Republican Sens. John Barrasso, Wyo., and Shelley Moore Capito, W. Va., are asking the Federal Energy Regulatory Commission to hold technical conferences to review how the Environmental Protection Agency’s proposal to limit greenhouse gas emissions from power plants could affect grid reliability.

“The already-strong pressure for premature retirements of electric generating units coupled with the rising risks to electric reliability require you to convene representatives of entities subject to your jurisdiction and other interested parties in order to develop a record on the potential impact of the Clean Power Plan 2.0,” they said in a letter released Monday, referring to the Obama administration’s Clean Power Plan, which never took effect.

The EPA in May proposed greenhouse gas emissions limits for coal-, gas- and oil-fired power plants, with initial requirements beginning in 2030 for coal-fired generators and 2032 for gas-fired units.

The proposal would spur 22 GW of coal-fired capacity to retire, from 2023 to 2035, according to the agency. The proposal, which includes a process for allowing power plants to exceed GHG emissions limits if they are needed for grid reliability, will have little effect on grid stability, the EPA said.

The limits can be met by highly efficient operations, carbon capture and sequestration, co-firing natural gas for coal units, and with “green” hydrogen for gas generators, according to the proposal.

The EPA based those compliance pathways on “unjustifiable claims” about the future availability of carbon capture, clean hydrogen, and related infrastructure, according to Barrasso and Capito, the top Republicans on the Senate Energy and Natural Resources and the Environment and Public Works committees, respectively.

During recent Senate hearings, commissioners and officials from FERC, the North American Electric Reliability Corp. and the PJM Interconnection have highlighted growing grid reliability risks, the senators said, referring to a FERC oversight hearing and one on grid reliability.

When the Obama administration proposed the Clean Power Plan, FERC held four technical conferences to review its possible effect on grid reliability, the senators said.

“EPA clearly lacks the expertise to project accurately the impact of its rulemaking on electric reliability without deeply informed and engaged participation from FERC and those subject to its jurisdiction,” Barrasso and Capito said.

Without information from technical conferences, FERC’s consultations with EPA are likely to be ineffective, they said.

The ISO/RTO Council last month asked the EPA to extend the comment period by 60 days to give grid operators more time to assess how the proposal would affect the power system and identify mechanisms to address potential reliability concerns. The agency extended the deadline for submitting comments on the proposal by 15 days to Aug. 8.

FERC doesn’t comment on letters from members of Congress, but FERC Acting Chairman Willie Phillips will respond to it, Mary O’Driscoll, agency spokeswoman, said Wednesday.

The EPA didn’t return a request for comment.