Ontario Power Generation said construction has been completed four months ahead of schedule and $110 million under budget on the estimated $9.4 billion decade upgrade of the four-unit Darlington nuclear plant, 45 miles east of Toronto. Final tests are being carried out on its 878MW Unit 4 reactor which is scheduled to return to full commercial operation by the end of the month.
The latest project marks the completion of what Ontario Power Generation says is the largest renewal project in the world.
The reactors, all 878 MW each, began commercial operation in the early 1990s, with Unit 2, the first upgraded unit returning to service in June 2020, Unit 3 in July 2023 and Unit 1 in November 2024. The Canadian-based project consortium was led by Aecon Group Inc. and AtkinsRéals. BWXT Canada. According to Ontario Power Generation, the work included the replacement of 1,920 fuel lines and 3,840 feed pipes.
“Through this project, we have shown the world that complex nuclear projects can be completed successfully, ahead of schedule and on budget.” said Nicolle Butcher, President and CEO of Ontario Power Generation. “Our experience in this renewal, and the thousands of lessons we’ve learned, will serve as a foundation as we move forward into the future of nuclear.”
The upgrade extends the plant’s life to 2055, Ontario Power Generation said.
Last November, Ontario’s provincial government also gave the agency formal approval to begin upgrading four nuclear power units totaling about 2.1 GW at the Pickering nuclear power plant, also near Toronto, and expanding its capacity to about 2.2 GW.
the beloved $19.75 million project, also awarded to Aecon-ArkinsRealis as the EPC contractor to begin work in 2027, it includes the replacement of the 48 steam generators, which Ontario Power Generation says is the first scope of work of its kind for its Candu reactor fleet. The project also includes the construction of a 1.5 km deep water intake system to secure the colder cooling water, described as an infrastructure element not found in the original design of the plant. Four other units have been closed and are scheduled to be decommissioned.
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Ontario Power Generation also won approval last spring from the province and the Canadian Nuclear Safety Commission to begin construction on the first of four BWRX-300 small modular nuclear reactors in Darlington, awarding a $329 million contract to AtkinsRéalis unit CANDU Energy for the first to be operational in 2030. It is expected to generate about 1.2 GW of power.
“In a world of uncertainty, our government is doubling down on nuclear technology and Canadian workers, with 96 per cent of investment benefiting Ontario’s supply chain,” said Stephen Lecce, national minister of Energy and Mines, “Canada is among only six nations with civilian nuclear technology, but we are number one in building, operating and renewing projects on time and under budget.”
Japan’s stalled nuclear restart finally clicks
Meanwhile, on February 9, Japanese nuclear experts from Tokyo Electric Power Co. (TEPCO) restarted a key unit of the world’s largest nuclear power plant – the nearly 8 GW one. installation of seven Kashiwazaka-Kariwa reactors near Tokyo, after an earlier attempt was called off due to a control rod warning. “We will continue to demonstrate our commitment to safety as a priority at the Kashiwazaki-Kariwa Nuclear Power Plant through our actions and results,” TEPCO said in a statement.
Japan shut down all its nuclear power plants after an earthquake and tsunami in March 2011 caused some meltdown at its Fukushima Daiichi facility, also owned by TEPCO. It is now being retired.
The 1.3GW Kashiwazaka-Kariwa unit is the 15th reactor restarted as Japan aims to become carbon neutral by 2050 and reduce its use of fossil fuels, particularly imported liquefied natural gas. The plant complex now includes a 50-foot-tall wall to protect against tsunamis, along with improved safety and emergency power systems to meet new standards set by Japan’s Nuclear Regulatory Authority.
The country’s prime minister, Sanae Takaichi, who was re-elected in a landslide victory on February 8, sees nuclear power as a long-term domestic energy source and economic driver for the country, aiming to supply 20 percent by 2040. She supports accelerated development of next-generation reactors and fusion technology. noting that “homegrown energy, especially nuclear power and perovskite solar cells, will be critical.”
