Press Release

New video from MidAmerican Energy depicts construction of tallest wind turbine

DES MOINES, Iowa – (May 23, 2016) – MidAmerican Energy Company released a video today depicting the construction of the largest land-based wind turbine ever built in the United States.

“Reaching New Heights” uses a combination of time-lapse footage, aerial photography and behind-the-scenes action shots to document the steps involved in building MidAmerican Energy’s first concrete wind turbine tower, located at the company’s Adams wind farm in Adams County, Iowa. At 379 feet from ground to hub, the concrete turbine is more than 100 feet taller than its neighboring turbines constructed with steel towers.

Mike Gehringer, vice president, renewable energy, said the 2.415-megawatt concrete turbine featured in the video is a prototype that will allow MidAmerican Energy to evaluate the amount of additional wind energy that can be generated at higher altitudes. “We want to continue to be a leader in bringing innovative energy solutions to our customers and the state of Iowa,” Gehringer said. “Through investment in new methods and new technologies, we’ll move closer to our vision of supplying customers with 100 percent renewable energy.”

MidAmerican Energy contracted with Siemens Americas Onshore Wind for the supply and construction of the concrete tower. Mike McManus, head of business development and strategy for Siemens, said the patented tower technology was conceived, designed, engineered and constructed entirely in the United States. The blades for the turbine were manufactured at Siemens’ blade factory in Fort Madison, Iowa, and the concrete formwork was sourced from EFCO Corp. in Des Moines.

Construction of the tower began in August 2015. A pair of fixed, pole-mounted cameras captured every minute of the process, from initial site work to the placement of the rotor on the nacelle. Cameras on the ground provided close-ups of workers installing the foundation and bending steel rebar to construct the tower segments, while action cameras mounted on equipment delivered scenes from inside the tower while it was being constructed. Approximately six terabytes (6,000 gigabytes) of footage shot over 31 weeks was edited down to produce the final time-lapse video, which clocks in at just under six minutes in length.

“Building a concrete tower is an entirely different process from the one we use to build steel tower turbines,” Gehringer said. “Instead of manufacturing tower sections in a factory and transporting them to the site to be fitted together, crews pour the concrete in segments and erect the tower onsite. It’s fascinating to watch it all come together in this video.”

The concrete turbine is one of 64 wind turbines at the 154-megawatt Adams wind farm. With blades extended, the turbine reaches a height of 557 feet, making it just a little taller than the Washington Monument. Watch the video detailing the construction of this record-breaking project.

About MidAmerican Energy Company
MidAmerican Energy Company provides electric service to 752,000 customers and natural gas service to 733,000 customers in Iowa, Illinois, Nebraska and South Dakota. It is headquartered in Des Moines, Iowa. Information about MidAmerican Energy is available on the company’s website, Twitter, Facebook and YouTube pages, which can be accessed via