Iowa has become the second-largest producer of wind power in the U.S., and some credit an aggressive and supportive role played by local government.

That support is seen in numerous ways: Wind-energy producers and equipment makers enjoy state tax breaks, and projects of 25 megawatts or smaller don't need to be certified by the utilities board. In addition, producers know ahead of time that they will be able to recover their costs from customers, which makes them more likely to invest. Iowa counties, meanwhile, appreciate the...