HARRISBURG — The centerpiece of Gov. Tom Wolf’s plan to fight climate change took another step Tuesday toward the final regulatory threshold to impose a price on carbon dioxide emissions from fossil fuel-fired power plants in Pennsylvania.

The Environmental Quality Board, composed primarily of Wolf appointees, approved the plan 15-4 to send it on to the Independent Regulatory Review Commission, which could take it up this fall.

Wolf, a Democrat, wants to the plan to take effect next year as part of a multi-state consortium, the Regional Greenhouse Gas Initiative, which sets a price and declining limits on carbon dioxide emissions from power plants.

It has broad opposition from the fossil-fuel sector and Republican lawmakers, raising the possibility of a court challenge.

If Wolf is successful, Pennsylvania would become the first major fossil fuel state to adopt a carbon pricing policy. The heavily populated and fossil fuel-rich Pennsylvania has long been one of the nation’s biggest polluters and power producers.

The initiative is a key part of Wolf’s goal of reducing Pennsylvania’s greenhouse gas emissions by 80% by 2050. Carbon dioxide is the most pervasive greenhouse gas, but not the most potent, according to researchers.

Imposing a price on carbon emissions is projected to reduce air pollution, improve health, boost the economy and jobs, and raise tens of millions of dollars annually for energy programs, Wolf administration officials said.

Electric bills would rise in the short-term, but by 2030 would be lower than they are now, Wolf’s administration projects.

Pennsylvania would be, by far, the biggest emissions state in the consortium of northeastern and mid-Atlantic states.

Under the cap-and-trade program, Pennsylvania’s dozens of power plants fueled by coal, oil and natural gas would be forced to buy credits annually, one for each ton of carbon dioxide emitted.