As the dust settles on President Obama's climate action plan released Tuesday, industry and advocacy groups here are trying to sort out this:

How much will it hurt coal, the region's traditional but fading power source? And how much will it boost renewables and nuclear?

In both states, a cascade of regulatory blows has forced coal-fired power plants to upgrade, close, or switch to natural gas.

In both, two nuclear generators are on the drawing boards.

Wind energy has grown in Pennsylvania. New Jersey is a national leader in solar power, and plans for offshore wind farms are progressing.

"Given energy growth, we will need all of them," said Gene Barr, president of the Pennsylvania Chamber of Business and Industry.

The state's historic link to mining made it a national leader in coal-fired energy plants, along with their unhealthy emissions. Its aging fleet of roughly three dozen coal-fired power plants produces 43 percent of the power generated in the state.

"It is safe to say the impact [of Obama's plan] would be significant," said State Rep. Ron Miller, a York County Republican who chairs the House Environmental Resources and Energy Committee. He highlighted the economic benefit of cheap electricity from coal and the 63,000 people employed in the mining industry.

But in the most recent state rankings from the U.S. Environmental Protection Agency, Pennsylvania ranks third in the nation in carbon dioxide emissions from fossil fuel combustion, based on 2010 emissions. That year, nearly half the state's emissions came from generating electricity.

The state's emissions have since declined because natural gas has begun to displace coal.

Nine of its roughly three dozen coal-fired power plants have announced deactivations and retirements. Some plants have announced a switch to natural gas.

Jake Smeltz, president of the Electric Power Generation Association, a Pennsylvania industry group, said that if the new rules force more closures, the ripple effect would be dramatic.

"We're not going to reopen coal mines. We're not going to reconstitute rail lines that deliver coal. We're not going to fire up boilers that have sat unused," he said. "When you say goodbye, you really do say goodbye."

In New Jersey, coal-fired power plants aren't as big a part of the power mix. The bulk of the state's carbon dioxide emissions come from transportation, the EPA report shows.

Its two major coal-fired power plants have already spent hundreds of millions of dollars to upgrade. But the new plan would likely make them do more.

The coal industry has criticized Obama's "war on coal," saying it will cripple the economy.

Companies that rely heavily on electricity worry their costs will go up and they'll lose out globally.

"Our members, when we ask them, 'What keeps you up at night,' aside from cost of health care, they bring up the cost of energy and competitiveness," said Michael Egenton, vice president of government relations at the New Jersey Chamber of Commerce.

But, said Philadelphia's Gretchen Alfonso, a field manager for the advocacy group, Moms Clean Air Force, rising asthma rates and other pollution-related health problems make it clear "this is not a war on coal, this is protection of our children's health."

Both states have strong nuclear power profiles.

New Jersey's Oyster Creek nuclear plant is headed for closure within the decade. But there are three units at the Salem and Hope Creek plants in South Jersey, and PSEG has initiated the lengthy process of building a fourth unit nearby.

Pennsylvania has five nuclear plants, and PPL has proposed building another unit near its Susquehanna plant, northeast of Harrisburg.

Environmental groups in New Jersey are hoping the president's action plan pushes Gov. Christie to address climate change more vigorously.

The state has made significant progress and can be "a national model," said Doug O'Malley, interim director of Environment New Jersey. "Unfortunately, Gov. Christie has rolled back that progress," in part by pulling out of the Regional Greehouse Gas Initiative, a market-based effort to cut emissions.

Pennsylvania legislators see an opportunity to push for more renewable energy, such as solar and wind.

State Rep. Greg Vitali, Democratic chair of the House Environmental Resources and Energy Committee, and three dozen other legislators want to see the state increase the amount of alternative energy that electric utilities are required to provide, which would boost investment in projects.

In 2009, the Pennsylvania legislature ordered the Department of Environmental Protection to prepare a climate action plan. Its 52 recommendations would have cut the state's greenhouse gas emissions by a third and created 65,000 jobs, said then-DEP Secretary John Hanger, now a gubernatorial candidate.

The plan has gathered dust ever since, Hanger said, and he'd like to see it implemented.

Meanwhile, companies that focus on new technologies for energy efficiency - another goal of the Obama plan - are hoping for an infusion of reseach and development funds. Many anticipate a growth spurt.

At one Philadelphia company, that has already happened.

Within the last week, knowing Obama's announcement was imminent, Independence LED's CEO Charlie Szoradi added four people - an increase of 25 percent - to his local sales staff. The company installs energy-efficient lighting in commercial buildings.

He sees Obama's plan, bolstered by recently instituted PECO rebates and a city plan requiring energy benchmarking for office buildings, as crucial.

"This is a boost for us," he said. "A massive boost."

Contact Sandy Bauers at 215-854-5147, sbauers@phillynews.com, or follow

on Twitter @sbauers. Read her blog, GreenSpace, at www.inquirer.com/greenspace