Santee Cooper has announced both generating units at the Grainger Generating Station on Highway 501 in Conway will permanently retire on December 31, 2012.
The company will also retire the two coal-fired generating units at Jefferies Generating Station in Moncks Corner.
This marks Santee Cooper's first unit retirements since the state-owned utility first generated power 70 years ago.
In October, the Santee Cooper Board of Directors voted to authorize the retirements at its two oldest and smallest stations.
That decision was in response to changing generation needs and expensive new environmental regulations that would require significant upgrades at those stations.
Grainger has been idle since the spring and most employees have already been relocated from that station.
Santee Cooper is relocating affected Jefferies employees to other positions made available through attrition, so no layoffs are anticipated.