Slashdot Mirror
Google's Chiller-Less Data Center
1sockchuck writes "Google has begun operating a data center in Belgium that has no chillers to support its cooling systems, which will improve energy efficiency but make weather forecasting a larger factor in its network management. With power use climbing, many data centers are using free cooling to reduce their reliance on power-hungry chillers. By foregoing chillers entirely, Google will need to reroute workloads if the weather in Belgium gets too warm. The facility also has its own water treatment plant so it doesn't need to use potable water from a local utility."
If it wasn't for the required internet connectivity google could go off the grid completely. But they already own so much fibre and the public internet seems to need google more than they need it.
Soon they will generate all their own power from wind and solar, convert all their employees shit to power so they don't need the sewerage system either, send all their traffic through the network of low earth orbit satellites they are about to launch which also conveniently beam solar power back down to them.
So basically at the end of the day they will be able to buy or swindle a plot of land from some country with low tax, bring in all their own employees, contribute absolutely nothing to the local economy and leave when the sun goes down. It's great really, saves them on lawyers that would otherwise help them pussyfoot through the swaths of modern over-regulation and the satellites will help them get past any censorship / connectivity problems.
And if China start shooting down their satellites, Google will make satellites that shoot back
well, it might be unreliable, but i think you're overestimating the reliability of normal data centers. even if failure is twice as likely at this data center than others, i think it still improves overall performance and reliability enough that it's worth building. or at least google seems to think so.
weinersmith
Remember that even on hot days not all of the traffic through the datacenter needs to be rerouted, and I'd imagine that a location selected for a datacenter like this was chosen for the infrequency of days that will require rerouting. Do you know how much it costs to cool a datacenter, and how much this will save? I don't, but Google probably does, and they probably wouldn't make a decision to do something like this without comparing the savings with the potential cost from decreased lifespan of computers running hot and losses due to downtime. I would also imagine that Google will be working to greatly increase stability during rerouting, given the comments from the end of TFA about other power saving uses, such as routing traffic to datacenters where it's night, meaning "free cooling" can be used since it's colder outside, and off-peak electricity rates are in effect.
I think the concept is interesting, and it makes me wonder if we'll see more datacenters built in areas of the world more conducive to projects like this in the future.
If you have chilled water, you have a chiller, which means you have compressors. Process water or ground source water usually is not cold enough to be an effective cooling medium. You want a high delta T between the entering air temp and the entering water temp to induce heat transfer. Closed loop ground source water is extremely (prohibitively) expensive and open loop is quite a maintenance hassle due to water treatment. High efficiency chillers paired with evaporative cooled water towers with economizer capability is very efficient and reliable. Usually you can get down to around 0.5kW per ton with high efficiency chillers at full load and with multiple staged compressors you can do even better with part load conditions. The cooling towers are usually pretty low with around 0.05 to 0.15kW per ton. Use VFD's on the secondary pumps and cooling tower fans, and you can get cooling in at 0.75kW per ton for the whole plant at peak and even lower and part load conditions (95% of the time).
I just designed a data center for a large Big Ten univeristy and there were no large air handlers involved at all. The system had two 400-ton chillers with the chilled water piped directly to rack mount APC fan coils. Without "green" being the basis of design, the chiller system still operates right at about 1kW/ton.
I'm not not licking toads.
You do not need a chiller to operate a datacenter in many environments at all. Based on the 2nd edition of ASHRAE's Thermal Guidelines for Data Processing Environments (which was developed with direct input from the major server providers), you can run a datacenter at up to 90F. Seriously, 90F into the rack. When it comes out the back of the rack, you collect the heat exhaust at 100-110F. "Chilled" water at 81F is more than enough to knock that 110F down to 90F- ready to go back into the front of the rack.
The 81F water can be produced directly from open cooling towers (direct evaporation) whenever the wetbulb is lower than 76F (4 degree approach plus a 1F on your flat plate that isolates the datacenter loop from the open tower loop).
You designed an efficient datacenter, but you're five years behind cutting edge (not actually a bad thing for most critical environment clients). The next wave of datacenters will have PUEs of 1.2 or less and redefine the space from a noisy but cool space to hang out to a hot machine room with industrial heat exhaust design.
I actually just finished a chiller less 8MW schematic design and analysis for a bid. It was my second this month (the first was a cake walk - an extreme Twb of 67F, the second was west coast light conditions).
PS: Secondary pumps? Seriously? Unless you have to boost up to 25 psi to feed a Cray or some other HPC I thought everyone who cared had moved onto variable primary-only pumping. (Sorry, feeling a bit snarky after hitting a 40 hour week on Weds...)