A wind energy equipment manufacturer says it will lay off 615 workers in Iowa, Kansas and Florida in part because Congress has not renewed a tax credit for wind energy.

Siemens Energy Inc. says it told workers the news Tuesday at plants in Fort Madison, Iowa; Hutchinson, Kan., and Orlando, Fla.

The biggest cuts will come in Fort Madison, where 407 workers at a wind turbine blade factory will be out of work. About 220 workers there will be retained.

The company blamed difficult market conditions due to lack of congressional action on a wind energy tax credit as well as increased use of natural gas-fired power plants and an overall sluggish economy.

In a statement, Siemens says the industry is seeing a significant drop in new wind turbine orders.

Wind turbine blades from the Siemens Energy blade factory in Fort Madison. (PRNewsFoto/Siemens Energy)