Siemens Gamesa has been selected by MidAmerican Energy Company to repower the Rolling Hills wind power project, sized at a total of 429.3 MW, the largest repowering order to date in North America. 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.