OVERKILL
$100 Site Donor 2021
As has been mentioned in my Ontario Nuclear Update threads, OPG is retiring Pickering A this year, which was the first large scale nuclear plant in Canada, consisting of 4x experimental CANDU units that share little with what was constructed later. Rated at 515MWe each, this was 2,060MW of capacity and the largest plant we had ever built at the time. The 4x Pickering A units had a surprisingly good track record early in their lives, but simplifications were made in the subsequent plant (Bruce A) to reduce cost and improve ease of maintenance.
The Pickering A units lack a fast-acting fully independent secondary safe shutdown system, as they were built with a moderator dump (a CANDU can't maintain fission without a heavy water moderator) as the second safe shutdown system, but this is not considered sufficiently "fast acting" under current regulations. Ontario Hydro was required to retrofit a 2nd fast acting safe shutdown system to the units as part of their late 90's Pickering A restart project (later OPG, after the breakup) and ultimately, they went with the cheapest possible option: adding more control rods and splitting them into groups, which essentially means that Units 1 and 4, as Units 2 and 3 were not restarted due to McGuinty wanting to go full Energiewende, basically have "1.5" fast acting safe shutdown systems, and this is a pain for OPG every time they go to renew the license, as it receives considerable extra deliberation from the CNSC.
With Pickering A only being two operational units of a 4-unit plant (poor economics), the decision was made to shutter the A units, rather than refurbish them (they've been running for over 50 years without a refurbishment) at the end of 2024, while Pickering B, whose units are based on the standard CANDU 6 design, will receive a full refurbishment starting in 2026.
On September 13th, 2024 Pickering A unit 1, which entered service in June of 1971, hit 600 days of uninterrupted generation, 23 days shy of its best run:
It is supposed to retire at the end of this month, followed by Unit 4 later this year, as Darlington 4 comes back from refurbishment.
Pleas have been made to OPG to run the unit longer, to beat its previous record and let it go out on a high note. Hopefully OPG listens.
SOP is to stop refuelling operations and the old girl will slowly decline in output as no new fuel is shuffled into the core, fading away until she's disconnected from her generator, allowed to cool, defuelled and then laid up like her sisters.
While it is possible that after the Pickering B refurbishment, the potential refurbishment and resurrection of the A units will be considered, it's highly unlikely, as it would be a higher risk project and two of the units haven't run in over 30 years (though they are materially mostly intact, no decommissioning work has been done but parts have been poached for units 1 and 4).
Once Pickering A is retired, Bruce A, which entered commercial service in 1977, will be the oldest operating nuclear plant in Canada. It is licensed to run to 2064, but Bruce Power's James Scongack has recently stated that 2064 was just an arbitrary date they plucked from the ether for licensing and plans are to run the plants significantly longer than that.
The Pickering A units lack a fast-acting fully independent secondary safe shutdown system, as they were built with a moderator dump (a CANDU can't maintain fission without a heavy water moderator) as the second safe shutdown system, but this is not considered sufficiently "fast acting" under current regulations. Ontario Hydro was required to retrofit a 2nd fast acting safe shutdown system to the units as part of their late 90's Pickering A restart project (later OPG, after the breakup) and ultimately, they went with the cheapest possible option: adding more control rods and splitting them into groups, which essentially means that Units 1 and 4, as Units 2 and 3 were not restarted due to McGuinty wanting to go full Energiewende, basically have "1.5" fast acting safe shutdown systems, and this is a pain for OPG every time they go to renew the license, as it receives considerable extra deliberation from the CNSC.
With Pickering A only being two operational units of a 4-unit plant (poor economics), the decision was made to shutter the A units, rather than refurbish them (they've been running for over 50 years without a refurbishment) at the end of 2024, while Pickering B, whose units are based on the standard CANDU 6 design, will receive a full refurbishment starting in 2026.
On September 13th, 2024 Pickering A unit 1, which entered service in June of 1971, hit 600 days of uninterrupted generation, 23 days shy of its best run:
It is supposed to retire at the end of this month, followed by Unit 4 later this year, as Darlington 4 comes back from refurbishment.
Pleas have been made to OPG to run the unit longer, to beat its previous record and let it go out on a high note. Hopefully OPG listens.
SOP is to stop refuelling operations and the old girl will slowly decline in output as no new fuel is shuffled into the core, fading away until she's disconnected from her generator, allowed to cool, defuelled and then laid up like her sisters.
While it is possible that after the Pickering B refurbishment, the potential refurbishment and resurrection of the A units will be considered, it's highly unlikely, as it would be a higher risk project and two of the units haven't run in over 30 years (though they are materially mostly intact, no decommissioning work has been done but parts have been poached for units 1 and 4).
Once Pickering A is retired, Bruce A, which entered commercial service in 1977, will be the oldest operating nuclear plant in Canada. It is licensed to run to 2064, but Bruce Power's James Scongack has recently stated that 2064 was just an arbitrary date they plucked from the ether for licensing and plans are to run the plants significantly longer than that.
