nuclear-news

Lepreau nuclear headaches could add up to an extra $150M

NB Power says it won’t know the true costs until plant comes back online in December after an eight-month shutdown

John Chilibeck  •  Local Journalism Initiative reporter, Oct 28, 2024 Journal: https://tj.news/new-brunswick/lepreau-headaches-could-add-up-to-an-extra-150m

NB Power expects the troubled Point Lepreau nuclear plant to be back up and running in December, about 140 days after serious problems were first discovered.

The repairs and replacing the lost electricity could cost New Brunswick ratepayers $150 million, based on testimony provided earlier this year by senior executives at the public utility.

In a news release Monday, NB Power said the total costs won’t be known until the plant near Saint John is back in operation. The utility is also considering making an insurance claim to protect the public and businesses from punishing costs.

“Our team has been working diligently, with the support of national and international experts, to assess and address the situation,” stated spokesperson Dominique Couture in the release. “This has been a very complex task, and NB Power left no stone unturned in understanding the problem and the repair options.”

During a summer rate hearing before the New Brunswick Energy and Utilities Board, Craig Church, a chief modeler for the public utility, told the quasi-judicial body that replacing the 660 megawatts of energy lost at the Candu reactor, one of the most important plants in its generating system, costs on average $900,000 a day.

The repair work and replacement power did not figure into rate hearings in which NB Power asked for the highest hikes to electrical rates in generations – close to 20 per cent over two years. A decision is still pending with the board.

During those summer hearings, NB Power estimated the repair work would cost $20 million and replacing energy $51 million, for a total of $71 million.

But that was an estimate only up to Sept. 1, roughly 48 days of the unplanned outage. Extending that timeline to Dec. 1 would add another 91 days, just when temperatures plunge and electrical costs go up.

The $900,000 a day estimate was an average only, suggesting the costs could escalate to at least $150 million.

The Point Lepreau Nuclear Generating Station has been offline since April 6, when NB Power undertook a planned, 100-day maintenance outage.

But when getting ready for starting the plant back up in July, workers identified a critical issue within the main generator, located on the non-nuclear side of the plant.

It turns out it wasn’t even in an area that was part of the maintenance work.

The culprit was a damaged stator bar in the generator, one of the long devices inside the big round machine and a stationary part of the rotor.

The experts began probing further and after testing all 144 bars, found five others showing signs of serious deterioration.

“An independent investigation has determined that the cause of this issue is a manufacturer’s defect that occurred during the maintenance of the generator in 2010,” NB Power stated. “We made the decision to repair all six bars while the station is offline to ensure continued safe operations and prevent potential issues in the future.”

It wasn’t a simple job. To access the stator bars, workers had to meticulously disassemble part of the generator assembly, including the removal of the machine’s rotor.

“The stator bars and other internal components are delicate and strict manufacturer’s precautionary measures must be followed,” Couture wrote. “We are pleased to report that repairs have been completed on all six stator bars and that the generator reassembly is underway. This involves several verification steps and thorough testing to ensure that all components are precisely aligned and secured.”

NB Power said once the components are ready, in the coming weeks, it will begin start-up activities at the massive plant, including equipment checks and testing protocol. The utility anticipates a full return to service in December. That would mean the unplanned outaged lasted about 140 days, with Lepreau offline for a total of about eight months.

The true costs won’t be released until the plant is back in service, NB Power stated. Couture said the utility is examining every option to reduce costs for its customers, including looking at an insurance claim.

“We are pleased that the station will be back online for the winter heating season to ensure New Brunswickers have the energy they need when they need it,” Couture wrote. “We are committed to safety and operational excellence and will continue to keep the public informed.”

October 30, 2024 - Posted by Christina Macpherson | business and costs