Century Aluminum is proposing to continue operating its 224,000 mt/year Mt Holly smelter in South Carolina at 50% capacity even as the company on Monday began shutting down the first potline in a dispute with its longtime electricity supplier, Santee Cooper.
The two sides have been at odds for months over Century's demands to reduce Mt. Holly's power rates, nearly $50/MWh, which the Chicago-based company claims are the highest among all US aluminum smelters, making it increasingly difficult for the plant to compete in the current environment.
Century has threatened to close Mt. Holly, located in Goose Creek in Berkeley County, unless it can secure a more favorable contract with Santee Cooper than the existing deal that expires at the end of December.
Century has proposed sourcing all of the roughly 400 MW consumed by Mt. Holly from a third-party supplier and still have Santee Cooper, a state-owned utility, transmit the power to the smelter.
Century now buys 75% of Mt. Holly's power from suppliers outside of South Carolina and 25% from Santee Cooper, which transmits the power to the plant.
"At this point we are asking for 200 MW of outside power to be transmitted, which is half capacity," Century spokeswoman Samantha Dubay said in an email Monday. "We are still asking for a deal that would not impact Santee Cooper's other customers."
Dubay said Mt. Holly's first potline is in the process of being shuttered, an action expected to be completed Tuesday.
The plant's second potline would be closed December 26 if no agreement can be reached to operate the smelter at half capacity, she said.
The plant employs about 600 people. It is Santee Cooper's largest customer.
Santee Cooper spokeswoman Mollie Gore said her company still wants Century to accept its offer of extending the expiring contract and giving Century an "opt out" after six months. "It's a great offer," she said.
Although the two sides are still talking this week, Gore suggested Century's half-capacity proposal may not be acceptable to Santee Cooper.
"There would still be an impact" on the utility's other customers, she said. They include Nucor Steel's plant also in Berkeley County that Gore said is Santee Cooper's second-largest customer.
A spokeswoman for South Carolina Governor Nikki Haley indicated late last week the Republican chief executive has no plans to intervene in last-minute negotiations between Century and Santee Cooper and has done everything she can to save Mt. Holly.