The warmer weather during the spring and summer is, of course, a welcome thing, but not necessarily for data centers. The heat and humidity can spell trouble for facilities that aren't equipped to handle the temperature fluctuations during the warmer months. In this interview, Steven Harris, the director of data center planning for the Forsythe Solutions Group, a data center consultancy, offers advice on how to prevent a data center from becoming a broiler.
How should facility managers plan for the upcoming temperature changes?
Steven Harris: The first thing I would tell you is if your data center is in a well-designed, well-built, well-insulated building, you will be somewhat insulated from the huge temperature fluctuations that can occur in the June-July-August time period. But that's not always the case for older data centers.
So what should older data centers do first?
Harris: The best thing you can do is try to protect -- try to shade -- the building equipment. These are air-cooled data center environments, similar to the technology you have in your house. In an air-cooled environment, you have heat ejection units outside, maybe on the roof. Shading that can help the air-conditioning system run cooler.
If you do have your chiller units outside, especially in the southern parts of the country, you can shade those too. Anything you can do to drop the ambient air temperature will help from an efficiency standpoint.
What about the data center facility itself?
So you basically want to create a second wall?
Harris: If you look at a typical wall, about one-third of the way up is drywall, and then there are windows the rest of the way. I would install studs, plywood and drywall from the floor to the ceiling. So you've created this air gap, same as double-pane-insulated windows.
I've heard that there are things you can do on the building's roof to save energy.
Harris: We see a lot of older data centers that potentially have this issue, especially if the data center's ceiling is the building's roof. We see a lot of older buildings where, if you have a flat roof, in the old days they tarred them black. That absorbs heat. In the winter, it might be a good thing, but in the summer it's bad. Re-roofing a building can be fairly expensive, but the next time it has to be done, don't go black. Go white.
What about installing a so-called green roof with soil and plants?
Harris: The building has to be designed and built to handle that load. By planting grass or trees, you could potentially put a huge load up there. Also, dry dirt is one thing, while wet dirt is another. Aside from the weight, you have to figure out where the water is going to go, that drainage needs to be designed in. It's one of these things where it's a neat idea, but it's almost always something that has to be done in a newer structure. It's kind of like putting a swimming pool on the roof without planning for it.
Is there anything else data center managers should plan for?
Harris: You have to make sure your air-conditioning system is maintained. I think a proactive program would have, at a minimum, your CRAC [computer air conditioning room] units being looked at regularly, and it may be something as simple as making sure your filters are clean. Filters are white when clean and gray when a little dirty. I've seen some that are black. It's not good for efficiency and it reduces your ability to cool the data center.
You also want to make sure you have some redundancy. If you need 50 tons of air conditioning and all you have is 50 tons, you don't have extra capacity to throw at the problem. If the heat load does increase, you'll want a little bit of backup to help on those very hot days.