FirstEnergy (NYSE:FE) announced today that it plans to retire two coal-fired Pennsylvania power plants by the end of October.

A combination of low electricity prices and high costs to meet environmental regulations has pushed the utility to action, shuttering the equivalent of 2,080 MW at the two plants, representing around 10% of FirstEnergy's total generation capacity. According to the company's press release, these two plants would have required around $280 million in environmental compliance costs, or around 30% of FirstEnergy's total estimated spending to comply with the Environmental Protection Agency's Mercury and Air Toxics Standards.

About 380 plant employees and generation-related positions are expected to be affected. The company announced the deactivation of nine plants last year.

Looking ahead, the company notes that the deactivation of these two plants will ensure that "nearly 100 percent" of FirstEnergy's electricity originates from low- or non-carbon emitting sources. Its new generation mix will be 56% coal ("clean coal" scrubbed units), 22% nuclear, 13% renewables, and 9% gas/oil.