Alliant Energy Corp, which now buys 336 MW of wind generation in Wisconsin and Iowa, intends to buy or build another 230 MW in the next few years. Serving customers in Wisconsin, Minnesota, Illinois and Iowa, the utility says it will add 1600 MW of diverse generation to its energy portfolio by 2010 to meet load growth. But Alliant's Janice Mathis says 130 MW of wind generation in Iowa and 100 MW in Wisconsin is likely to be built earlier in that timeframe. Iowa currently has 481.8 MW of installed wind capacity and Wisconsin has 53 MW. Alliant has not decided whether to develop the projects itself or seek bids from developers. Rather than own wind farms, the Madison-based utility has historically bought wind generation because of decisions by Wisconsin regulators that discouraged owning generation. Now, however, the Public Utility Commission is "approving some self-owned generation" and is "granting a nice return on equity" for those power plants, she says. The $650 million, 1600 MW portfolio excludes the use of a base load coal plant, previously scheduled for construction. At the same time it announced its generation expansion, Alliant said it would reduce emissions at its existing power plants, participate in the emissions trading market and retire some old power plants prior to 2010.