The cost of building two coal-fired power units at Duke Energy Corp.’s Cliffside power plant in western North Carolina has gone up to $3 billion, the company disclosed Thursday.
The Charlotte-based utility originally estimated the plants would cost $2 billion.
“The new cost figures should not come as a surprise to anyone,” said Southern Environmental Law Center attorney Gudrun Thompson in a statement. “The burden is now on Duke to justify going forward with an expensive, dirty, conventional coal plant when cleaner and more economical alternatives are available.”
Duke Energy officials did not immediately return a call seeking comment.
Duke Energy updated the $2 billion cost last month in a regulatory filing, saying that the projected price for the Cliffside project would be much higher than originally anticipated. The company did not specify how much the cost had increased, saying the details were confidential. However, Duke Energy did say it wanted to pass along the cost to customers.
The updated cost estimate was known to the utilities commission and its staff, as well as to environmental activists involved in the case who had signed confidentiality agreements.
The $3 billion figure was disclosed Thursday after environmental groups pressured the utilities commission to force Duke Energy to make the updated costs public.
“The cost of clean, renewable energy keeps coming down, but the costs of dirty coal keeps on rising,” said Michael Shore, a senior air policy analyst with the nonprofit organization Environmental Defense. “Energy efficiency and local renewable energy sources will enable us to meet demand and keep prices low.”
The four 1940s-era units operating at Cliffside sent 3.9 million tons of carbon dioxide into the atmosphere last year. By tripling the plant’s power generating capacity, its carbon dioxide production will rise despite the greater efficiency of coal burning expected from the new units, the company has said.
Emissions of sulfur dioxide, which produces haze, are expected to drop, while the new plant would have slightly increased releases of ozone-forming nitrogen oxides.
Duke has said it does not intend to implement emerging technology at the plant that can strip carbon dioxide from emissions. The technology is too expensive, according to the company, and there’s no way to store the captured gas underground at Cliffside.
Duke Energy, which has 1.6 million customers in North Carolina, contends that building new coal plants is the cheapest option for meeting future energy demand. The company is also pursuing the development of an advanced new nuclear power plant in Cherokee County, S.C.
The utilities commission was set to rule this year on Duke Energy’s application to build the coal-fired units, but the regulatory agency scheduled additional hearings for Jan. 17 to reconsider the plant because of the 50 percent cost increase.
Shares of Duke closed up 9 cents at $31.50 on the New York Stock Exchange.