Exelon Corporation (NYSE:EXC) announced today that it has managed to exceed its greenhouse gas emissions reduction goal seven years ahead of schedule. It first introduced the goal in 2008.

The nuclear-centric utility revealed today that in 2013 alone, it reduced or avoided more than 18 million metric tons of greenhouse gas emissions. As part of its Exelon 2020 program, the company had previously set itself a goal of reducing annual emission by 17.5 million metric tons by 2020.

"We believe that clean, reliable and affordable energy is key to a more sustainable future. Exelon 2020 has helped us move closer to that vision," said Chris Crane, Exelon Corporation President and CEO, in a statement today. "It provided us with a clear goal, and we could not have accomplished it without the dedication and effective collaboration of our employees, customers, communities and business partners."

According to Exelon Corporation, its reduction strategy was multifaceted. The utility retired fossil-fuel-fired power plants, improved company energy efficiency, added more than 300 MW of emission-free nuclear power through uprates (increasing the maximum power level at a plant), ran customer energy efficiency programs, retired renewable energy credits, and offset its entire business travel carbon footprint.

While nuclear energy's competitiveness has recently taken a hit from relatively cheap natural gas, Cane noted nuclear's environmental advantage in his statement:

Our reliable, always-on nuclear fleet produces enough affordable, carbon-free energy to power 17 million homes annually. It is part of a U.S. fleet that provides 64 percent of our nation's carbon-free electricity, up to a quarter of which could be at risk for early retirement. Losing that generating capacity would forfeit more than half of the progress to date in meeting U.S. climate goals.