The Iowa Utilities Board has approved a 1,000 turbine wind project.
The $3.6 billion (£2.72bn) Wind XI wind farm is expected to generate up to 2GW of electricity.
It is MidAmerican Energy’s largest wind project, with 1,000 turbines to be installed by the end of 2019 at multiple sites across the state.
President and CEO Bill Fehrman said: “Wind energy helps us keep prices stable and more affordable for customers, provides jobs and economic benefits for communities and the state and contributes to a cleaner environment for everyone.”
The project is expected to generate more than $1.2 billion (£0.91bn) in landowner easement and property tax payments over the next 40 years as well as provide thousands of jobs during construction.