A US appeal court rejected on procedural grounds a legal challenge to the Environmental Protection Agency’s (EPA) proposed emissions rule for existing power plants.

The three-judge panel of the U.S. Court of Appeals for the District of Columbia Circuit said various lawsuits objecting to the Clean Power Plan (CPP) were premature because the regulation has not yet been finalised, and legal challenges would have to wait until it is formally issued.

The ruling had been expected after two of the three Republican-appointed judges expressed doubts during an April hearing over the lawsuits filed by more than a dozen US states and Murray Energy Corp.

”The first legal challenge to the CPP failed today, and others the polluters will trot out should fail as well … The Supreme Court has three times already upheld EPA’s duty to tackle carbon pollution and climate change,” David Doniger, director of the Natural Resources Defense Council’s Climate and Clean Air Program.

The so-called Existing Source Performance Standards (ESPS) would require US utilities to cut CO2 emissions 30% under 2005 levels but the EPA is only due to finalise the measure in August.

Separately, the White House’s Office of Management and Budget may be reconsidering the government plans to impose tough CO2 limits on new plants under the CPP over concerns the existing proposal could be overturned in court, ICIS reported last week, citing unnamed sources.

Under the EPA’s initial blueprints new power plants would face limits of 499kg of CO2/MWh, but critics reportedly doubt that any new coal-fired installations could meet this criteria without CCS.

According to ICIS, there are also worries that the 2005 Energy Policy Act prohibits the EPA from setting performance standards under the Clean Air Act for commercial power plants based on the use of technology being tested at projects funded by the Department of Energy under its clean coal power initiative (CCPI).

If the EPA is prevented from setting a standard that is not based on CCS, the entire CPP could be delayed and its future jeopardised by next year’s presidential election.

As a result, sources told ICIS that the EPA may ditch the CCS requirement and raise the CO2/MWh limits for new plants to a more achievable level.

By Ben Garside – ben@carbon-pulse.com