Solar power in Iowa on rooftops can provide 20% of all electricity used in Iowa. A 2012 estimate suggests that a 5 kW array will pay for itself in utility savings in 18 years and generate a profit of thereafter. On June 7, 2012, Sky Factory in Fairfield became the first company in the state to generate all of their electricity from solar power, with the installation of a 54 kW 3500 sq. ft. solar array. Prior to that one of the largest arrays was the 15.75 kW array on the Marshalltown Public Library.
Net metering is available continuously to all consumers generating up to 500 kW, one of the best policies in the country but is given a B because of not being available to large, megawatt users. A feed-in tariff is available for customers of the Farmers Electrical Cooperative for up to 25% of their electricity. It pays 20 cents/kWh for electricity generated, none of which can be directly used – a separate meter is required, in a parallel connection, making it a power purchase agreement, instead of a feed-in tariff. The state of Iowa has proposed a feed-in tariff, in Senate bill SF 225. A separate rate applies for systems less than 20 kW and systems from 20 kW to less than 20 MW.
In December 2011, Des Moines based MidAmerican Energy Holdings, a Berkshire Hathaway company, purchased the Topaz Solar Farm, which when completed, at 550 MW, could be one of the largest in the world.