Alliant Energy’s Riverside power plant near Beloit needs $25 million in repairs
One of Alliant Energy Corp.’s key power plants serving the Madison area has been out of service since September and is not expected to restart until July, the Madison utility company confirmed Wednesday.
But an Alliant spokesman said he does not expect a shortage of power on hot days, when electricity use is highest.
The 13-year-old Riverside power plant in the town of Beloit, fueled by natural gas, was closed in September for regular maintenance.
The facility produces up to 675 megawatts of electricity, enough for 450,000 homes. It has two natural gas-fired combustion turbine generators and a steam turbine generator that uses waste heat from the gas turbines to create more power.
When Alliant tried to turn the plant back on in late November, “the generating station would not restart properly,” spokesman Scott Reigstad said.
The steam turbine was found to have internal damage, Reigstad said, “and the facility cannot run unless the damaged portion is repaired and replaced.”
It will cost $25 million to fix the steam turbine, he said. It is not clear yet if Alliant customers will be asked to pick up all or part of that tab.
“Alliant Energy has submitted a property insurance claim for the repair cost, but coverage has not yet been determined,” Reigstad said. “If insurance coverage applies, we believe the insurance proceeds would cover the vast majority of the repair costs.”
The Riverside plant is heavily used. During the first eight months of 2016, it was operating 63 percent of the time, on average, including four months when it was called into action more than 70 percent of the time, Reigstad said.
“The Riverside Energy Center is one of the most efficient and cost-competitive generators in our Wisconsin generating fleet,” he said.
Alliant had not disclosed the Riverside outage to the public. It came to light when the agenda for Thursday’s meeting of the state Public Service Commission — the state agency that regulates utility companies — was released on Wednesday.
Reigstad said the utility had reported it to the PSC and to MISO, the Midcontinent Independent System Operator, the Carmel, Indiana, organization that handles the flow of electricity on the power grid serving all or parts of 15 states, including Wisconsin, and Manitoba, Canada.
He said the lack of availability of the Riverside power plant will not leave the area short of power. “There’s more than adequate supply. There are a lot of other plants that are not running at full capacity,” Reigstad said.
Riverside’s 25 employees are still fully employed, he said.
Calpine Corp., an independent power development company, built the Riverside power plant; it began operating in 2004. Alliant contracted to buy most of its electricity, and then bought the facility itself in December 2012.
Alliant is building a second natural gas-fueled power plant, West Riverside, next to the existing Riverside plant. It will produce 700 megawatts, enough for 535,000 customers, will cost about $700 million, and should be ready in 2020.
Alliant is installing a 2-megawatt solar energy array at West Riverside as part of the project. Electricity from the solar panels will be used to help power the plant.
The utility also buys power from another solar field on the Riverside property, with maximum capacity of 2.3 megawatts, built by Hanwha Q CELLS, a South Korean company, in 2016.