Darlington Refurbishment includes significant safety enhancements
When the Canadian Nuclear Safety Commission agreed to allow OPG to proceed with its life-extension program at Darlington Nuclear Generating Station, it wasn’t simply on the basis of refurbishing reactor parts – there was also a requirement to update and install new safety systems to further enhance defences at a plant already boasting an excellent safety record.
“We committed as part of the Environmental Assessment to install a number of new systems focused on the management of low-probability, beyond-design-basis events,” said Dietmar Reiner, Chief Project Officer and Senior Vice President, Enterprise Projects. “Unit 2’s refurbishment provided an opportunity to implement enhancements to ensure continued safe operation through its extended life and ensure it conforms to the same codes as more modern nuclear power plants.”
OPG’s operating experience at the plant and advances in technology since Darlington was first constructed were all taken into consideration for these upgrades, Reiner said.
Safety improvements included installation of a third, more robust emergency power generator to provide multiple layers of back-up in case of power loss. Having an extra generator in place also allows existing generators to be taken off-line for maintenance to further enhance reliability.
Additionally, fire protection systems were inspected and updated to meet modern regulatory codes and standards and to ensure reliability through the plant’s 30-plus years of extended life resulting from the refurbishment.
Major component replacement, such as reactor fuel channel assemblies and primary heat transport feeder piping, will also help ensure Darlington’s on-going safe operation.
Many of these improvements increase safety and flexibility for all four units at Darlington, but to meet Environmental Assessment conditions, these enhancements had to be completed before Unit 2 returned to service.
“Our refurbishment-related overhauls and replacements mean greater reliability from both an operational and safety perspective,” said Reiner. “It will ensure Darlington remains among the best in the nuclear industry through its extended life.”