The nuclear power plant near Richland reconnected to the grid Friday morning after shutting down for 41 days for a planned refueling and maintenance outage.
Columbia Generating Station should be back to full power within a few days.
Energy Northwest’s nuclear power plant, the only commercial nuclear power plant in the Northwest, schedules a refueling outage every other spring to replace about half of its fuel assemblies and also to do maintenance work best performed when the plant is not operating.
The outages are timed to start in May when spring snow melt and runoff maximizes power output from the region’s hydroelectric dams.
That minimizes the impact of not having the nuclear plant sending electricity to the grid. Nuclear and hydro are the region’s only full-time clean energy sources, says Energy Northwest.
The plant was back on-line after its 24th refueling outage just in time to meet higher electricity demand as summer temperatures heat up, Energy Northwest said.
The plant hired about 1,200 temporary workers from the Tri-Cities and across the country to help with the work. They were in addition to about 1,000 permanent employees.
133-ton rotor installed
“The refueling and maintenance we do is fairly complex work that requires a highly skilled team,” said Grover Hettel, Energy Northwest chief nuclear officer. “It’s a rigorous, five-week, non-stop 24/7 operation.”
Workers replaced 260 of the nuclear plant’s 764 nuclear fuel assemblies in the reactor core during the outage.
Fuel stays in the reactor core about six years. When it’s removed, it is placed in a used fuel pool and then eventually moved to dry cask storage at the Columbia Generating Station. The storage site is on leased land at the Hanford nuclear reservation about 10 miles north of Richland.
The largest maintenance project during the outage was installing a 34-foot, 133-ton refurbished low-pressure turbine rotor. It’s part of the life-cycle plan to satisfy the plant’s license extension to 2043.
The fire detection system also was upgraded, and robotics were used to perform a generator inspection.
Outage work boosts production
In all, workers completed about 1,300 work orders with more than 7,500 tasks.
The outage was budgeted to cost $127 million for refueling, maintenance and capital purchases.
The work should bring substantial value to the region, Hettel said.
From 2010 to 2017, equipment replacements, refurbishments and upgrades increased the nuclear power plant’s gross generation capacity from 1,150 megawatts to 1,207 megawatts.
During 2018, the plant sent more than 9.7 million megawatt-hours of electricity to the grid, a record for its 34-year operating history.
Columbia Generating Station continues to produce electricity equivalent to what is needed to power Seattle and part of its metro area.
All of the electricity produced at the nuclear power plant is sold at cost to the Bonneville Power Administration.