Toronto The Well | 174.03m | 46s | RioCan | Hariri Pontarini

This might have been answered previously but what is the purpose of this cistern?

It's a giant heat exchange system, to expand Enwave's cold-water cooling system. The current system cools buildings by warming the city's tap water. That option is basically exhausted (we don't want the tap water to get any warmer in the summer), so to cool more buildings this cistern will be filled with water, which will dissipate the heat from the buildings at the Well, and other buildings in the future. I think the excess heat goes into the ground, but am a bit unclear on the mechanism.
 
It's a giant heat exchange system, to expand Enwave's cold-water cooling system. The current system cools buildings by warming the city's tap water. That option is basically exhausted (we don't want the tap water to get any warmer in the summer), so to cool more buildings this cistern will be filled with water, which will dissipate the heat from the buildings at the Well, and other buildings in the future. I think the excess heat goes into the ground, but am a bit unclear on the mechanism.

Interesting. Funny how 2,000 year old Roman Methods are still being used today.
 
Crane from the well visible from the Rogers centre
F31B5A84-7727-448C-ADE2-9D121A5C4A9F.jpeg
 
It's a giant heat exchange system, to expand Enwave's cold-water cooling system. The current system cools buildings by warming the city's tap water. That option is basically exhausted (we don't want the tap water to get any warmer in the summer), so to cool more buildings this cistern will be filled with water, which will dissipate the heat from the buildings at the Well, and other buildings in the future. I think the excess heat goes into the ground, but am a bit unclear on the mechanism.
May I ask you where you got this information. Because it is not accurate... and rather causing confusion to other less informed members.
As was posted in other links, Enwave is using chill water from Lake Ontario to provide cooling to certain buildings in the core. They do not use "tap water" as mentioned in your post.
 
May I ask you where you got this information. Because it is not accurate... and rather causing confusion to other less informed members.
As was posted in other links, Enwave is using chill water from Lake Ontario to provide cooling to certain buildings in the core. They do not use "tap water" as mentioned in your post.
The water is drawn from deep in Lake Ontario, passed through a heat exchanger, then treated and sent to the drinking water system, so it is tap water in a sense (or pre-tap water).

My understanding of the purpose of this storage tank is this (100% my own speculation, caveat emptor, etc.):
Demand for heating and cooling is spiky. Cooling, particularly: offices are occupied mostly from 9-5, which is also the hottest part of the day. Based on the size of the pipe and the capacity of the boiler / heat exchanger, there is a capacity limit in terms of square footage of office space that can be heated or cooled. But much of this capacity goes unused at night when offices are unoccupied. The purpose of this storage tank is to add essentially a giant thermal battery: the existing equipment can be used to pre-heat or pre-cool the water overnight, then during the day, the embodied energy can be extracted from the water. This means Enwave can expand the system (apparently up to 20 million square feet) while using the existing infrastructure.
 
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May I ask you where you got this information. Because it is not accurate... and rather causing confusion to other less informed members.
As was posted in other links, Enwave is using chill water from Lake Ontario to provide cooling to certain buildings in the core. They do not use "tap water" as mentioned in your post.
I was pulling from this Star article:

" Enwave is unusual in that it uses drinking water as the coolant. Other systems dump heated water back into the lake from which it’s drawn — leading to concerns about environmental damage. Flowing the heat into the drinking water supply avoids that problem."

It's a closed heat exchange system, so the tap water isn't actually the coolant, it's just where the "waste heat" ends up, instead of immediately back in the lake. That was the constraint that necessitated this tank (no more heat sink capacity in the municipal water supply).
 

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