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Darlington Nuclear’s Unit 1 sets world record for continuous operation

Unit 1 at OPG’s Darlington Nuclear Generating Station has set a new world record for continuous operation of a nuclear power reactor at 963 days and counting.

A view of the Unit 1 turbine hall at Darlington Nuclear GS. Unit 1 has set a new world record for continuous operation by a nuclear power reactor.
A view of the Unit 1 turbine hall at Darlington Nuclear GS. Unit 1 has set a new world record for continuous operation by a nuclear power reactor.

On Tuesday, Sept. 15, the clean power stalwart broke the previous record of 962 days set by India’s Kaiga power station in December 2018.

Online since Jan. 26, 2018, Darlington’s Unit 1 has not needed to be taken out of service for maintenance or repair for more than two and a half years.

“This extraordinary achievement is another proud moment in Darlington’s history,” said Sean Granville, OPG’s Chief Operating Officer. “Unit 1 produces clean, affordable and reliable electricity, keeping our air clean with no carbon or smog emissions. Its continued strong performance is a direct reflection of the station’s reliability and the efforts of our dedicated employees.”

On its journey to rewriting the history books, Unit 1 has set several new benchmarks for the nuclear industry.

Late last year, the 878-megawatt (MW) unit set a generation record for the 3,512 MW station located in Clarington when it hit 688 days of consecutive operation on Dec. 15.

On Thursday, July 9, the reactor set a new Canadian and North American nuclear record with 895 straight days of consecutive operation. Pickering Nuclear’s Unit 7 held the previous record at 894 days.

Now, Unit 1 owns the world record.

That’s remarkable performance from a unit that was commissioned almost 28 years ago on Nov. 14, 1992. Less than a year from now, the reactor will undergo a refurbishment that will extend its operating life by another 30 years.

Aside from generating clean, affordable power, Darlington’s four reactors will also soon produce two life-saving medical isotopes, Cobalt-60 and Molybdenum-99. The former is used to sterilize single-use medical devices while the latter is used in medical diagnostics and imaging.