WASHINGTON — The Environmental Protection Agency moved forward with a proposed rule to require coal-fired power plants to install a technology aimed at reducing greenhouse gases that the Government Accountability Office found won’t be commercially viable for several years.

The EPA first proposed new caps on carbon dioxide emissions from fossil-fuel fired electricity generating units in April 2012 and received more than 2.5 million public comments on the rules. In the proposed rule filed with the Federal Register on Wednesday, the EPA said it is withdrawing the 2012 proposal and moving forward with new substitute rules.

“This action proposes a separate standard of performance for fossil fuel-fired electric utility steam generating units and integrated gasification combined cycle units that burn coal, petroleum coke and other fossil fuels that is based on partial implementation of carbon capture and storage as the best system of emission reduction,” the rule states. “This action also proposes standards for natural gas-fired stationary combustion turbines based on modern, efficient natural gas combined cycle technology as the best system of emission reduction.”

The new rules would put a limit on emissions of carbon dioxide to 1,100 pounds per megawatt-hour of electricity from coal-fired plants. For new natural gas plants, the threshold is 1,000 pounds per megawatt-hour. Smaller natural gas plants get a 1,100-pound limit.

To meet those standards, plants will have to install carbon capture and sequestration technology, which stores the carbon dioxide in geologic formations. A 2010 GAO study found that the technology might be ready in 10 or 15 years, dependent on overcoming economic, legal and technical hurdles — but those barriers remain unconquered today.

“Stakeholders told GAO that while components of CCS have been used commercially in other industries, their application remains at a small scale in coal power plants, with only one fully integrated CCS project operating at a coal plant,” that report said. “…In particular, with respect to CCS, stakeholders highlighted the large costs to install and operate current CCS technologies, the fact that large scale demonstration of CCS is needed in coal plants, and the lack of a national carbon policy to reduce CO2 emissions or a legal framework to govern liability for the permanent storage of large amounts of CO2.”

“…According to reports and stakeholders, the successful deployment of CCS technologies is critical to meeting the ambitious emissions reductions that are currently being considered in the United States while retaining coal as a fuel source. Most stakeholders told GAO that CCS would increase electricity costs, and some reports estimate that current CCS technologies would increase electricity costs by about 30 to 80 percent at plants using these technologies.”

Because of the effect opponents say the new rules will have on jobs, they wryly noted the date that the administration chose to proceed with the regulations.

“It’s absolutely unbelievable that on the 50th anniversary of the war on poverty, the EPA has just announced another regulation that will increase poverty in coal country,” said Sen. John Barrasso (R-Wyo.).

“Less than one day after President Obama pledged to help unemployed Americans, his administration is rolling out red tape that will destroy more jobs and increase energy costs,” Barrasso said. ”In addition to contradicting current law, this new regulation will put more Americans out of work and make it even harder for people to provide for their families. It’s now more important than ever for Congress to pass the National Energy Tax Repeal Act and protect American jobs across coal country.”

That bill, which would “prohibit any regulations promulgated pursuant to a presidential memorandum relating to power sector carbon pollution standards from taking effect,” is stuck in committee with 14 Republican co-sponsors representing coal country.

The leading Republican on the Senate Environment and Public Works Committee noted that the EPA leaned on three Energy Department funded studies to justify the requirement that CCS technology be “adequately demonstrated” — even though the EPA is forbidden by law from relying on Clean Coal Power Initiative studies to meet that standard.

“In typical EPA fashion, they’re putting the cart before the horse to advance their environmental policy agenda,” said Sen. David Vitter (R-La.). “They’re moving forward with a controversial rule to regulate carbon based on technology that isn’t commercially available.”

“Not only is this wrongheaded, it’s beyond the scope of their legal authority.”

The Sierra Club lauded the setbacks for the coal industry in 2013, noting that 30 percent of coal plants currently operating in the U.S. have announced plans to “retire.” Over the past year, an average of three coal plants per month announced they would shut down.

“Now, more than ever, it’s clear that it is twilight for coal in the United States,” said Bruce Nilles, senior director of the Sierra Club’s Beyond Coal campaign. “2013 was the year that clean energy became cheaper than coal. Add in that no one is building new coal plants, and the only remaining question is how quickly can we replace the remaining coal plants.”

The U.S. boasts nearly 30 percent of the globe’s coal reserves and generates about 40 percent of the electricity used in the country.

“Unfortunately, the proposed rule will also stymie future research into clean coal technologies and/or carbon capture utilization and storage. Is this an unintended consequence, or an intended one?” said Betsy Monseu, CEO of the American Coal Council.

The Environmental Defense Fund said today that “while some folks may be dismissing climate change because of the current blisteringly cold weather in parts of the U.S., we are still very clearly seeing the long-term trend of warming that experts at leading scientific and government agencies (like NASA and many, many others) agree is occurring.”

“There are opposition forces working to derail EPA’s efforts to address carbon pollution. We need all of the support we can muster to ensure EPA goes forward with its commonsense standards that will help ensure the healthier, clean energy future we know we must achieve for the sake of our children and grandchildren.”

Comments on the revised rules close on March 10.