OVERKILL
$100 Site Donor 2021
If you ever take a look at Qinshan nuclear power plant in China, the CANDU units don't look much different from anywhere else in the world:
The same is the case for Point Lepreau in New Brunswick:
Yet, if you look at ANY of the active nuclear plants in Ontario, which all have multiple units and a common turbine hall, you'll notice a distinct feature that sets them apart, which is a large standalone structure that looks like a huge containment vessel. This is the vacuum building.
In Ontario, since the plants were all going to be built relatively near large population centres, it was decided that the safety systems would be augmented by the fitment of a negative pressure containment system, plumbed into all the units, that could suck all the air out of a given unit in the event of an issue that might otherwise result in a release.
This is how close Pickering nuclear is to the city of Pickering:
So, at all three of our large multi-unit sites, the vacuum building(s) are present. Pickering, being an in-line arrangement, has a single vacuum building for all 8 units. You can see it just below units 1 and 2.
Darlington, which is just up from Pickering, is 4 units with a single vacuum building:
Bruce A has its own vacuum building:
As does Bruce B:
You'll notice the design of the newer Darlington vacuum building is a tiny bit different, with it having a rounded top.
Every 10 years, scheduled for one of the shoulder seasons where demand is low, the vacuum building must be inspected. This requires taking all the units offline, which is a considerable drop in electricity production. In the case of Bruce A, that's around 3,200MW, or very similar to the current active nameplate capacity of the Pickering facility. It was scheduled for a 28 day outage but they were able to complete it in a significantly shorter timeframe due to extremely favourable results.
This is what that outage looked like:
Gas and hydro usage (lots of hydro right now due to the freshet) increased considerably to cover this loss of capacity and emissions predictably went up with the gas usage. This was a good "dry run" for what Ontario's grid will look like if Pickering is allowed to retire in 2025 (which we are currently trying to change the course on).
The vacuum buildings were built using one giant continuous pour. Here are some pics from when Darlington was built:
The same is the case for Point Lepreau in New Brunswick:
Yet, if you look at ANY of the active nuclear plants in Ontario, which all have multiple units and a common turbine hall, you'll notice a distinct feature that sets them apart, which is a large standalone structure that looks like a huge containment vessel. This is the vacuum building.
In Ontario, since the plants were all going to be built relatively near large population centres, it was decided that the safety systems would be augmented by the fitment of a negative pressure containment system, plumbed into all the units, that could suck all the air out of a given unit in the event of an issue that might otherwise result in a release.
This is how close Pickering nuclear is to the city of Pickering:
So, at all three of our large multi-unit sites, the vacuum building(s) are present. Pickering, being an in-line arrangement, has a single vacuum building for all 8 units. You can see it just below units 1 and 2.
Darlington, which is just up from Pickering, is 4 units with a single vacuum building:
Bruce A has its own vacuum building:
As does Bruce B:
You'll notice the design of the newer Darlington vacuum building is a tiny bit different, with it having a rounded top.
Every 10 years, scheduled for one of the shoulder seasons where demand is low, the vacuum building must be inspected. This requires taking all the units offline, which is a considerable drop in electricity production. In the case of Bruce A, that's around 3,200MW, or very similar to the current active nameplate capacity of the Pickering facility. It was scheduled for a 28 day outage but they were able to complete it in a significantly shorter timeframe due to extremely favourable results.
This is what that outage looked like:
Gas and hydro usage (lots of hydro right now due to the freshet) increased considerably to cover this loss of capacity and emissions predictably went up with the gas usage. This was a good "dry run" for what Ontario's grid will look like if Pickering is allowed to retire in 2025 (which we are currently trying to change the course on).
The vacuum buildings were built using one giant continuous pour. Here are some pics from when Darlington was built: