• Nuclear power currently provides about 50 per cent of Ontario's electricity supply and has positioned Ontario as one of the cleanest electricity grids in the world.
• According to Ontario's Independent Electricity System Operator (IESO), the province's demand for electricity is forecast to increase significantly by 2050.
• The Darlington refurbishment project was completed by over 6,000 Ontario workers over the course of the project, including members of:
  • Society of United Professionals
  • Power Workers' Union
  • Canadian Union of Skilled Workers
  • Electrical Power Systems Construction Association
  • United Association
  • International Brotherhood of Electrical Workers
  • Ironworkers/Rodmen
  • Millwrights
  • Boilermakers
  • Carpenters
  • Labourers
  • Sheet Metal/Roofers
  • Operating Engineers
  • Cement Masons
  • Painters
  • Plasterers
  • Teamsters
  • Brick and Allied Craft Union/Tile & Terrazzo
• OPG captured approximately 8,000 lessons learned over the course of the project that were applied throughout the refurbishment to save time and money, which will benefit other large nuclear projects, including the Pickering Nuclear Generating Station Refurbishment Project, refurbishment and new build at the Bruce Nuclear Generating Station, and construction of the first small modular reactor (SMR) in the G7 at the Darlington site.
• In September 2025, the Canadian Nuclear Safety Commission (CNSC) granted OPG a 20-year licence for the Darlington Nuclear Generating Station, authorizing OPG to operate the station until November 30, 2045, which is the longest nuclear operating licence granted to date in Canada.

"Ontario is showcasing world-class leadership in nuclear energy through the completion of one of the biggest refurbishment projects our province has ever seen. This is a major made-in-Canada milestone that not only supported our industries and workers throughout the refurbishment process, but will sustain thousands of good-paying jobs, generate tens of billions of dollars for our economy, and protect Ontario against economic uncertainty for decades to come. And it will provide our industries with the assurance that Ontario is open for business and is well-equipped to power the future."

- Sam Oosterhoff, Associate Minister of Energy-Intensive Industries

"Delivering the largest nuclear refurbishment in the world four months ahead of schedule and $150 million under budget is a real testament to the strength, skills, and innovation of Ontario's highly trained workers and our nuclear supply chain. Like the early completion of work at another Darlington unit last year, this early finish demonstrates that Ontario can deliver large, complex, low-carbon infrastructure on time and on budget. As we continue to lead the largest nuclear expansion in North America, including the first small modular reactors in the G7, we can have confidence in our ability to power Ontario's future with reliable, clean nuclear energy for generations to come."

- Rudy Cuzzetto, Parliamentary Assistant to the Minister of Energy and Mines

"Ontario's successful refurbishment of the Darlington Nuclear Generating Station is a remarkable achievement that strengthens our province's energy security for decades to come. Delivering this world class project ahead of schedule and under budget demonstrates what Ontario can accomplish when industry, workers, and government work together. This investment will provide clean, reliable power for 3.5 million homes while supporting thousands of good paying jobs across Ontario."

- David Smith, Parliamentary Assistant to Minister of Energy and Mines

"The on-time and on-budget refurbishment of the Darlington Nuclear Generating Station has secured thousands of skilled jobs in Clarington. With all four refurbished units back online, Darlington will generate enough energy to power 3.5 million homes for the next 30 years, supporting continued economic growth in Durham and across Ontario."

- Todd McCarthy, Member of Provincial Parliament, Durham

"Under the leadership of Premier Ford and Minister Lecce, our government is setting the standard for how major energy projects should be delivered. Completing this project four months ahead of schedule and $150 million below budget demonstrates Ontario's ability to deliver major infrastructure projects that support reliable, affordable energy for families and businesses in Whitby, Durham Region, and across the province."

- Lorne Coe, Member of Provincial Parliament, Whitby

"Today marks a major milestone with the completion of the Darlington Refurbishment Project. This achievement highlights Ontario's skilled workforce, who delivered this critical project ahead of schedule. Workers from our region and across Ontario are the backbone of this success. By protecting good local jobs, we strengthen our communities and build lasting economic growth close to home. Projects like this demonstrate that Ontario can continue to lead in clean, reliable, and affordable energy, while ensuring the benefits are felt in our communities for generations to come."

- David Piccini, Member of Provincial Parliament, Northumberland-Peterborough South

"The world is watching Darlington right now, as we celebrate the successful completion of the refurbishment, which finished ahead of schedule and under budget. This accomplishment is rare in the international nuclear sector and speaks to how capable our nuclear crews are. By pulling off this major win, all while building the first grid-scale small modular reactor (SMR), Ontario's work sets Canada apart as a global energy superpower."

- Adrian Foster, Mayor, Municipality of Clarington

"On behalf of the Municipality of Port Hope, I offer congratulations to our OPG neighbours in Darlington. Completing the Darlington Unit 4 nuclear reactor project ahead of schedule and under budget is commendable, allowing the benefits of this investment to be realized sooner and reinforcing OPG's role as a global leader in clean energy. I also applaud the Province of Ontario for delivering this project as part of its 25-year integrated energy plan and for its continued commitment to long-term energy solutions. We look forward to more exciting energy announcements in the near future."

- Olena Hankivsky, Mayor, Municipality of Port Hope

"The completion of Unit 4 is another example of the world class expertise we have right here in Durham Region, the Clean Energy Capital of Canada. Darlington's successful refurbishment supports thousands of local jobs and strengthens Ontario's supply of clean, reliable power for decades to come. Our community is proud to play a leading role in delivering the energy that keeps Ontario strong and competitive."

- John Henry, Regional Chair and Chief Executive Officer, Municipality of Durham

"Aecon is immensely proud to have completed Unit 4, the fourth and final unit of this critical, decade-long project at OPG's Darlington Nuclear Generating Station. Working alongside OPG and our project partner Candu Energy, an AtkinsRéalis company, the capability, discipline, and commitment of our Darlington team and Ontario's skilled tradespeople drove unit-over-unit improvements in safety, schedule, and cost performance. Delivering the world's largest nuclear refurbishment project safely and five months ahead of schedule provides a model for major nuclear projects on a global scale."

- Jean-Louis Servranckx, President and CEO, Aecon

"Completing the refurbishment of the Darlington Nuclear Generating Station ahead of schedule and under budget is a testament to the skill, discipline and dedication of Ontario's unionized workforce, and to the strong collaboration between labour, employers, and government, with special mention to Ontario Power Generation and Minister of Energy and Mines, Stephen Lecce. LiUNA members are proud to deliver clean, reliable power that supports good jobs, strengthens our economy, and secures Ontario's energy future for generations to come."

- Joseph Mancinelli, International Vice President and Canadian Director, LiUNA

"The completion of the Darlington Unit 4 reactor refurbishment construction ahead of schedule and under budget clearly demonstrates what Ontario's nuclear sector can deliver. With OPG's leadership and a highly skilled, province-wide supply chain, Ontario is well positioned to advance the next phase of nuclear development, supporting long-term jobs, economic growth, and a reliable electricity system for decades to come."

- Julie O'Driscoll, Executive Director, Ontario's Nuclear Advantage

"Ontario has entered a period of unprecedented electricity demand and it's critical that we build the system needed to power the province's future. Congratulations to Ontario Power Generation on completing this major refurbishment ahead of schedule and under budget. We look forward to connecting the clean, reliable nuclear energy that OPG produces to homes, businesses and industries across Ontario through our transmission network. Together, OPG and Hydro One are helping build a stronger, more resilient energy future for the province."

- David Lebeter, President and CEO, Hydro One

"This milestone is the result of years of project management excellence and sustained collaboration across Ontario's nuclear sector. Completing the Darlington refurbishment ahead of schedule and under budget demonstrates the strength of Canada's nuclear industry, while helping position Canada as a global leader in nuclear refurbishment and life-extension projects. It also underscores the industry's ability to deliver clean, reliable power that supports long-term economic growth."

- George Christidis, President and CEO, Canadian Nuclear Association

"The completion of the Darlington Unit 4 refurbishment is a major milestone for Ontario's electricity system and a strong example of how long-term planning and execution deliver results for ratepayers and the economy. Bringing this unit back online ahead of schedule and under budget strengthens system reliability, supports skilled jobs across the province, and ensures Ontarians continue to benefit from clean, dependable nuclear power for decades to come."

- Vince Brescia, President and CEO, Ontario Energy Association

"Darlington Unit 4 shows what is possible when nuclear projects are well planned, rigorously engineered, and precisely executed. With Aecon as our construction and execution partner, this refurbishment was completed ahead of schedule and under budget, extending the reactor's operating life by more than 30 years -- a clear demonstration of the performance and durability designed into CANDU technology. With all four units now refurbished, Darlington stands as proof that Candu Energy has the expertise, supply chain, and proven technology to deliver large-scale nuclear projects, underscoring the value of building a fleet of CANDU reactors to support a resilient domestic clean energy future."

- Sandy Taylor, President and CEO, Candu Energy

"Delivering a major nuclear project under budget and ahead of schedule shows what's possible when innovation, skilled workers and operational excellence align. It reinforces our vision of an innovative nuclear industry as an integral part of Canada's clean energy future, strengthens public confidence and underscores the role nuclear energy plays in economic sustainability and energy security."

- Jessica Linthorne, President and CEO, Nuclear Innovation Institute

"The completion of the Darlington refurbishment project is a tremendous achievement and a testament to the dedication, expertise and collaboration of Ontario Power Generation, its project partners, and the thousands of skilled workers who brought this complex project to completion ahead of schedule and under budget. For more than a decade, the Darlington refurbishment project has generated significant economic benefits for Clarington, neighbouring communities and beyond - supporting jobs, local businesses, and long-term prosperity. Our community is proud to be home to a project that will continue powering Ontario's economy and communities for decades to come."

- Bonnie Wrightman, Executive Director, Clarington Board of Trade

"Ontario's nuclear workers have once again shown the exceptional skill, dedication, and professionalism that keep our province powered. The highly skilled unionized workforce is at the heart of this success and play a crucial role in delivering clean, reliable energy for all Ontarians. Their achievements reflect the strength and ability within the nuclear sector that delivers large, complex projects in a fiscally and timely manner during a time of rising electricity demand and the need for new nuclear investment."

- Andrew Clunis, President, Power Workers Union

"Congratulations to OPG on their success on the Darlington Unit 4 refurbishment. Bruce Power is pleased through our collaboration agreement with OPG to help ensure Ontario continues its world leading track record of on time on budget large scale nuclear refurbishments including those at the Bruce site."

- Pat Dalzell, Vice President Corporate Affairs, Bruce Power

"Completing Darlington Unit 4 ahead of schedule and under budget is a major achievement. Ironworkers are proud to have helped deliver one of the world's most complex nuclear refurbishments safely and to the highest standards. This project proves that investing in skilled workers delivers lasting economic value and clean, reliable power for generations."

- James Hannah, President, Ontario Ironworkers District Council

"From a local business perspective, the completion of the Darlington Unit 4 refurbishment highlights the value of reliable energy infrastructure in supporting regional economic stability and growth. Ontario's nuclear sector continues to create skilled jobs and strengthen local supply chains, and communities like Port Hope see real opportunity in thoughtful, responsible development connected to this industry."

- Andrew Hall, CEO, Port Hope and District Chamber of Commerce

"The Canadian Association of Small Modular Reactors applauds the completion of the refurbishment of the Darlington Unit 4 nuclear reactor. This milestone reinforces confidence in Canada's nuclear sector and reflects Ontario's leadership, as well as the depth of Canadian collaboration, engineering, and project execution expertise. This track record will be essential as Canada advances its next wave of nuclear projects, including the deployment of the first SMR in the G7."

- Erveina Gosalci, Founder and CEO, Canadian Association of Small Modular Reactors

"The Society of United Professionals is extremely proud to see another successful nuclear refurbishment delivered on time and under budget. The success of these enormous projects is possible because of the tireless efforts of the engineers, analysts, physicists, front-line managers, coordinators, program leads, and other professionals who work at Ontario's nuclear facilities. It is thanks to these unionized workers that Ontario continues to be a world leader in nuclear energy. The Society is grateful to the Government of Ontario for its commitment to maintaining the province's nuclear fleet and its support of our nuclear professionals."

- Rebecca Caron, President, Society of United Professionals

"Darlington's ahead of schedule and under budget refurbishment stands as a remarkable achievement for Ontario and a powerful demonstration of what Canada's nuclear sector can achieve. This accomplishment is a testament to the excellence of the entire team, including Ontario Power Generation, Atkins Réalis, the Canadian Nuclear Safety Commission, and the many suppliers and technical partners from throughout the nuclear value chain, as well as to the support and the visionary leadership of the government of Ontario. This success is more than a milestone; it is a foundation. The industrial capabilities, the supply chain strength, and the project discipline proven at Darlington will be essential as Canada and Ontario move forward with new nuclear deployment, from next generation SMRs to large scale reactors. The world is watching, and Darlington shows that Canada is ready to lead the next era of clean energy with nuclear as its anchor."

- Dr. Sama Bilbao y León, Director General, World Nuclear Association

"We're incredibly proud to have played a role in the Darlington refurbishment - a project that demonstrates what's possible when a strong, experienced nuclear supply chain comes together with a shared focus on safety, quality and delivery. This work supported local jobs and skilled trades while strengthening Ontario's secure energy future, and it proves the nuclear supply chain is ready to take on new nuclear projects."

- Tim Gitzel, CEO, Cameco Corporation

"Completing the Darlington Unit 4 refurbishment ahead of schedule and under budget is a major achievement for Ontario and Canada's nuclear supply chain. It reflects strong collaboration across government, industry, Indigenous partners, and a highly skilled Ontario workforce. The lessons learned from this project will carry forward -- supporting future nuclear projects delivered to the same high standards and providing clean, reliable power and long-term economic benefits for decades to come."

- Ivette Vera-Perez, President and CEO, OCNI

"With a global reputation of nuclear projects going over budget and exceeding schedule, the Canadian nuclear industry has once again made history by doing the exact opposite. Boilermakers are proud of their part and contribution to the completion of the world's largest nuclear refurbishment ahead of schedule and under budget. Today announcement by Minister Lecce continues to highlight the unique benefits of our homegrown nuclear technology, our strong domestic supply chains, and our incredible industry partners. Through their commitment to investing in the province, the Ontario Government and OPG have done an incredible job in showcasing the advantages of our world-class CANDU technology."

- Jonathan White, Director, International Brotherhood of Boilermakers

"Today, we extend our heartfelt congratulations to the entire Darlington team on the successful completion of the Unit 4 refurbishment project. Achieving this milestone five months ahead of schedule and under budget is a testament to your dedication, hard work and expertise. We are honoured to have supported this project which reinforces Ontario's commitment to clean, reliable energy while paving the way for growth in nuclear capacity to meet the climate challenge and create jobs in our province."

- John MacQuarrie, President, Commercial Operations, BWXT

"Completing Darlington Unit 4 is a win for Ontario's economy and its clean-energy future. Finishing early and under budget is a global calling hard for our nuclear leaders and workers. Reliable, clean power builds business confidence, and grows Ontario's long-term competitiveness."

- Daniel Tisch, President and CEO, Ontario Chamber of Commerce

"EPSCA is proud of its members whose professionalism and dedication made the safe and successful completion of Darlington Unit 4 possible. This project strengthens Ontario's electricity system and helps protect reliable, affordable power for families and businesses. Their work shows what Ontario can achieve when labour and industry come together and sets a strong standard for future infrastructure work in the province."

- Caitlin Gascon, General Manager, EPSCA (Electrical Power Systems Construction Association)

"Darlington Unit 4's early return to service is great news for Ontario. Nuclear generation is a critical part of Ontario's diverse electricity supply mix, and this facility's early return means it will be available to help keep our grid reliable for Ontarians during the summer when demand is at its highest. We are proud that the IESO's Operations team was able to support today's announcement by working in close collaboration with OPG and the Ontario government as they complete another refurbishment project ahead of schedule and under budget."

- Lesley Gallinger, President and CEO, Independent Electricity System Operator

"OPG's completion of Darlington Unit 4 ahead of schedule and under budget is a strong example of what disciplined execution can deliver -- grounded in decades of refurbishment experience, a coordinated supply chain, and a highly skilled workforce. This achievement also signals that OPG has the leadership and delivery capability to build the first Small Modular Reactor in the G7, applying the same rigorous commitment to safety, quality, and reliability throughout its development. GE Vernova Hitachi is proud to be collaborating with OPG to deploy our BWRX-300 technology at Darlington, and we're optimistic about what we can deliver together for communities and the broader energy system."

- Lisa McBride, Country Leader, Small Modular Reactors, GE Vernova Hitachi

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