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Cooling Toronto Using Lake Ontario 698

An anonymous reader writes "Air cooled by the frigid waters deep in Lake Ontario started bringing relief to buildings in downtown Toronto on Tuesday after the valves were symbolically opened on the multi-million-dollar project. The company says that they have the capacity to air condition 100 office buildings or 8,000 homes - the equivalent of 32 million square feet of building space. They note that the cooling system reduces energy usage, freeing up megawatts from the Ontario's electrical grid, minimizes ozone-depleting refrigerants and reduces the amount of carbon dioxide entering the air."
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Cooling Toronto Using Lake Ontario

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  • by jonbryce ( 703250 ) on Wednesday August 18, 2004 @06:32AM (#9999207) Homepage
    Will this not cause the lake to warm up? What are the envirnmental effects of this? Have they been considered?
    • by PedanticSpellingTrol ( 746300 ) on Wednesday August 18, 2004 @06:34AM (#9999216)
      but then I had a better question: Can it cool my 64-bit prescott?
    • by Rxke ( 644923 ) on Wednesday August 18, 2004 @06:40AM (#9999242) Homepage
      From the article:

      "...Brought to the John St. Pumping Station, the water's cold will be extracted and used to lower the temperature in downtown buildings. The water will then be treated and enter the city's drinking supply...."

      So might be a double whammy, the water isn't directly injected into the lake again.
      • by mdfst13 ( 664665 ) on Wednesday August 18, 2004 @07:09AM (#9999380)
        From where were they getting their drinking water previously? My first guess is that this just substitutes water taken from the bottom of the lake for water that would otherwise be taken from the top. Net change in water levels (vs. not doing this) would thus be negligible.
        • by MightyYar ( 622222 ) on Wednesday August 18, 2004 @08:42AM (#9999860)
          Well, at least in Chicago (on Lake Michigan) they take from the bottom already: See here. []

          Since this has been going on since the 1800's, I think you could probably estimate the environmental impact based on Chicago's experience.

          • by geoswan ( 316494 ) on Wednesday August 18, 2004 @09:58AM (#10000697) Journal
            Your link is interesting. I have one [] too. It took me a minute or two to figure out this page. The map of lake michigan in the lower right hand corner has five lines drawn through it. The five color coded temperature charts each illustrate the temperature at various depths through a slice of the lake. The one closest to Chicago is slice "A", correct?

            There was an interview on the morning news yesterday with a guy who is a big fan of this technology. The interviewer asked him if this technology could be used in other cities on the Great Lakes. Yes, he said. There were various cities where it could be used. Rochester and Milwaukee were two examples he offered. But, he said, it could not be used in Chicago. Presumably because Chicago doesn't have easy access to a deep cold layer.

            Here in Toronto we have always taken our water from deep in the lake too. As you can see from this map [] the depth drops precipitously just off Toronto Island.

            The American fan of this technology was Alec Baldwin, the actor.

            The interviewer next asked him if any of those other cities were considering following Toronto's example. He replied that he was flying to Chicago that afternoon to make a presentation.

      • by Anonymous Coward on Wednesday August 18, 2004 @07:24AM (#9999444)
        "the water's cold will be extracted"

        Hahahahahaha. Perhaps they can keep these rooms lit by extracting the dark from them.
        • by Rui del-Negro ( 531098 ) on Wednesday August 18, 2004 @02:15PM (#10004103) Homepage
          I actually got a darkness pump, but it was so noisy I had to buy a silence generator.

      • by JediTrainer ( 314273 ) on Wednesday August 18, 2004 @08:47AM (#9999907)
        So might be a double whammy, the water isn't directly injected into the lake again.

        I live just north of Toronto, in Markham (part of York Region).

        We get our drinking water from Lake Ontario. All of the GTA (Greater Toronto Area), including the City of Toronto, York Region, Durham, Peel etc, use water pumped from the lake.

        Our sewage is sent back down to Toronto, where it is treated before being dumped back into the lake. In fact, they're in the middle of building an additional set of sewage pipes to further growth in York Region (sort of controversial, because they're affecting groundwater and the Oak Ridges Moraine while they're doing it. Long story - google for details).

        In other words, I don't think it would make any difference, because we've already been drawing our water from there. It's just coming from a different part of the lake.
    • by gowen ( 141411 ) <> on Wednesday August 18, 2004 @06:43AM (#9999257) Homepage Journal
      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.
      • by Analogy Man ( 601298 ) on Wednesday August 18, 2004 @07:22AM (#9999438)
        The scematic does not show the back half of the municipal system (sewer and waste water treatment).

        As a grandson of a plumber I can confirm that the water does eventually end up back in the lake. Rule #1 of plumbing ...water flows down hill.

        The beauty of this implementation is that the incremental warming of the water may actually further save energy if slightly warmer water comes into water heaters. From a thermodynamic standpoint this looks like a very large geothermal system. The economies of scale may make it quite cost effective too.

    • From the "Fact Sheet" on Enwave's site, c /fact

      Will DLWC warm up Lake Ontario?

      * No. Enwave is not extracting from Lake Ontario's water and then directing 'warmer' water back to the lake. The DLWC project has been designed to draw very cold lake water - colder than what the City needs for its water supply - from Lake Ontario. Enwave will extract the extra coldness before the water is sent into the usual water supply system. Water from Lake Ontario is being used
    • by Curtman ( 556920 ) on Wednesday August 18, 2004 @06:45AM (#9999266)
      This has been covered extensively on Discovery Canada, which I watch regularly. Here's a quote that puts this into perspective:

      ...He said environmental studies show the system will cause a temperature increase [each year] equivalent to the heat the lake surface absorbs during seven seconds of sunshine....
      -Toronto cools off using Lake Ontario waters []
    • by VeryProfessional ( 805174 ) on Wednesday August 18, 2004 @06:53AM (#9999310)

      We have to recognise that any interaction we have with the environment is going to have some impact on it. This impact will by definition be negative if we characterise any change to the existing equilibrium as being negative. The smart thing to do is to spread the impact by interacting in lots of different ways on a lower level, rather than abusing a single resource, as we currently do with fossil fuels.

      I applaud what they are doing in Canada. The more alternative energy sources we use, the better.

    • by Catmeat ( 20653 ) <<> <ta> <mtm>> on Wednesday August 18, 2004 @07:25AM (#9999451)
      I suspect a little thing called Winter will have an effect.

      I'm annoyed by all this hysterical nonsense over environmental effects on the lake. Apart from the fact that the heat input is trivial given the size of the lake (do you know what the heat capacity of 393 cubic miles of water is?) People think the lake is not some finite reservoir of coolness - no, it's a heat store, it cools down in the winter people! Consider the hitorical effect of tens of thouands of summers if that were not true.

      In all this ranting, the very real envirnoemental benfits of reducing energy consumption and CO2 emissions get lost in the noise. I'd have expected better from the so-called technically literate.

    • by mpe ( 36238 ) on Wednesday August 18, 2004 @07:35AM (#9999493)
      Will this not cause the lake to warm up?

      Very slightly if the water is fed back into the lake. However water has a high specific heat capacity around 4.2kJ is required to raise one litre of water by 1 degree celsius. The water in this case is comming from a very large lake, so it would take a huge amount of energy input to change the temperature of the lake by any noticable amount.
      There also exist methods of extracting heat from rivers and lakes for heating. So possibly these could be used in winter.

      What are the envirnmental effects of this?

      Most likely considerably less than dumping heat in to the atmosphere, which is how conventional air conditioning works.
    • by Junior J. Junior III ( 192702 ) on Wednesday August 18, 2004 @10:29AM (#10001190) Homepage
      What do you know, now we ARE paying to heat the outside. My dad will flip his wig when he hears about this.
  • Nice :) (Score:5, Insightful)

    by Killjoy_NL ( 719667 ) <slashdot&remco,palli,nl> on Wednesday August 18, 2004 @06:33AM (#9999211)
    This is the kind of stuff I like to see :)

    Ok, it costs a lot of money, but in the long run it has the possibility to save so much more than money: the enviroment.
  • Just two questions (Score:5, Interesting)

    by cyclop ( 780354 ) on Wednesday August 18, 2004 @06:36AM (#9999222) Homepage Journal

    (1). What will happen when the lake water will be warmed up? Ok,it will perhaps take a long time,but...

    (2). How does the energy required for pumping / distributing the water and maintaining pipelines and machinery compares with electrical conditioneers?

    Said that, it looks like a nice idea.
    • by jonbryce ( 703250 ) on Wednesday August 18, 2004 @06:38AM (#9999231) Homepage
      Q1 is a valid concern.

      Q2 is apparently answered in the article. Approx 25% of the energy requirements for electrical air con.
  • by hazman ( 642790 ) on Wednesday August 18, 2004 @06:39AM (#9999234)
    Halliburton, Bechtel and General Electric have signed a multi-billion dollar deal to refrigerate the waters of Lake Ontario.

    The temperature of the lake has inexplicably begun to rise. Algae blooms, moss growing on surronding trees and Corona beer bottles scattered on the shore have alarmed the Canadian Department of the Interior to take swift, albeit expensive action the save the ecosystem of the lake.
  • by Capt'n Hector ( 650760 ) on Wednesday August 18, 2004 @06:46AM (#9999270)
    Several times in recorded history, lakes have "belched" massive amounts of carbon dioxide, killing off not only fish, but people in surrounding areas. Lake Nyos [] is one such example. The circumstances vary, but always involve extremely deep water, saturated with CO2, being shifted to a shallower depth. When this happens, water has a much lower capacity for CO2, and it is released into the air.

    Not that I'm predicting this will happen here, but it's usually best not to heat deep water like that.

    • by Anonymous Coward on Wednesday August 18, 2004 @07:07AM (#9999370)
      I think this is unlikely to be a problem.

      Lakes 'turn over' like this when there has been long-term stratification of the water. Stratification occurs when a layer of warm, less dense, water forms over the colder, denser, lower layers. This is stable since the heat of the sun reinforces the stratification. Only a seasonal reduction in sunlight, or strong winds, can mix the layers.

      Lake Nyos is in a tropical area where there is a permanent, marked stratication due to year-round abundant sunlight. Since mixing of layers is so rare, hug amounts of gas can accumulate in lower layers. This is dangerous should something trigger a rapid breakdown of the stratification - such as the landslide in Nyos.

      In temperate areas stratification is confined to the summer, only then is there sufficient sunlight. In other seasons stratification breaks down and mixing occurs such that a potentially dangerous build up of gas is not possible.
    • by No Such Agency ( 136681 ) <> on Wednesday August 18, 2004 @07:08AM (#9999376)
      They're not sending the warmed (by 8'C) water directly back - it goes to drinking water supply. The CO2 thing IS super-scary though, imagine living by a lake like that (which people still do) :-O
  • by bit4byte ( 210625 ) on Wednesday August 18, 2004 @06:47AM (#9999279)
    According to the site they use the city water supply
    that feeds from the bottom of the lake to cool down
    a closed loop system, which is then used to cool down the offices/homes. No warm water is fed back into the lake. So the lake should not heat up at all.
  • by arska ( 145934 ) on Wednesday August 18, 2004 @06:49AM (#9999287) Homepage
    RTFA !
    Look at the diagram on They warm up the city's drinking water by a few degrees.

    • by frovingslosh ( 582462 ) on Wednesday August 18, 2004 @07:14AM (#9999397)
      Actually, it's unlikely that the city was drawing it's drinking water from this deep before. They were almost certainly taking it from a point higher up and warmer. So the city drinking water may not be warmer at all as a result of this; it might even be cooler. And, since the lower water can hold more CO2, it might be slightly carbonated! (Look for the interesting side effects when somewhat more acidic carbonated water is flowing through old pipes.)

      On the other hand, since the cold water is being taken from the lake now rather than warmer water, the thermal barrier between the warmer top water and the lower cold water may slowly lower (and it is a very sharp layer, not the gradual drop in temperature you might expect). This may indeed have some effect, but that doesn't seem very likely.

      They could have gone the simpler and more direct route of just building a power plant that used the difference in tempersture between the cold bottom water and the top water to pump up that water and generate electricity. Such plants have been proven to work with ocean water, and should be even simpler in an environment without salt water's effects. I'm assuming they didn't because in Toranto that top water would also get pretty cold in the winter. Still, I don't expect they will need much air conditioning in the winter anyway, so a seasonal power plant might have been as good or better of an idea.

    • They are not "warming up the city drinking water", they are using the warmer water for city usage, which is different.

      Anyone who lives around Lake Ontario knows how freaking cold that lake is, even when it's high 90's out, humid as hell, you can turn on your cold water and get freezing water out all summer, it's because this is a large deep lake. I live in a different city (still on the great lakes) yet the cold water is noticable warmer in the summer months due to the lake that it draws from being so sha
  • by carndearg ( 696084 ) on Wednesday August 18, 2004 @06:49AM (#9999288) Homepage Journal
    The London Underground is doing this as well, though they are doing it with the ground water they pump out of the tunnels. If it relieves the sweaty hell of a crowded Tube train it gets my vote!

    Here's the BBC's story about it [].

  • by starvingartist12 ( 464372 ) on Wednesday August 18, 2004 @06:49AM (#9999292) Homepage

    The Toronto Star's coverage [] has more info about Alec Baldwin's participation in the launch of the Deep Lake Water Cooling system:

    Hollywood heavyweight Alec Baldwin heaped praise on Canada's "forward-thinking" approach to energy today at the launch of a new system that uses the frigid waters of Lake Ontario to cool downtown office buildings.

    The system is nothing short of a "miracle," gushed Baldwin, 46, the square-jawed star of blockbuster films like The Hunt for Red October and Ghosts of Mississippi who moonlights as an environmental activist.

    "This is an important signal you are sending not only to your fellow countrymen but to the world," Baldwin told the gathered crowd.

    "There's no project on a municipal level this size that's been attempted or has been executed before like this."

    Unconventional thinking seemed to be at the heart of today's event, which looked like a Hollywood premiere, complete with a blasting techno soundtrack, fog machine, and bizarre floor show of twirling gymnasts contorting themselves around a large ring suspended from the ceiling.

  • by Bertie ( 87778 ) on Wednesday August 18, 2004 @06:54AM (#9999316)
    Er, how? What does this mean? Cold's just the absence of heat, the only way to "extract" it is to heat something up.
  • by T.Hobbes ( 101603 ) on Wednesday August 18, 2004 @06:54AM (#9999318)
    For me, at least, this is what renewables should be about: finding a local source of economical renewable energy, and applying the appropriate technology to make it useful. The key thing, though, is that the methods change depending on what's availible locally.
  • by MrKane ( 804219 ) on Wednesday August 18, 2004 @06:57AM (#9999328)
    John St. Pumping Station has obviously found some way of overcoming The Second Law of Thermodynamics as:
    'the water's cold will be extracted and used to lower the temperature in downtown buildings'.

    Unit for Cold anyone?
  • Another link (Score:5, Informative)

    by Kernel Kurtz ( 182424 ) on Wednesday August 18, 2004 @07:00AM (#9999346) Homepage
    From the CBC

    No registration required; 17 /enwave_040817.html

  • by Shivetya ( 243324 ) on Wednesday August 18, 2004 @07:24AM (#9999446) Homepage Journal
    I thought they were strictly water/evaporation based when it came to large scale building cooling? Hence I don't see the claim of reducing refrigerants. Now where are they determining reduction of CO2 into the air? Is this from the power savings?

    I know that "real" portable cooling units have no refrigerants (the corp I work for resells some).

    I can see the savings from power, but I still don't like the idea of sucking cold water from the bottom of a lake. It would seem to me you could upset the balance and possibly cause the lake to flip thereby releasing tons on CO2 - something which happened in Africa, which did kill a lot of people.
  • Show me the numbers (Score:4, Interesting)

    by Stephen Samuel ( 106962 ) <samuel AT bcgreen DOT com> on Wednesday August 18, 2004 @07:28AM (#9999457) Homepage Journal
    This is one of those things that looks good when you start -- but what happens when everybody starts doing it? What I'd love to see is some info on the volume of water extracted from the lake for this project vs. the volume of water in the lake. This would give geeks like me a much better chance of being able to figure out for ourselves just how much this is going to affect Lake Ontario and how much the basic idea is going to affect the lake as the idea becomes more popular (as I expect it will).
  • It's a GREAT Lake (Score:5, Interesting)

    by Titusdot Groan ( 468949 ) on Wednesday August 18, 2004 @07:38AM (#9999498) Journal
    Just a reminder folks, Lake Ontario is one of the Great Lakes, it's REALLY big. Like you can't see the other side of it from the shore line. Big. Really big. Like it's huge. Average depth of 86 meters, surface area of almost 19000 km2. Big.

    Did I mention it's big?

    Plus water turns over automatically at 4C (that's the temperature when water is it's coldest). Lake Ontario is not meromictic and has a natural turnover anyways.

  • by JBMcB ( 73720 ) on Wednesday August 18, 2004 @08:32AM (#9999777)
    Geothermal has been around for a long time. There are closed loop systems that put the condenser coil underground, and open-loop systems that use streams (ideal) and ponds (somewhat less ideal)

    The General Motors Technical Center in Warren, MI has been using open-loop cooling for decades, using the large pond on the campus as an open-ended evaporator. The fishes that live in it don't seem to mind.

    There's a nice picture here:
    (Pictured is the "Design Dome" the design building to the right, general engineering in the buildings above the pond, and the Cadillac, Chevrolet, Pontiac and mid-lux buildings beyond)
  • by samjaffe ( 805855 ) on Wednesday August 18, 2004 @09:02AM (#10000127)
    Cornell University recently did this with the deep water of Cayuga Lake ( ). As you can imagine, it caused quite a spirited debate in such a liberal town as Ithaca. In the end it was approved and the University is gauging the environmental effects very carefully( cts/Lake%20Source%20Cooling/lake_source_cooling_mo nitoring_p.htm). So far, there's been little effect. Although some ( might disagree. I would like to point out to the concept's cheerleaders that there's nothing wrong with asking questions about the fundamental ecological effects of our engineering projects. Those questions should be answered thoroughly and carefully. Yes, global warming appears to be a severe problem, however let's not replace it with a bigger problem by stifling debate and rushing in with an ABCO2 (Anything But Carbon diOxide) attitude that might be more harmful than the disease.
  • I hate this (Score:3, Interesting)

    by nightsweat ( 604367 ) on Wednesday August 18, 2004 @09:40AM (#10000459)
    I don't hate that the Canadians are doing this sort of work, but I do hate that we're not. Look, I'm in Chicago, a huge American city with the slogan "the city that works" and where we decided that the river flowed the wrong way, so we changed it. Why the hell aren't we putting in something like this?

    These days those quasi-socialists have it all over us...

  • by PrebleNY ( 797307 ) on Wednesday August 18, 2004 @09:41AM (#10000461)
    A similar lake source cooling project was implemented at Cornell while I was there. They tore up half the campus laying 36" pipe down to the nearby lake. Of course this project is much larger (with a larger lake as well), but from what I have heard the Cornell project has been a success despite the hand wringing of the radical environmentalist. The Toronto plan seems to be even better as they are not discharging the water directly back to the lake (as they do in Ithaca) but are processing it for drinking water. more information on the Cornell LSC website
  • Geothermal Heat Pump (Score:3, Informative)

    by InterGuru ( 50986 ) <jhd.interguru@com> on Wednesday August 18, 2004 @09:54AM (#10000633) Homepage
    For those of us who do not live near a body of water, you can get considerable savings from a Ground Source (Geothermal) Heat Pump. This system uses an air conditioner/heat pump which uses ground water as a heat sink in the summer and a heat source in the winter. Because ground water is a steady temperature ( usually 50-60 degrees F) you get an energy saveing of 20-40% over conventional systems which use the air as a heat source and sink. The air is hot in the summer and cold in the winter, which is exactly what you don't want.

    You can find more infomation here [] and here []

  • by geoswan ( 316494 ) on Wednesday August 18, 2004 @10:05AM (#10000820) Journal
    There is one advantage of this system that I haven't seen mentioned yet.

    Have you ever had an errand in the downtown office area, and walked through a big blast of hot air?

    Not only does this save energy. But because those downtown buildings are not using conventional air conditioners for cooling, they are not dumping megawatts of waste heat into the outside air. I read that the use of this technique should reduce the local ambient air temperature on the downtown streets, where it is used, by several degrees.

    As a pedestrian I welcome this.

  • by swb ( 14022 ) on Wednesday August 18, 2004 @10:19AM (#10001020)
    I've always wondered why you couldn't use a similar system in a residential area. We have a lake behind our house that's about a mile around and about 8 feet deep on average; couldn't we (at least the immediate lakeshore residents, if not a larger amount of neighbors) use the lake water to augment our air conditioners?

    You'd dump warm water back in, but this could be augmented somewhat by holding tanks and underground piping that cooled it back to ground temperature. If the lake was man-made, the environmental effect would be essentially nil, and you'd only have to worry about thermal calculations.

    This might not make sense for retrofitting, but what about for new developments? People like lake/park areas, and there's no reason that a cooling pond couldn't be framed in a naturalistic setting.

    I suppose it all comes back to commercial viability; it'd take a more expensive air conditioner capable of combining water cooling with electrical compressor cooling, the "community" would be responsible for the cooling pond and piping, and the electrical savings might not matter.
    • by rebelcool ( 247749 ) on Wednesday August 18, 2004 @12:02PM (#10002467)
      the capital investment tends to be prohibitive for residential applications.

      Like its much more energy efficient to use chilled water a/c with a large central cooling tower. Then pump chilled water out to each home for use in chilled water a/c units. Large office and university campuses do this. But, at several million dollars, the investment is just too much for developers.

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