By Emily Stephenson
WASHINGTON (Reuters) - U.S. power plants can comply with new environmental rules without disrupting the supply of electricity if providers and local authorities have time to plan for the changes, energy regulators told congressional Republicans seeking to unwind the rules.
"I believe this nation can retire a significant amount of existing generation," said Philip Moeller, a Republican member of the Federal Energy Regulatory Commission (FERC).
"The key questions are which plants are going to be retired, where are they, and what is a manageable time frame."
Republicans in Congress have vowed to block many of the Environmental Protection Agency's new rules -- which include restricting air pollution across state lines and limiting many pollutants. They say the rules would raise electricity costs and stifle job creation.
Wednesday's meeting was called by the Republican-controlled House of Representatives' Subcommittee on Energy and Power to consider a range of reports, including one by FERC staff, that estimate the EPA's rules could reduce the generation of energy by as much as 80 gigawatts.
"We will go beyond the question of how much it will cost to turn on the lights and address...whether we can depend on the lights to go on at all," said committee Chairman Ed Whitfield in prepared remarks. "We need much better answers to these reliability concerns than we have gotten thus far."
FERC commissioners said many of the studies were done before the EPA finalized its rules. State and local assessments will provide a clearer picture of the regulations' likely impact, FERC chairman Jon Wellinghoff said.
Commissioners urged flexibility in compliance for smaller plants or those in locations that would be disproportionately affected by a power plant closing.
"Smaller plants are typically older and dirtier, but there are advantages in the system to smaller plants," Moeller said. "They ramp up and down faster, might be in locations where voltage support is key."
Democratic lawmakers on the committee sought to portray their Republican counterparts as sacrificing the health of Americans to generate energy. Ed Markey, one of the authors of failed climate change legislation two years ago, called it the "tension here between air quality and air conditioning."
(Reporting by Emily Stephenson; Editing by David Gregorio)