Energy Northwest's nuclear power plant near Richland is generating an average of an additional 22 megawatts of power as a result of improvements made during last year's lengthy outage.
"Cost of power varies with the market, but regardless of market cost, 22 megawatts of increased public power output will have a substantial positive impact -- potentially $6 million per year -- on regional cost-of-power," said Brent Ridge, Energy Northwest vice president and chief financial and risk officer, in a statement.
For comparison, 22 megawatts represents 80 percent of the electric generation potential from Energy Northwest's Packwood Lake Hydroelectric Project near Mount Rainier.
The Columbia Generating Station now averages about 1,170 megawatts of electrical generation, which is nearly 10 percent of the power generated in Washington.
The improved efficiency comes from replacement of the plant's main generator rotor and condenser plus maintenance conducted during the refueling outage that's scheduled every two years.
The outage did not go as planned, with it stretching from an anticipated 80 days to about 175 days as work to replace the condenser was more time consuming than expected.
The contractor on the project, Babcock and Wilcox, sued Energy Northwest, saying that it failed to reveal information about the project when it bid. Energy Northwest, which also complained about B&W's performance, has agreed to settle the lawsuit for about $18 million.
B&W had a $33 million contract for the work, which was part of a $113 million proposed budget for the project.
The condenser, which was more than 25 years old, turned steam generated by boiling water in the nuclear reactor back into water for re-use.
Despite the difficulties of the condenser replacement, Energy Northwest is seeing the benefits now.
Not only is power production improved, but the new condenser improves reliability of the plant, which was the primary driver of the project, said Brad Sawatzke, the plant's chief nuclear officer.
The region depends on the Columbia Generating Station to provide a consistent baseload of power, particularly in the seasons when hydropower and wind generation are not at their peaks.
The new condenser also prepares the plant for an extended operating license. The plant was granted its first operating license in 1983 and Energy Northwest expects to hear this week that the Nuclear Regulatory Commission will approve a 20-year license extension that would allow the plant to operate through 2043.
The increased power production is due not just to the new condenser but also other maintenance done during last year's outage.
Maintenance was conducted on more than 350 steam-related valves and work was done to improve efficiency on two of the plant's six cooling towers, in addition to a wide range of other maintenance and improvement projects.
"A lot of work was done to ensure the plant continues to operate reliably, and averaging 22 extra megawatts of generation is a huge bonus," said Mark Reddemann, Energy Northwest chief executive, in a statement. "It bolsters Columbia's already impressive low cost-of-power record, which ultimately benefits Northwest ratepayers."