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Most of downtown Toronto is cooled by lakewater - enwave energy provides district cooling for most of the major buildings in the downtown core. This includes 151 Front St., one of the major datacentres in the area. See here

Toronto already uses cold water cooling for air-conditioning many of its office towers in the downtown core and has for many years. (see: http://www.enwave.com/dlwc.php). Unless winter never visits Canada again, this is cold body is self-replenishing.

That's been done in Toronto

http://www.enwave.com/enwave/dlwc/

the cold water is the city's drinking supply, taken from deep in Lake Ontario, and its used to cool a closed-loop that in turn cools some of Toronto's office buildings.

If you had a 80 kilometres, or so, of tubing you could pump cold water from Lake Erie or Ontario through the copper coil and cool your room that way. Like what them folks at Enwave are doing in downtown Toronto. ;-)

See http://www.enwave.com/enwave/dlwc/
Anyone who has been to Dubai (I spent a few years there) knows that desalinization in such large capacities is both financially and technically sustainable... Irigation is a no brainer... Creating surplus energy, though ??? That does not sound plausible...

There are several office buildings in downtown Toronto that are cooled via cold water pumped from lake Ontario. http://www.enwave.com/enwave/view.asp?/dlwc/energy

The same sort of thing exists in Toronto.

• Cleaner drinking water for Toronto residents because the water used in the cooling process comes from a deeper part of Lake Ontario. This cold lake water does not touch the water in Enwave's closed chilled water supply loop; it only uses the coldness through a heat exchange process and is then sent to the citizens of Toronto through the City's normal potable water system.
  - enwave fact sheet

Not the easiest thing to find on the site, but the Enwave history page shows that the Environmental Assessment for the Deep Lake Water Cooling project was approved in 1998. I would expect that this study is the basis for the environmental benefits claimed for the project.

Not the easiest thing to find on the site, but the Enwave history page shows that the Environmental Assessment for the Deep Lake Water Cooling project was approved in 1998. I would expect that this study is the basis for the environmental benefits claimed for the project.

The graphic on Enwaves site shows that the water taken out of the lake is for the potable supply which won't make it back into the lake until people have used it. The water will be a little warmer when it comes out of the first exchanger but as it runs through the pipes underground the temp equalizes to the ground temp which if I remember correctly is close to the 12.5 C anyway.

More info:
http://www.city.toronto.on.ca/water/deep_lake/
Video:
http://www.enwave.com/enwave/news/?s=dlwc&ReleaseI D=53

Posted AC cuz I modded here (torstenvl)

postnumber % 1000000 == 0 ?

It's just a dumbed-down way of saying "energy stored in used coolant water is transferred to cold water from the lake". If you look at the diagram in the article, it's pretty clear: they run the cooling water alongside the lakewater to bleed (is that the right term?) the heat out, then send the heated lakewater out to the city as tap water--in essence "extracting the cold" from the lakewater and "storing" it in the cooling system.

Man, I can't believe I'm getting sucked into this moronic, paranoiac debate.

1 - Lake Ontario doesn't freeze over, but it does have some surface ice in midwinter. Ice implies a surface temp at or below 0 degrees c. Right?

2 - Having lived next to another sizeable lake (Lake Champlain, which typically does freeze over), and as an EXPERT in hydrodynamic modelling, I can assure you that that niggling little physics detail about water having maximum density at... (drum roll) 4 degrees C is accurate. However, twice a year, lakes like Ontario have all their water churned about as ambient average temp falls below 4 degrees C, then as ambient temp rises above 4 c. Wierd, but true. Frankly, seiche's are wierder.

3 - So, as winter gets cold enough, any water not AT 4 degrees C rolls to the surface, where it is... say it with me... chilled by the Toronto winters. Before any ice is made, everything in the lake chills to 4 degrees C (this is my biggest oversimplification here, since inversion layers can exist in large water bodies. It doesn't matter in the overall calcs to follow, since all I was interested in showing is the mechanics for recharge of the cold zone).

4 - The thermal mass of Lake Ontario (one site says 86 m average depth, x 19,000 km^2 in area... 19,000,000,000 x 86 x 100 ^3 cm^3 per meter x 1 degree c x 0.0039683 btu's per calorie x .000000293 btu's per megawatt hour = 2* 10 ^9th Megawatt hours needed.

The Fact Sheet on Enwave's site says they're gonna free up 59 megawatts. Now, I should be able to disregard a part of this as an efficiency improvement (electricity for cooling is gawdawfully inefficient, compared to non-compressive heat exchangers like this'll use), but I'll eat the inefficiency because that's the nice guy I am. 59 x 24 x 365 (megawatt-years to megawatt-hours) gets us *finally* to matching units. If I haven't completely bolluxed the calculation, we're looking at a capability of handling 3673 of these facilities. Or, the temp of Lake O going up 1/3673 of a degree.

Oh. Yay. The little fishies aren't even going to notice this. In fact, there's room for exporting this capability and if we're willing to warm Lake O by a few degrees I think it'd take care of the AC demands of most of North America, if them clever Canadians can just figure out a way to export this.

When she's working hard, the sun 'wastes' enough energy warming up dirt and water around the world to fuel our needs a thousandfold over. When she's not paying attention (at the poles, nights and winters), earth's radiating it off like gangbusters.

The risk of us boogering up our surroundings when we do BIG things is a valid one. But not here, not yet.

We've reached the point where we're influencing the world in several spots: cfc's, pesticides, acid rain, particulate emissions, garbage, animal populations, etc. etc. etc.

But this isn't one of them. As a side joke, I bet there are a few million Toronto residents that'd be more than happy to let the thermal average temp of Lake O go up 30 degrees, just for the lake-effect warmth it'd impart on their town each winter and the ability to swim without turning blue in midsummer. Back during a nasty winter ('93), a favorite bumper sticker of mine was 'Another Vermonter *for* global warming'.

Rock on Toronto & Enwave.com

No it won't, because the water used to cool the air is the same water that would be extracted anyway, to provide potable water to the city. See this schematic. Notice the warm water is not returned to Lake Ontario.