An executive of NextEra Energy said Wednesday the company would add up to 2,000 megawatts of wind-generated electricity in Iowa to the 800 megawatts it already generates.

But NextEra Vice President Michael O'Sullivan said his company would need the same rate of return that MidAmerican Energy of Des Moines has requested from the Iowa Utilities Board for its proposed 1,001-megawatt project.

NextEra, a subsidiary of Florida Power & Light Co., has objected to the MidAmerican proposal, saying the 12.2 percent allowable rate of return it requests would give it an advantage in raising capital. That would dry up other investment in Iowa's already large and growing wind industry. MidAmerican's request for the 12.2 percent rate of return will be heard by the Iowa Utilities Board on Aug. 10.

"We just want a level playing field," O'Sullivan told The Des Moines Register editorial board on Wednesday. "If MidAmerican is allowed a 12.2 percent rate of return on its project, it will have a chilling effect on other outside wind investment in Iowa."

O'Sullivan said NextEra - which has wind farms in Cerro Gordo, Hancock, Osceola, Story and Winnebago counties - has asked MidAmerican for a joint venture to sell wind energy from any future new projects but has been rebuffed.

But MidAmerican's vice president for regulatory affairs, Dean Crist, said the utility would be open to discussions with NextEra.

"We've said in our testimony that this proceeding does not preclude us from doing business with NextEra if their offer to sell assets to us is consistent with rate-making principles," Crist said Monday.

Iowa already ranks second among U.S. states, with 3,000 megawatts of wind power, trailing only Texas.

More generation is expected as discussions continue over a transmission superhighway that would carry wind-generated electricity from the "wind belt" from North Dakota and South Dakota and Minnesota through Iowa east to Chicago and to the Eastern seaboard.

Such transmission lines would create a potentially lucrative wholesale electricity business for wind farms in Iowa.

MidAmerican has moved to take advantage of that possibility and new tax incentives - plus a surplus of wind turbines - with a proposal to the Iowa Utilities Board for a 1,001-megawatt wind farm on a yet-undisclosed location in Iowa.

NextEra is a "merchant generator," meaning that it creates and sells electricity in Iowa at the wholesale level but does not provide residential or commercial service, as does MidAmerican.

As a nonregulated merchant generator, NextEra cannot qualify for the kind of allowable rate of return on any capital project as could MidAmerican.