The Supreme Court ruled that EPA acted “unreasonably” when it failed to consider costs before deciding to regulate mercury and other toxic emissions from power plants under the Clean Air Act.

A top EPA official gave the most detailed hints yet about how the agency will revise the Clean Power Plan when the final rule is released this summer.

This week's FERC and federal briefs include news on the Environmental Protection Agency, the Nuclear Regulatory Commission and the NTSB.

Arkansas PSC Chairman Ted Thomas is no fan of the EPA’s Clean Power Plan, but he’s perhaps even more critical of congressional Republicans.

Since the EPA proposed its Clean Power Plan, the idea that the final rule should include a reliability safety valve has become an article of faith among utility, state and RTO officials.

A federal appeals court Friday threw out the 2013 EPA rule exempting diesel generators providing demand response from air emissions limits.

The U.S. electric industry will face reliability concerns in four years if the interim goals of the Environmental Protection Agency’s Clean Power Plan aren’t relaxed, the North American Electric Reliability Corp. said last week.

Grand River Dam Authority (GRDA); operators of an Oklahoma coal-fired generator seeking a temporary reprieve from EPA's MATS rule won an assist from FERC.

SPP’s next 10-year transmission plan will consider three future scenarios to assess the potential impact of EPA’s Clean Power Plan.

SPP could comply with the EPA’s Clean Power Plan through a $45/ton carbon adder and 7.8 GW of additional generation, most of it wind, the RTO said.