CANDU 850

The CANDU 850 is a Generation II pressurised heavy water reactor from AtkinsRéalis (Candu Energy). 4 units are operating and 0 are under construction, out of 4 on record.

Darlington, the last CANDU station built in Canada and the largest single-design CANDU batch, four units of 934 MWe. It went into service between 1990 and 1993 at roughly four times its original budget, a cost overrun that ended new nuclear construction in Ontario for thirty years. Its mid-life refurbishment, running through the 2020s, has been the counter-example: delivered close to schedule and budget. The BWRX-300 now under construction at the same site is the province's first new build since.