While it’s good news for the air we breathe, the accelerating pace at which coal-fired power plants are being retired has a flip side. When coal-fired plants go offline, they take a major volume of generating capacity with them, and utilities must ensure they have the resources and the grid reliability to cover the loss.

One utility that recognizes this challenge is FirstEnergy Corp. of Ohio. Customers of the utility in Ohio and neighboring mid-Atlantic states are in for a change. The Akron-based company has announced an ambitious plan to upgrade transmission infrastructure in a five-state area that also includes Pennsylvania, West Virginia, New Jersey and Maryland. The company says the upgrades are needed as it retires coal-fired plants in the region because of strict Environmental Protection Agency standards for mercury and other air toxins. For the company and many other utilities, it is simply more cost-effective to deactivate some aging facilities than it would be to bring them up to environmental standards.

FirstEnergy plans to spend up to $900 million over the next five years on various related projects. Projects include new and rebuilt high-voltage power lines, new substations, and specialized voltage-regulating equipment.

One highlighted project is a new 340-kilovolt (kV) transmission line that will run more than 100 miles from the company’s Bruce Mansfield Plant in Beaver County, Pa., to a new substation that will be built in the Cleveland suburb of Glenwillow. The new substation will connect with two existing 345-kV transmission lines that run through the Glenwillow community.

FirstEnergy reports that all of its projects have been approved by PJM Interconnection, the regional transmission organization that oversees reliability for a 13-state area. The Glenwillow-Bruce Mansfield Project also will be reviewed by the Ohio Power Siting Board and the Pennsylvania Public Utilities Commission. The utility has an in-service date for the project of June 2015.