CLEVELAND, Ohio -- Dirtier air and higher electric bills are probable, argues a pro-nuclear group, if FirstEnergy's power plant subsidiary closes its three nuclear power plants and Exelon closes one in Pennsylvania.

Nuclear Matters, a national nuclear advocacy organization, released a report this week written by economic consulting company, the Brattle Group, that argues gas and old coal power plants -- rather than wind and solar -- would generate more electricity to make up for the loss of the four nuclear plants.

The report comes as the U.S. Department of Energy continues to accept comments on a formal request by FirstEnergy Solutions that the DOE invoke a rarely used section of the Federal Power Act to save old nuclear and coal plants in the name of national security. The law grants the extraordinary power to the DOE to deal with crises such as war or natural disasters.

The release of the Brattle report also comes just days after Jack Gerard, president and CEO of the American Petroleum Institute, wrote directly to President Trump suggesting that granting the request from FirstEnergy Solutions would "be at odds with your stated goals of energy dominance, economic growth and improving America's infrastructure."

FES has asked the DOE to order independent grid managers and federal power regulators to keep its plants (and by extension other old nuclear and coal plants) operating by creating a wholesale market rate structure that would allow them to compete with cheaper power generated by new gas turbine plants and wind farms.

The FES emergency appeal to the DOE followed an earlier rejection by the Federal Energy Regulatory Commission of a similar request by the coal industry.

The Brattle analysis, which is based in part on earlier separate studies it did in Ohio and Pennsylvania, calculates that allowing the four nuclear plants to close would increase carbon dioxide emissions in the region by 21 million tons per year along with increases in other pollutants such sulfur dioxide and oxides of nitrogen.

The four nuclear plants generated an average of 39 million megawatt hours per year between 2013 and 2017, the report notes, about 50 percent more power than wind and solar generated in 2017.

"These four nuclear plants produce considerably more zero-emission generation, and thus avoid considerably more fossil emissions, than all solar and wind generation in the entire PJM region combined," the report concludes.

Arguing that building additional wind and solar would take years, the report projects that gas plants would make up about 72 percent of the lost nuclear generation and the remaining 28 percent would come from coal-fired plants.

The nuclear plant shutdowns would also affect the economy, the report argues, reducing the Ohio gross domestic product by as much as $510 million a year and costing as many as 4,200 jobs in Ohio alone. But the analysis does not include any costs in keeping the plants open, the authors warn in a footnote.

Other reaction was muted, in part because the DOE has opened a webpage calling for public comment on the FES request for an emergency order saving old power plants.

PJM Interconnection, which manages the grid in Ohio, 12 other states and the District of Columbia, noted that its competitive wholesale markets have created a reliable and least-cost grid.

"While we appreciate the importance to a state of other social or environmental public policy objectives, we believe a market-oriented alternative offers a superior approach to further those objectives. For example, while there is no national carbon policy and most states have no carbon policy, PJM has indicated that market-based mechanisms can be implemented that would allow states to achieve carbon reduction goals in an economically efficient manner," PJM commented in an email in response for a comment.

David Lochbaum, a nuclear safety engineer with the Union of Concerned Scientists, and not an opponent of nuclear energy, suggested "Common Sense Matters" might be a better option.

He said the decommissioning of other nuclear power plants already under way has not led to economic disasters.

"The unemployment in the other states is not rampant, despite the permanently shut down reactors. The price of electricity in the other states is not exorbitant, despite the permanently shut down reactors," he said.

"So, why does Nuclear Matters believe the folks in Ohio and Pennsylvania cannot figure out what folks in other states have figured out?" he asked.