Exelon Corp., the Chicago parent company of Peco Energy Co., said Wednesday it has achieved its greenhouse-gas reduction goal seven years earlier than planned.

The energy company said it has reduced or avoided 18 million metric tons of emissions - the target it set six years ago in its Exelon 2020 program - by retiring fossil fuel plants, upgrading its nuclear generation capacity, and investing in renewable power and customer energy efficiency programs.

- Andrew Maykuth