The utility initially planned to convert the plants in Walterboro to natural gas fuel before retiring them in 2017.
A third was retired at the end of last year.
“After reevaluating system needs and analyzing the economics of the situation, the company decided to proceed with retiring the plant by the end of this year,” it said.
SCE&G first outlined its plan last year, responding to the US Environmental Protection Agency’s Mercury Air Toxic Standards, or MATS.
It identified six coal-fired units, including the three at Canadys station, to be taken offline or switched from coal to natural gas via an integrated resource plan with the South Carolina Public Service Commission.
The six make up 730 megawatts of the company’s generating capacity and, ranging in age from 45 to 57 years, are SCE&G's oldest and smallest coal-fired units.
Generation and transmission president and chief operating officer Steve Byrne said retiring the older coal units, including those at Canadys, would help it to meet increasingly stringent environmental regulations while also balancing its portfolio.
“By the end of 2018, we anticipate that roughly one-third of our electric generation will be fueled by nuclear power, one-third by natural gas and one-third by scrubbed coal-fired plants," he said.
The Canadys station employs 69 workers and the utility will assist employees in locating other positions within the company.