In this file photo, Exelon communications director Bill Stoermer explains how banks of pressure tanks regulate nuclear reaction at the Exelon Quad Cities Generating Station in Cordova. The facility, which began producing electricity in 1973, is one of three Exelon is considering closing if the company does not receive the help it seeks from state lawmakers.

Mayors of six Illinois communities are warning of potential economic consequences if three nuclear power plants close in their areas.

Exelon Corp. has said it might have to shutter at least three of its six nuclear plants in Illinois if they can't be made profitable long-term. The Herald & Review reports the six mayors sent letters to Gov. Bruce Rauner and top state legislators saying the plants are essential to their communities.

The mayors are from Clinton, Morris, Oregon, East Moline, Braceville and Marseilles. Any debate in Springfield about the nuclear facilities also should focus on surrounding communities, they said.

"Illinois nuclear facilities provide thousands of good jobs; the kind of jobs you can support a family on," the mayors wrote in a letter dated Feb. 4.

The nuclear plants that Exelon says could close are in Clinton, Rock Island and Ogle County. Closure of the plants could cost $1.8 billion per year in lost economic activity and 7,800 jobs, according to a report from state agencies.

Exelon said the plants are having a hard time competing with other energy sources like wind that get tax breaks. Nuclear power providers have struggled with aging plants that are expensive to operate, as well as low electricity prices.

A report from several state agencies released last month said penalizing competitors that emit carbon dioxide could help Exelon's nuclear facilities stay open. The coal industry has said that plan could force plants to close. Environmentalists prefer a boost for renewable energy.

A group that's organized against Exelon called Better Energy Solutions for Tomorrow claims Exelon doesn't need help as a profitable company. But Brett Nauman, an Exelon spokesman, said looking at the entire company's financial health doesn't mean much for the nuclear plants in question.

"And if we can't find a long-term path to profitability, the company is going to consider shutting down any of these plants," Nauman said.