WASHINGTON (Reuters) - Iowa’s Republican senator on Wednesday raised concerns that U.S. Energy Secretary Rick Perry has commissioned a “hastily developed” study of the reliability of the electric grid that appears “geared to undermine” the wind energy industry.

FILE PHOTO - U.S. Sen. Chuck Grassley (R-IA) speaks to reporters after the weekly Republican caucus policy luncheon at the U.S. Capitol in Washington, U.S. April 4, 2017. REUTERS/Eric Thayer

In a letter sent to Perry, Senator Chuck Grassley asked a series of questions about the 60-day study he commissioned. Grassley also said the results were pre-determined and would show that intermittent energy sources like wind make the grid unstable.

Last month, Perry ordered the grid study and said Obama-era policies offering incentives for the deployment of renewable energy had come at the expense of energy sources like coal and nuclear.

“I’m concerned that a hastily developed study, which appears to pre-determine that variable, renewable resources such as wind have undermined grid reliability, will not be viewed as credible, relevant or worthy of valuable taxpayer resources,” wrote Grassley, whose state is home to a booming wind energy industry.

He pointed to a previous study conducted a few years ago by the Energy Department’s National Renewable Energy Laboratory, which took two years to complete, not two months.

Grassley said Iowa gets 36 percent of its electricity from wind and that its largest utility, MidAmerican Energy Co, is on track to generate 90 percent of its electricity from wind in a few years. Grassley said MidAmerican has the ninth lowest electricity rates in the country.

In the letter, Grassley also asked Perry which grid-reliability organizations and experts were involved in the study, how much it would cost taxpayers and whether the report would be open for public comment.

Perry served as governor of Texas, a leading oil-producing state, from 2000 when he succeeded President George W. Bush until 2015. Under his tenure, Texas became the country’s leading wind energy producer.

But Perry has also been a strong advocate of the fossil fuel industry. He told Department of Energy staff that he wanted them to examine whether environmental regulations and tax credit programs that bolster wind and solar energy are forcing coal and nuclear plants to shut down prematurely.

Grassley has been a leading proponent in Congress for the continuation of a wind energy production tax credit. The current credit is due to phase out over the next few years before ending in 2020.