The 645-page plan, expected to be finalized next year, is a centerpiece of Obama's efforts to deal with climate change and seeks to give the United States more leverage to prod other countries to act when negotiations on a new international treaty resume next year. Under the plan, carbon emissions are to be reduced 30 percent from 2005 levels, in what would amount to one of the most significant U.S. actions on global warming.
Obama, in a conference call hosted by the American Lung Association, said the plan would both shrink electricity prices and protect the health of vulnerable Americans. He scolded critics who he predicted would contend anew that the limits would crush jobs and damage the economy.
"What we've seen every time is that these claims are debunked when you actually give workers and businesses the tools and the incentives they need to innovate," Obama said.
The proposal sets off a complex regulatory process, steeped in politics, in which the 50 states will each determine how to meet customized targets set by the Environmental Protection Agency, then submit those plans for approval.
"This is not just about disappearing polar bears or melting ice caps," said EPA Administrator Gina McCarthy. "This is about protecting our health and our homes. This is about protecting local economies and jobs."
Some states will be allowed to emit more pollutants and others less, leading to an overall, nationwide reduction of 30 percent.
Many states that rely heavily on coal will be spared from cutting a full 30 percent. West Virginia, for example, must reduce the pollution it puts out per amount of power by 19 percent compared to the rate in 2012. Ohio'starget is 28 percent less, while Kentucky and Wyoming will have to find ways to make 18 percent and 19 percent cuts in their electricity generation's efficiency.
On the other extreme, New York has a 44 percent target, EPA figures show. But New York already has joined with other Northeast states to curb carbon dioxide from power plants, reducing the baseline figure from which cuts must be made. States like New York can get credit for actions they've already taken, lest they be punished for taking early action.
Initially, Obama wanted each state to submit its plan by June 2016. But the draft proposal shows states could have until 2017 — and 2018, if they join with other states.
That means even if the rules survive legal and other challenges, the dust won't likely settle on this transformation until well into the next administration, raising the possibility that political dynamics in either Congress or the White House could alter the rule's course.
Although Obama doesn't need a vote in Congress to approve his plans, lawmakers in both the House and Senate have already vowed to try to block them — including Democratic Rep. Nick Rahall, who faces a difficult re-election this year in coal-dependent West Virginia. Scuttling the rules could be easier if Republicans take the Senate in November and then the White House in 2016.
Another potential flash point: The plan relies heavily on governors agreeing to develop plans to meet the federal standard. If Republican governors refuse to go along, as was the case with Obama's expansion of Medicaid, the EPA can create its own plan for a state. But the specifics of how EPA could force a state to comply with that plan remain murky.
S. William Becker, who heads the National Association of Clean Air Agencies, said it was good that the rule will give states more time to develop strategies and will grant credit for previous steps to cut emissions.
"Still, the regulatory and resource challenges that lie ahead are daunting," Becker said.
Power plants are the largest U.S. source of greenhouse gases, accounting for about a third of the annual emissions. EPA data show power plants have already reduced carbon dioxide emissions by nearly 13 percent since 2005, meaning they are about halfway to meeting the administration's goal.
The EPA projected that carrying out the plan will cost up to $8.8 billion annually in 2030, but the actual costs will depend heavily on how states choose to reach their targets. The administration argued that any costs to comply are far outweighed by savings in health expenses that the U.S. will realize thanks to reductions in other pollutants such as soot and smog that will accompany a shift away from dirtier fuels.
Environmental groups hailed the proposal, praising both the climate effects and the public health benefits they said would follow. Former Vice President Al Gore, a prominent environmental advocate, called it "the most important step taken to combat the climate crisis in our country's history."
But energy advocates sounded alarms, warning of economic drag. Senate Minority Leader Mitch McConnell, R-Ky., called the proposal "a dagger in the heart of the American middle class."
"If these rules are allowed to go into effect, the administration for all intents and purposes is creating America's next energy crisis," said Mike Duncan of the American Coalition for Clean Coal Electricity, which represents the coal industry.
Options for states to meet the targets include making power plants more efficient, reducing the frequency at which coal-fired power plants supply power to the grid, and investing in more renewable, low-carbon sources of energy. States could also enhance programs aimed at reducing demand by making households and businesses more energy-efficient. Each of those categories will have a separate target.
Coal once supplied about half the nation's electricity, but has dropped to 40 percent amid a boom in natural gas and renewable sources such as wind and solar. Although the new emissions cuts will further diminish coal's role, the EPA predicted that it would remain a leading source of electricity in the U.S., providing more than 30 percent of the projected supply.
Obama has already tackled the emissions from the nation's cars and trucks, announcing rules to reduce carbon dioxide emissions by doubling fuel economy. That standard will reduce carbon dioxide by more than 2 billion tons over the lives of vehicles made in model years 2012-25.
Reach Dina Cappiello at http://twitter.com/dinacappiello and Josh Lederman at http://twitter.com/joshledermanAP
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