By Valerie Volcovici
WASHINGTON, Feb 27 (Reuters) - Swapping power generated from the dirtiest coal plants with that from under-used natural gas plants would help U.S. states meet new regulations for greenhouse gas emissions, according to a plan released by an environmental group on Thursday.
The proposal by the Boston-based Clean Air Task Force (CATF) is the latest to be presented as the U.S. Environmental Protection Agency prepares new emissions standards for existing power plants, due for release on June 1.
President Barack Obama last June directed the EPA to propose the national standards to lower carbon emissions that states could meet through their own tailored plans.
The CATF found that a relatively small amount of switching from coal to natural gas could help achieve a 27 percent cut in carbon dioxide emissions from the power sector by 2020, compared with 2005 levels. At the same time it would prevent electricity rates from rising more than 2 percent.
The group said the easiest and most affordable way for states to achieve these standards would be for them to be assigned a carbon emission "budget" by the EPA - a cap on the amount of carbon they can pump into the atmosphere.
They would then be able to participate in emissions credit trading schemes that encourage operators to switch from dispatching power from inefficient old coal plants to underused natural gas plants.
The group hopes its plan can provide states that have not yet developed a strategy to reduce their carbon emissions in a way that meets future EPA power plant standards, said Conrad Schnieder, advocacy director of CATF.
"We see this plan as providing a feasible, legally defensible pathway to reduce emissions from existing plants," Schneider said.
While many expect the EPA to give the states a lot of leeway in how to meet the national standards, Schneider said the agency should also offer them some readymade options that they could follow.
The program suggested by CATF would be an alternative to a carbon trading program now operating in California, as well as the Regional Greenhouse Gas Initiative in the northeast U.S. Both have achieved significant cuts to emissions.
CATF is one of several groups that have offered frameworks for the EPA's eagerly-awaited power plant proposal.
The Natural Resources Defense Council offered the first comprehensive blueprint for the EPA in December 2012 that would cut carbon pollution through a state-driven program to encourage energy efficiency.
A group of utilities and lawyers, the National Climate Coalition, proposed a framework to that would allow power plants to achieve emissions reductions using tools such as such as averaging and trading emissions. (Reporting by Valerie Volcovici; editing by Andrew Hay)