CNSC issues 20-year operating licence for Darlington

Press Release

September 25, 2025

Licence term reflects OPG’s commitment to safety and operational excellence

CLARINGTON, ON – The Canadian Nuclear Safety Commission (CNSC) has announced its decision to renew Ontario Power Generation’s (OPG) licence for the Darlington Nuclear Generating Station (DNGS) for a 20-year term. This decision authorizes OPG to operate the DNGS to November 30, 2045, making it the longest nuclear operating licence granted in Canada.

The current licence expires on November 30, 2025.

The longest-ever licence term for a Canadian nuclear station reflects the strong performance of the Darlington station, the proficiency of our highly skilled workers, and OPG’s continued commitment to safety and operational excellence. Under this licence, Darlington will continue to safely and reliably produce electricity to help meet Ontario’s energy needs for decades to come.
Nicolle Butcher
OPG President and CEO

The Darlington Refurbishment Project commenced in 2016 and is now nearing completion earlier in 2026 than its original schedule and on budget, including COVID-19 pandemic and inflation impacts. During refurbishment, the team replaced major components, completed inspections, and introduced modifications to improve the station. This work will ensure safe and reliable operation of the station throughout the licence term and beyond.

The CNSC held a two-part public hearing in March and June 2025 to consider the application from OPG and written submissions from CNSC staff and intervenors.

Key facts

• Located within the treaty and traditional territory of the Williams Treaties First Nations and the Municipality of Clarington in Durham Region (70 km east of Toronto), OPG’s Darlington Nuclear Generating Station is a four-unit facility responsible for generating over 20 per cent of Ontario’s electricity needs.

• OPG has extensive experience operating nuclear stations safely and reliably for more than five decades. The DNGS has proven to be a safe, reliable and important source of energy for the Province of Ontario while meeting constantly growing energy needs.

• Darlington reactors are not only crucial for reliable electricity generation – they are also capable of producing potentially life-saving medical isotopes used in targeted cancer treatment therapies, medical diagnostic imaging, and other health, food, and security applications.

Quotes

“The longest-ever licence term for a Canadian nuclear station reflects the strong performance of the Darlington station, the proficiency of our highly skilled workers, and OPG’s continued commitment to safety and operational excellence,” said Nicolle Butcher, OPG President and CEO. “Under this licence, Darlington will continue to safely and reliably produce electricity to help meet Ontario’s energy needs for decades to come.”

About OPG

As Ontario’s largest and one of North America’s most diverse electricity generators, OPG invests in local economies and employs thousands of people across Ontario. OPG and its family of companies are advancing the development of new low-carbon technologies, refurbishment projects and electrification initiatives to power the growing demands of a clean economy. Learn more about how the company is delivering these initiatives while prioritizing people, partnerships and strong communities at opg.com.

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For further information, please contact:

OPG Media Relations
416-592-4008 or 1-877-592-4008

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