Gamesa has installed nearly 1,400 wind turbines for a total of almost 3.5 GW. The company has a strong footprint consisting of service, offices and two manufacturing facilities located in Fort Madison, Iowa, and Hutchinson, Kansas.