WASHINGTON, Nov 25 (Reuters) - Democratic Commissioner Cheryl LaFleur has been named acting chairwoman of the U.S. Federal Energy Regulatory Commission, the agency said on Monday.
The move was expected after the previous chairman, Jon Wellinghoff, left FERC on Sunday.
FERC regulates elements of the U.S. natural gas, electricity, oil and hydropower industries, including the reliability of the electricity grid and the licensing of liquefied natural gas export terminals.
In recent years it has instigated high-profile investigations against major banks, including JP Morgan Chase & Co and Barclays PLC for energy market manipulation and false reporting.
The agency imposed more than $304 million in fines against energy companies in fiscal 2013, its highest ever.
Wellinghoff's term ended on June 30. He had agreed to stay on until a replacement was confirmed.
The White House's original selection as the new FERC chief, Colorado regulator Ron Binz, withdrew his nomination in October after failing to win support from a key congressional panel. President Barack Obama has not announced a new nominee.
Wellinghoff was recently criticized by some lawmakers for staying on, even after announcing that he will join Stoel Rives LLP, a law firm specializing in energy and environmental litigation, after leaving the agency.
LaFleur, originally from Massachusetts, has a law degree from Harvard.
She joined the commission in 2010 after a long career in the electric and natural gas industry, including a stint as acting chief executive officer at the utility company National Grid USA, a subsidiary of National Grid Plc.
The elevation of LaFleur leaves the five-member commission one member short and - with two Democrats and two Republicans - potentially deadlocked on certain decisions.