HOW TO BUILD WIND FAST

MidAmerican Energy's Iowa Projects Put Mortenson To The Test
Mark Del Franco, 7 June 2011 (North American Windpower)

"A trio of Iowa wind farms being developed by utility MidAmerican Energy Co. promises to put Mortenson Construction to the test…because the projects - the 443.9 MW Rolling Hills, 29.9 MW Pomeroy and 119.6 MW Laurel - are being built simultaneously.

"The build-out of the wind farms began on May 16 and requires the continuous delivery and assembly of 10 Siemens 2.3 MW turbines per week until mid to late November, says Tom Budler, MidAmerican Energy's general manager of wind development, adding that 593.4 MW will bring the company's Iowa total to 1,877 MW…"

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"…Taken together, this is the largest combined project ever undertaken by Mortenson…Mortenson is nearly complete with the design and has started the construction of foundations, access roads and underground collection…[It] plans to concentrate on turbine delivery, which underscores the importance of logistics and planning.

"Some of the turbines are coming from Denmark and are arriving through the Port of Duluth, while other components will arrive from Siemens' Hutchinson, Kan., facility…[and] from the Siemens facility in Fort Madison, Iowa, by truck…The turbines for the Rolling Hills project will require more than 2,000 semi loads of turbine components, more than 8,000 truckloads of concrete and 110 miles of crane walks…"

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"MidAmerican Energy says that all three projects need to be completed by the end of the year. To ensure that the projects stay on schedule, MidAmerican Energy, Siemens and Mortenson are using a staging area near the site to pre-load about two turbines' worth of component deliveries per day…The staging calls for turbines to be shipped to the local area the day before…

"With rolling hills and terraces, the terrain near the turbine sites is challenging…[T]here are areas where the 16,000 WA cranes cannot operate, which requires them to be completely dismantled, trucked to the site, and re-assembled across the 140 square miles of the project…[Construction will also] be tricky due to the area's wet soils resulting from heavy rains…"