Does Geothermal Cooling Make Sense for your Datacenter?

Does Geothermal Cooling Make Sense for your Datacenter?

Summary: It's cold down in the basement. Why don't we keep our servers there?


With TierPoint's announcement of funding for their new datacenter they also included the tidbit that they plan to use geothermal cooling as a low-impact, high-efficiency method for providing temperature control in the datacenter rather than traditional chiller cooling. Their planned system is non-consumptive, which means in addition to using the temperature gradient to provide "free" cooling it also reduces the environmental footprint of the datacenter by not introducing pollutants into the local water system that would normally need to be dealt with by sewage treatment plants, making the installation that much more green.

By taking advantage of the natural cooling available underground (the mean temperature 5 feet underground is between 50 and 60 degrees Fahrenheit) a high-volume, closed loop system should be able to deliver significant cooling to a datacenter built just about anywhere in the temperate climate zone. While there would be additional advantages in cooler climes, issues such as permafrost and the practicality of lower outside air temperatures during most of the year would make the investment in geothermal strictly for cooling a much iffier one.

The geothermal cooling technology is not one that I've heard brought up too often. It will be interesting to see, with the rapid growth in new datacenter construction, if a vendor market grows to fill this niche.  I made a few phone calls to people I know in the development process for new datacenters, and when I asked about plans related to geothermal, they were uniformly of the opinion that it was a power generation technology or mentioned something I had previously written in regard to datacenters in Iceland.

It will be interesting to see if a greater awareness of the possibilities of making use of the temperature gradient, even in places where no one is really aware of it. We are too many generations away from the "root cellar" in the minds of most IT people; practical methodologies for stable temperatures and cooling that were developed a long time ago rarely enter the thought processes of the technologically driven IT professional..

Topics: Hardware, Data Centers, Storage, Telcos

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  • Always wondered

    why they keep the doors closed in the winter - while running the A/C. Want to save some energy?
    Roger Ramjet
  • RE: Does Geothermal Cooling Make Sense for your Datacenter?

    I think you're being a little pessimistic about the IT mindset. Let me brighten your day :D

    We're building a new 'Library' on our college campus and its climate will be geothermally regulated - including, partially, our new campus core switch room. Its not the data center, but it will house all of our Voip equipment and main campus routers, etc. We carefully considered the options and may need to augment with traditional cooling. We're still planning so we'll see - but geothermal was at the top of our list.
  • Totally impractical

    Yeah, the temperature in your basement is 50 degrees. Until your equipment has warmed it up. So unless you plan on digging a vast network of pipes through the ground with a heat exchange fluid and pumps to pump it through the ground, you haven't gained anything. And of course, heat in the ground dissipates much more slowly than in the air, so you need that much more piping and fluid and pumping and electricity.<br><br>I suspect if someone runs the math, they'll find that this, like most green initiatives, is driven by imposed guilt and not practicality.
    • RE: Does Geothermal Cooling Make Sense for your Datacenter?

      @frgough Sense when does a gas transfer heat faster/better than a liquid or solid? While it may be true that geothermal cooling won't work as well as they claim, assertions of fact that are not true don't support your assessment.
      • I didn't say transfer, I said dissipate

        and gasses are much better at dissipating heat than liquids or solids because a gas can expand and leave the area, taking the heat with it, to be replaced by cooler ambient air.

        The atmosphere, composed of gasses that can quickly dissipate heat via convection is much more efficient than a liquid or solid.
    • RE: Does Geothermal Cooling Make Sense for your Datacenter?

      @frgough You need to understand geothermal cooling systems before you make ridiculous statements.

      I have built data centers and also and geothermal certified. Geothermal technology is well suited to data centers. The cost per sq ft of data centers, the power requirements, and the ability to maximize the equipment capacity per sq ft are critical metrics. The cost savings are there.
      As far as the technology, geothermal systems are 50% more efficient (on average) for cooling. Less moving parts (more reliable), quieter, and use less space. It is a matter of science; The heat is transferred in a wet environment at 52F (depends on latitude) instead of whatever outside air is available. Liquid transfer much more efficient. Dissipation is engineered into the configuration. That said, all geothermal systems are not created equal and each project needs to be evaluated based on location, size, growth potential.
  • Seconded

  • Works if the location is right

    Geothermal works great, but location is important. With geothermal you're usually installing coils deep enough underground that you're in the groundwater. The groundwater needs to be moving quickly enough to dissipate the heat/cold, or you'll just warm/cool the region around the coils/radiator and lose the effect.

    This website has a strong right-wing political presence that is extremely distracting from what I assume is your primary function, IT news. I expect to have my intelligence challenged here with news and descriptions of new technology, not insulted by viewing some dittohead regurgitating tired demagoguery.
  • RE: Does Geothermal Cooling Make Sense for your Datacenter?

    Here in Toronto Ontario they have been doing this for a few years now. Below about 100 ft Lake Ontario remains a constant 41F or 4C year round, the point at which water is most dense. Big pipe runout into the lake to collect the water at 230 ft. Hence the name Deep Water Cooling. Circulated around a number of office towers for A/C usage. True the catch is location, only a few big cities on the shore of a Great Lake. What is done with the warmed lake water I dont know. I assume it could just be dumped into the city storm sewers and return to the lake.
  • RE: Does Geothermal Cooling Make Sense for your Datacenter?

    In Germany they have whole communities which have the temperature regulated, summer and winter by this means. It is very efficient as you do not have to dig very deep to reach a level where the temperature is steady year round.

    Once you lay a large diameter pipe over a reasonable length, at the right depth, a large fan will circulate cooled air in the summer and warmer air in the winter. Clearly, in cold climates, you need supplementary heating. But, overall energy costs are significantly reduced as most of the work is done for the cost of running the fan. The capital costs are higher, obviously.
  • Great Solution

    For many locations is a great solution. I use DX technology which is good for most locations. No water supply (underground or lake) needed. Highly efficient, highly reliable, small footprint. The savings come by reducing KWs for cooling. Depending a few factors, you can expect about 15% reduction in overall electric. Assume 30% overhead for traditions AC and 5% more for UPS support of AC in your capacity plan. Cut that in half for geothermal. about 1.15KW per KW of equipment versus 1.35KW per KW of equipment. Save on electric bill, maintenance, and also adds "capacity" to your capital investment of data center space.
  • RE: Does Geothermal Cooling Make Sense for your Datacenter?

    At Prairie Bunkers Data Center Park in Nebraska, where the in-ground temperature is about 55 degrees, our drilling contractor Leuck's Drilling and Great Plains Data Center Builders have designed an in-ground, closed-loop, "geothermal" cooling system which is estimated to reduce cooling costs by 50% in our DataBunkers. Such systmes are in broad use throughout the Midwest, in Canada, Sweden and Germany, where they are known as "bore-hole" systems. Geothermal cooling will become a standard technology to reduce operating costs, as well as to increase the "sustainability" and PUE ratings, of data centers.

    Gary Hultquist, Chairman
    Prairie Bunkers, LLC