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Using the Sea To Cool Your Data Center

1sockchuck writes "We haven't yet seen signs of the Google Navy of seagoing data centers that use the ocean for power and cooling. But data center developers are planning to use sea water air conditioning in a new project on the island nation of Mauritius in the Indian Ocean. Cold water from deep-sea currents would be piped ashore to be used in a heat exchanger for the data center facility. A similar system has been used to replace the chillers at Cornell University, which draws cold water from Lake Cayuga. The Cornell system cost $50 million, but has slashed cooling-related energy usage by 86 percent."

40 of 194 comments (clear)

  1. interest prospect by Icegryphon · · Score: 3, Insightful

    But what are maintenance costs and lifespan of such a piece of equipment,
    I can't image Saltwater not eating the hell out of all the piping.

    1. Re:interest prospect by sopssa · · Score: 5, Funny

      I can't image Saltwater not eating the hell out of all the piping.

      Yeah, thats the real problem. I hope we discover such metal soon so we can get boats and ships in the oceans too.

    2. Re:interest prospect by FooAtWFU · · Score: 2, Interesting

      You keep the saltwater on one side of a heat exchanger; it minimizes the vulnerable piping, and helps a lot. Heck, you could build the big seawater pipes out of concrete.

      --
      The World Wide Web is dying. Soon, we shall have only the Internet.
    3. Re:interest prospect by Useful+Wheat · · Score: 4, Informative

      A low carbon stainless steel such as the 316 series should be more than sufficient for any piping. Moving parts such as pumps and impellers would be made of titanium for optimum durability and minimum downtime. Lifetime of the pipes is assured by simply adding a small corrosion allowance to the wall thickness (maybe 1/4"), and checking for corrosion once in a while to make sure its not being destroyed faster than you predict. Although that may sound ridiculous, I promise you it is both fairly common and not that hard. Seawater is the lifeblood of many power plants, and it doesn't take a miracle to handle it.

    4. Re:interest prospect by initdeep · · Score: 5, Insightful

      seawater is the lifeblood of every naval nuclear power plant, and as someone who was in the navy and in charge of the heat exchangers attached to a naval nuclear power plant, i can assure you it is a big deal and a LOT of time and maintenance is put into preventing corrosion and the associated leakage in piping that a heat exchanger utilizes.
      In order to have efficient heat exchange between two moving fluids, you need a very thin wall and you need it to be clear of any and all corrosion. This means a lot of time and effort, not too mention chemicals are used.
      For a mobile naval vessel, there is no other option, so the cost isn't an issue.

      For a land based cooling system, it is an issue because there very well may be less expensive alternatives.

      Not too mention the possible ramifications (good and bad) of discharging all of the heated water back into the marine ecology.

    5. Re:interest prospect by digitalunity · · Score: 2, Informative

      Most steel ships are painted to prevent corrosion. Paint is a thermal insulator. Coating the inside of your heat transfer pipes with a thermal insulator is like masturbating with sandpaper - it might work, but it doesn't work well.

      Aluminum is a great thermal conductor and is saltwater resistant with the 6061 and 6063 alloys. Galvanic corrosive action does occur though, but this can be avoided with careful attention to construction methods and avoiding direct metal to aluminum contact.

      --
      You can't legislate goodness. Let each to his own destiny, by will of his freely made choices.
    6. Re:interest prospect by Gonoff · · Score: 2, Interesting

      They manage well in the Sydey Opera House. They keep the salt water out of their system and heat exchange to fresh water which they circulate.

      To keep the corrosion low, they use sacricicial anodes http://en.wikipedia.org/wiki/Sacrificial_anode . These are also used on ships, oil rigs and pipelines - probably more things too. This is nothing new. I believe the opera house was finished in 1974 so they are using well tested technology here.

      --
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    7. Re:interest prospect by MicktheMech · · Score: 2, Informative

      Aluminum is a great thermal conductor and is saltwater resistant with the 6061 and 6063 alloys.

      The 6000 series alloys are also extremely expensive compared to steel and more importantly difficult to weld, even compared to stainless.

    8. Re:interest prospect by david.given · · Score: 4, Informative

      A low carbon stainless steel such as the 316 series should be more than sufficient for any piping.

      Stainless steel is prone to pitting corrosion when exposed to water containing chlorides. 316 series stainless steel is significantly corroded by concentrations of chlorides above 1000ppm (ref). Standard sea water at 3.5% salinity has a chloride concentration of about 20000ppm (ref).

      Stainless steel works rather like aluminium when it comes to preventing corrosion; the surface oxidises very rapidly to form a passive coating, protecting the bulk of the metal from oxygen. In water, this only works if (a) the water contains enough oxygen to passivate the metal, and (b) the water won't then dissolve the coating as soon as it forms. In particular, this means that stainless steel is not suitable for things like marine bolts, because under the bolt head the water will quickly lose all its oxygen and you'll get corrosion. It also means you have to be very careful in sea water as the salts can strip off the chromium oxy passive layer.

      316 stainless is considered 'marine grade', but only just. In particular, it's unsuitable for warm sea water, as this makes the water vastly more corrosive. So you probably don't want to use it for coolant pipes.

      And I haven't even mentioned electrolytic corrosion yet. Sea water is one of the most corrosive environments on the planet, and dealing with corrosion is one of the biggest problems when working with it.

    9. Re:interest prospect by 10Neon · · Score: 2, Interesting

      This sounds a lot like the arguments about microwave radiation from radio towers and microwave ovens: it seems to overlook the massive amounts of energy arriving from the sun.

      Every square inch of ocean (minus those under clouds at a given moment) is constantly absorbing radiation. The fact that there are even oceanic currents- huge, fast-moving masses of water, moving for thousands of miles, is a testament to the kind of energy the ocean deals with all the time. If there's ever a problem with humans overheating a patch of water, it's because they're not spreading the heat far enough, or placing it somewhere where currents can move it off. When it comes to energy, "human scale" and "planetary scale" are still quite different from one another.

      Somewhat related: http://en.wikipedia.org/wiki/Ocean_thermal_energy_conversion
      If deep, cold water is pumped up, you could actually achieve a local net cooling, if you wanted.

      --
      The Guide is definitive. Reality is frequently inaccurate.
    10. Re:interest prospect by treeves · · Score: 4, Informative

      I hope you intended to mod the comment down. What do you think ship's propulsion plant cooling systems and condensers use for cooling water and what do you suppose they are made of? Yes, seawater flows through metal tubes on every ship on the sea. There are saltwater corrosion-resistant alloys, like some bronzes, Monel, and others. Nobody paints the inside of condenser tubes on a nuclear-powered ship, and the primary reason is NOT because paint is a thermal insulator. It's just not necessary and it would be a PITA to do it.

      --
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    11. Re:interest prospect by ruewan · · Score: 2, Interesting

      The electricity company in Barbados has been doing this for as long as I can remember. They use sea water to cool their equipment. There equipment seems to last. Most of their intake pipes are fiberglass. The place where they pump the water back out to see is a favourite bathing spot for locals. I wonder about the long-term environmental impact of this. The water there smells funny but it feels really good.

    12. Re:interest prospect by treeves · · Score: 2, Informative

      Not to worry. Aluminum isn't used in ship seawater piping - try Ni-Al bronzes, Ni-Cu alloys, like Monel. There are probably some stainless steels in use and titanium alloys but those are more expensive too. One thing the GP got right is that galvanic corrosion is a big concern in seawater piping systems and heat exchangers. Sacrificial zinc anodes are used frequently to prevent it.

      --
      ...the future crusty old bastards are already drinking the Kool-Aid.
    13. Re:interest prospect by bronney · · Score: 2, Funny

      Anything over 1200 grit should work pretty well. You end up with a shiny rod too!

  2. Although it uses less electricity, not "green" by Useful+Wheat · · Score: 5, Informative

    Although this solution is certainly "low power" by no means should it be considered to be entirely green. I work as an engineer on many projects that involve sea water, and when you're using it for a cooling source you typically need to inject some sort of chemical to sterilize the water to keep growths off your heat exchangers (barnacles are sort of a pain in the ass in your exchangers). As a result, using sea water for large scale cooling operations is prohibited in large regions of the United States (specifically the gulf coast) mostly over concerns that the large amounts of warm bleached water will damage the ecosystem. Although, that issue aside, using the ocean as a cooling medium is a great idea, and has been used reliably by power plants for many years.

    1. Re:Although it uses less electricity, not "green" by jollyreaper · · Score: 2, Insightful

      Although this solution is certainly "low power" by no means should it be considered to be entirely green. I work as an engineer on many projects that involve sea water, and when you're using it for a cooling source you typically need to inject some sort of chemical to sterilize the water to keep growths off your heat exchangers (barnacles are sort of a pain in the ass in your exchangers). As a result, using sea water for large scale cooling operations is prohibited in large regions of the United States (specifically the gulf coast) mostly over concerns that the large amounts of warm bleached water will damage the ecosystem. Although, that issue aside, using the ocean as a cooling medium is a great idea, and has been used reliably by power plants for many years.

      So maybe it would be more environmentally sound to run a closed loop out to the current to cool the water and bring it back? Salt water is nasty, evil shit.

      --
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    2. Re:Although it uses less electricity, not "green" by Spy+der+Mann · · Score: 3, Funny

      Salt water is nasty, evil shit.

      You should've seen it when it was filled with primordial soup a thousand million years ago, and then came the primitive lifeforms, eeew!

  3. Cold water cooling by diodeus · · Score: 4, Interesting

    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.

  4. Re:So could... by aicrules · · Score: 2, Funny

    It would then be under the jurisdiction of pirates of the real kind.

  5. Warm Water Discharge by guyfawkes-11-5 · · Score: 2, Informative

    Powerplants use this frequently, it's a great idea until the amount of warm water discharged begins affecting the discharge site. I can't imagine a data center requiring the amount of cooling that a powerplant would need.
    The EPA required some modifications to a similar system for a powerplant in PR a few weeks ago.
    http://www.waterworld.com/index/display/article-display/1830526029/s-articles/s-waterworld/s-industrial-water/s-wastewater/s-2009/s-08/s-epa-requires_new_pipe.html

  6. Re:Environmental impact, anyone? by caerwyn · · Score: 4, Informative

    The Cornell project was actually incredibly controversial prior to beginning operation for exactly that reason. Studies since have shown that any detrimental effects are negligible, though, so the controversy has died down in recent years. (I was at Cornell when the system went into operation and for a few years afterward)

    --
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  7. Re:So could... by aicrules · · Score: 2, Insightful

    That really depends on what treaties the ....zzzz put myself to sleep even trying to explain it.sorry

  8. Computer cause global warming! by ipoverscsi · · Score: 2, Funny

    I'm not too sure about the anthropogenic global warming, but I'm starting to come around to it. Earlier my contention was that global warming scientists are causing global warming, but I'm beginning to think that maybe -- just maybe -- computers in general might be the cause. I mean, if computers are having to pump cold water from the ocean depths to cool computers, that's gotta be dumping a lot of heat back into the ocean, right? Right...?

  9. Most of downtown Toronto is cooled by lakewater by insanewombat · · Score: 3, Informative

    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

    1. Re:Most of downtown Toronto is cooled by lakewater by Archon-X · · Score: 2, Interesting

      Slightly offtopic, but still geeky.

      The enwave tunnels were being extended even as late as mid last year (I'm assuming it's either finished, or close to it).

      I managed to get in and pay them a visit while construction was stopped for the winter. It was a fascinating peek into their system - the tunnels are placed in overlapping crosses from as far North as Bay and Elizabeth, as far south as Lakeside. I assume the cross pattern is to give as much coverage as possible.

      For the intruiged, here are a few snaps.

      http://www.ninjito.com/2008-02-29a/qx-to-2.jpg [bottom of entry shaft, entry point for TBM]
      http://www.ninjito.com/2008-02-29a/qx-to-3.jpg [Inside an unformed tunnel - the cooling pipes are laid in the bottom, then covered with concrete, leaving the top semicircle as walk access]
      http://www.ninjito.com/2008-02-29a/qx-to-1.jpg
      http://www.ninjito.com/2008-02-18/qx-to-3.jpg [close up of the trains they used for construction]

  10. Re:global warming anyone? by ShadowRangerRIT · · Score: 2, Insightful

    Generally speaking, humans are not believed to have the capacity to directly affect the global climate on any significant scale. We can only affect it indirectly by altering the amount of heat received from the Sun and the amount emitted back into space. While the heat emitted by these projects may have localized effects, it's highly unlikely to produce any global climate effects. I suppose there is a tiny chance of disrupting ocean currents, but that's indirect, and only redistributes heat, it doesn't affect the global average. Global warming also redistributes heat, but the global average also climbs, it's not zero sum (within the Earth's atmosphere; everything is zero sum eventually).

    --
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  11. Re:Environmental impact, anyone? by Trepidity · · Score: 3, Informative

    Not a subjective judgment in either direction, but for what it's worth, this paper abstract quantifies the heat imparted to Lake Cayuga as "equivalent to an additional two hours of sunlight each year".

  12. Cooling from the sea! by spun · · Score: 2, Interesting

    "Welcome, humans! I am ready for you! Fish, plankton, sea greens and cooling from the sea. Fresh as harvest day. Overwhelming, am I not? Are you, too, startled? Am I too removed from your kin?"

    --
    - None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
  13. Environmental Concerns by Laptopdude · · Score: 2, Insightful

    Raising the temperature of a body of water by even a few degrees can have disastrous consequences; from outright killing species, to producing algal blooms that deplete oxygen levels (and then kill species). I mean, think about it. Water resists temperature change much more than air, so a sudden increase is bad news to creatures that just aren't made to deal with it. Also, a recent study has found that increased carbon dioxide levels are making marine life more susceptible to fluctuating temperature and oxygen levels.

    But, of course, just one place in the ocean using this method isn't going to have that much effect. It's if and when this cooling strategy starts to catch on that we have to worry about affecting our environment, and weigh the consequences of air conditioning (fossil fuel emissions) versus heat pollution.

    1. Re:Environmental Concerns by RobVB · · Score: 5, Informative

      The total mass of the oceans is about 1.4*10^21 kg. The total mass of the atmosphere is about 5*10^18 kg. That means the oceans weigh about 300 times as much as the atmosphere.

      The heat capacity of water is about 4000 J * kg ^ -1 * K ^ -1. The heat capacity of air is about 1 kJ * kg ^ -1 * K ^ -1, or about 1000 J * kg ^ -1 * K ^ -1.

      So since there's 300 times as much water as there is air, and the heat capacity of water is 4 times larger, heating up the atmosphere by 1200 degree Celsius would take the same amount of energy as heating up the oceans by 1 degree Celsius. This may not prove or disprove your point, I just started thinking about numbers when you said "raising the temperature of a body of water by a few degrees".

      --
      I'd rather you rationally disagree than irrationally agree.
    2. Re:Environmental Concerns by Khashishi · · Score: 2, Insightful

      I knew the environment would come up. Of course, pretty much anything humans do is going to be deleterious to the environment. But put things in perspective. It's more thermodynamically efficient to transfer heat to the ocean directly, rather than burn fuel to create electricity to power a heat pump which is used to transfer heat into the air. The power plant also needs to be cooled, either by evaporating large amounts of water in cooling towers, or by transferring heat to an ocean or lake. Which do you think is better for the environment?

    3. Re:Environmental Concerns by mujadaddy · · Score: 2, Funny

      heating up the atmosphere by 1200 degree Celsius would take the same amount of energy as heating up the oceans by 1 degree Celsius.

      Wow. Let's do that!

      --
      Populus vult decipi, ergo decipiatur...
      "Force shits upon Reason's back." - Poor Richard's Almanac
  14. Re:So could... by digitalunity · · Score: 2, Insightful

    Not really. There is no real escape from national laws with respect to the internet. The reason is simple - everyone is connected! Google has a physical presence in the US, so the company can be penalized in the US for actions of the company abroad.

    Hypothetically, say you have a ship in the middle of the ocean. You, nor your company have no physical presence anywhere other than the ship. You still need peering from someone on the internet. Whether that be joe blow or AT&T, you need peering. So you decide to host the pirate bay on your ship. RIAA sues your peering provider to terminate your internet access. Your peering provider is in the US. Your peering provider loses the copyright battle(assuming, in this fairy tale land they actually fought it) and shuts off your internet access. Ok, that's fine and good, you can just move the ship and find another peering provider. Repeat ad nauseum. Eventaully, you run out of people willing to peer with you.

    You need to get peering from someone with sufficient political clout that THEIR peering provider isn't willing to cut them off, AND is willing to stand up to international pressure to terminate your access. I think there's a reason a lot of nefarious activity on the internet comes from Russia. Nobody has the clout to take russia offline and russia doesn't mind having all the crooks using their tubes.

    --
    You can't legislate goodness. Let each to his own destiny, by will of his freely made choices.
  15. Re:Wait, back that up, reverse it. by RobVB · · Score: 2, Insightful

    The heat certainly doesn't disappear, but you're just pumping heat into cold water with this system. The transfer of heat from a warm to a cold substance is a process which increases entropy, which means it's a spontaneous process (it doesn't take any energy to do it).

    Air-conditioning, on the other hand, transfers heat from a cold to a warm substance (the cooled air inside becomes cooler, the warm air outside becomes warmer), which is not a spontaneous process, meaning you're using extra energy. This extra energy is ultimately wasted as extra heat in the warm substance.

    Also, the extra energy which A/C uses generally comes from burning fossil fuels at relatively low efficiencies, emitting even more heat into the atmosphere.

    All in all, you're putting a LOT less energy (heat) into the earth if you're using a spontaneous process to cool your stuff.

    --
    I'd rather you rationally disagree than irrationally agree.
  16. Dealing with growth by supernes · · Score: 4, Funny

    Can't you just heat it up to sterilize it?

  17. not a thermal insulator and heat tax by goombah99 · · Score: 5, Insightful

    Other than a set up for your gag, I don't see why you call paint a thermal insulator. It does not have to be so. many kinds of coating promote thermal coupling.

    One thing that does bother me is dumping waste heat in someone elses backyard for free promotes the inefficient use of energy. that is, I can decrease my cooling costs by using more efficient but more expensive computers which incidentally produce less waste heat, or I could use less expensive inefficient computers and take advantage of public domain cooling, like cayuga lake.

    Is Cornell paying a tax to use Cayuga lake as a heat dump? that would help internalize the economic externalities that drive them to consume more electricity because the cooling is free.

    likewise for sea water cooling.

    This might seem like worry much about a small thing: isn't the cooling resevoir comparatively infinite? the answer is surprising no, not only is it not infinite, it's never going to grow, and we have already saturated it in much or the US and Europe. For example the big limit on Nuclear power plant growth is now availability of cooling. SOme rivers in Tenesee are known to heat up to 80 degrees when the power plants operate a full power in summer.

    thus this needs to be publicly regulated now.

    --
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    1. Re:not a thermal insulator and heat tax by afidel · · Score: 3, Insightful

      Not sure of the specifics of Cayuga lake but if it's anything like the Great Lakes then there is a large area of cold water that is basically devoid of life. One recent plant used the incoming city water supply which is drawn from a cold deep region as a thermal sink, since the water was just going to heat to ground temperature anyways the net effect was slightly lower heat load on the earth surrounding the cities water pipes. Of course the energy sink potential isn't infinite, but it's potentially very large and if it reduces the one side of the energy equation by ~80% then that's all the fewer resources we have to use up. Pardon me if you take offense but you sound a bit like the people in the Greenpeace movement who can't see the forest for the trees, we need to take advantage of things like freecooling and nuclear power so we can reduce the immediate resource usage that is occurring. If we find better ways to do things down the road that's great going for cleaner (not clean) options today is better than waiting decades for something perfect to come about if ever. We aren't going back to hunter gatherers so we need to do what we can we the technology we have to minimize our impact.

      --
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    2. Re:not a thermal insulator and heat tax by drenehtsral · · Score: 2, Informative

      Cayuga Lake is hard to talk about as just one ecosystem, because it has such a strange set of features... It is (like all of the Finger Lakes) a collection of water in the bottom of a glacial valley. Unlike many such lakes, however, Cayuga lake is VERY deep in places (over 400 feet deep), and there are (if I recall correctly) springs or caves or something like that at the bottom in the really deep parts. That being said, it also has a decent sized shallow shelf, and a bunch of small bays and swamps where various creeks discharge. It's the shelf-like area at the south end where the cooling intake and outlet pipes are.

      Much of the difficulty assessing whether the heat being pumped into the lake was going to have any negative impact or not had to do with the constant protesting by massive numbers of hysterical but scientifically illiterate hippies (if you've lived in Ithaca for a decade or more, you know who I am talking about). As sad as it is, because anything Cornell released or published was decried as bunk if it didn't damn the project, it didn't seem to matter any more what (if any) case they made to the community as a whole, so there wasn't much effort after some point to communicate anything clearly about this project. I don't blame them, it must have been like trying to piss out the sun getting those damn hippies to shut up long enough to have any sort of rational discussion.

      In any case, I doubt it has done nearly the harm that the late '70s and early '80s did when the city essentially pumped any excess sewage right into the lake with minimal if any treatment. In any case, I think a heat tax would be a good idea, but only if it were absolutely universally applied (Apply it to residential, commercial, public sector, and industrial waste-heat and in some sort of a meaningful and constant form (X cents per Y million Joules)).

      --

      ---
      Play Six Pack Man. I
    3. Re:not a thermal insulator and heat tax by volxdragon · · Score: 2, Informative

      Oh god no, not another tax in Ithaca....I remember having to buy tax stickers that you applied to EACH trash bag you put out at the curb (and you had BETTER make sure there were absolutely zero recyclables in the bag or the trash people would shred the sticker and the bag leaving trash everywhere on your front lawn for you to deal with). Talk about a PITA...

      But you're right, the hippies up there make even the most left-wing liberals look centrist...

  18. there are multiple ways to sanitize water... by way2trivial · · Score: 2, Interesting

    You can keep pool water sterile/inhospitable with other methods

    o3 as used in pools should be ideal here- it disappears from the system very quickly.

    chlorine (bleach) does tend to sit around in the water and react longer, o3 is very toxic to life, but tends to obliviate itself

    a giant corona discharge wire on the inlet-- no?

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