Ontario Power Generation (OPG) has announced that the second of four reactors that are being refurbished at Darlington Nuclear Generating Station has been reconnected to the province’s electricity grid.

Unit 3 was brought back online on July 18, 169 days ahead of schedule.

The early return of Unit 3 will produce an extra 3 terawatt-hours of energy, enough to power 350,000 homes for an entire year. It will also reduce up to 1 megatonne of greenhouse gas emissions, or the equivalent of taking 300,000 cars off the road for an entire year.

"Through this project, OPG is demonstrating that with detailed planning and preparation, large nuclear projects can be completed not only on-time, but ahead of time and with great quality,” said OPG President and CEO Ken Hartwick. “This would not be possible without the performance, expertise, and commitment from our refurbishment project team, project partners, industry experts, energy professionals, and skilled tradespeople."

Unit 2 was completed in early June 2020. It has since has experienced 529 days of continuous operation. The mark is considered an industry-leading performance for a CANDU reactor post-refurbishment.

The Unit 1 refurbishment project, which is expected to be completed mid-2025, is approximately 60 percent complete and is currently in the reassembly phase. Unit 4, the last of Darlington’s four reactors, will come offline shortly to begin its refurbishment.

Once complete, the refurbished Darlington Nuclear Generating Station will provide more than 30 years of carbon-free power. The project, together with the station’s extended operation, will generate approximately $90 billion in economic benefits for Ontario and create an average of 14,200 jobs annually across the province.

The refurbishment itself is valued at $12.8 billion.

In addition to that work, OPG is also building North America’s first fleet of grid scale Small Modular Reactors at the Darlington Nuclear site. Meanwhile, an assessment for refurbishing the Pickering Nuclear Generating Station will be complete later this year.