Alliant’s new Iowa wind farm producing energy

Alliant Energy has completed the startup of its first wind farm in Iowa.

The last of 121 newly installed Vestas V-82 wind turbines at the Whispering Willow Wind Farm-East in Franklin County was commissioned in the last few days. Each of the turbines can produce 1.65 megawatts of electricity, or enough to power about 400 homes at full capacity.

The utility is investing more than $400 million in the wind farm, and expects to ask for a rate hike to pay for it next year. The Iowa Utilities Board has approved ratemaking principles that ensure the utility will receive a 11.7 percent return on equity over a 25-year depreciation period.

The investment “helps us balance the need to provide affordable energy to our customers while at the same time making sure we're utilizing new technologies to reduce our impact on the environment,” said Tom Aller, president of Alliant's Interstate Power & Light utility.

The wind farm will offset about 2 million tons of carbon dioxide emissions per year, along with lesser emissions of nitrogen oxides, mercury and sulfur oxides. Alliant officials said that, compared with coal-fired generation of electricity, it is equal to taking 309,000 standard-sized automobiles off the road each year.

Alliant's first company-owned wind farm was in Wisconsin. But the 200-megawatt Iowa wind farm has more than three times the generating output of Cedar Ridge Wind Farm in Wisconsin.

Alliant expects to add another 200 megawatts of wind power in 2011 in southern Minnesota, bringing wind energy up to 14 percent of Alliant's total energy mix.

Alliant's previous wind ventures in Iowa were developed and owned by other parties, with Alliant agreeing to buy the energy output under long-term contracts.