Pennsylvania has become a leader in the fight to diminish dangerous atmospheric warming. It is now the largest power-producing state within the 12-state Regional Greenhouse Gas Initiative, a multistate consortium that sets a price and declining limits on planet-warming carbon dioxide emissions from power plants.

Last month, a legislative agency published Gov. Tom Wolf's carbon-pricing rule in the official record of state agency actions, authorizing the commonwealth to join RGGI. It will make Pennsylvania the first major fossil fuel state to adopt a carbon-pricing policy.

It comes after a long regulatory vetting process and fights with a hostile legislature controlled by Republicans who are historically protective — and rightly so — of Pennsylvania's coal and natural gas industries.

But it might be a short-lived victory. One lawsuit already is challenging Wolf’s regulation and more are expected. And the term-limited Democratic governor has just months left in office and may be replaced by a successor who opposes RGGI.

Heavily populated and fossil fuel-rich Pennsylvania has long been one of the nation’s biggest polluters and power producers, and the jury is out on whether the carbon-pricing program on power plants will significantly reduce greenhouse gas emissions.

Wolf’s administration estimates that joining RGGI will reduce Pennsylvania's carbon dioxide emissions by 97 million tons to 225 million tons through 2030. That compares to its estimate that the state emitted 269 million tons of carbon dioxide equivalents in 2018.

Under the cap-and-trade program, owners of fossil-fuel power plants with a capacity of 25 megawatts or more must buy a credit for every ton of carbon dioxide they emit.

As a result, roughly four dozen power plants fueled by coal, oil and natural gas in Pennsylvania must buy hundreds of millions of dollars in credits annually that the state could use to spend on clean-energy or energy-efficiency programs.

That gives fossil fuel plants an incentive to lower their emissions, and makes nonemitting plants — such as nuclear plants, wind turbines and solar installations — more cost competitive in power markets.

Energy has been a constant theme this year's gubernatorial campaign for Republican candidates vying for the nomination to succeed Wolf.

“We have a governor that wants to put us in a Regional Greenhouse Gas Initiative that will literally eliminate gas in Pennsylvania,” Republican candidate Lou Barletta told a forum in Erie recently. “So the first thing I’m going to do for energy is withdraw Pennsylvania from RGGI.”

Barletta's claim that it will eliminate gas is baseless: even some operators of higher-efficiency gas plants support the move.

RGGI also is opposed by coal- and natural gas-related interests that fear higher input costs, industrial and business groups that fear higher electricity bills and labor unions that fear its workers will lose jobs maintaining power plants, building gas pipelines and mining coal.

Critics and even independent analysts say it will drive at least some business — and carbon dioxide emissions — to gas- and coal-fired power plants in neighboring states where input costs are lower and there are no emissions caps.

Pennsylvania may not stay in the consortium even if Wolf's successor is Democrat Josh Shapiro, the party's presumed nominee who is endorsed by Wolf.

Last October, Shapiro broke with Wolf, with his campaign telling The Associated Press that it's not clear that the cap-and-trade program meets the test to “address climate change, protect and create energy jobs and ensure Pennsylvania has reliable, affordable and clean power for the long term.”

Gene Barr, the president and CEO of the Pennsylvania Chamber of Business and Industry, which opposes the regulation, said the big questions are how the state's Supreme Court will rule — it has a Democratic majority — and what Shapiro will do, if elected.

“It is hard to guess,” Barr said. “But regardless of what happens this year, there’s both legal and implementation challenges to RGGI.”

— JGG