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Keeping a Data Center Cool on the Cheap
jedimaud writes "You've heard of bubble wrap, and the boy in the bubble -- now, here's a datacenter in a bubble. I work for a government agency that, like most, is trying to cut back some costs, and one of those costs is a REAL datacenter. So, we decided to wrap the whole thing in plastic (including two 1.5 ton ACs). The room hovers about 83 degrees, however, the racks in the bubble (ok, more like a termite tent) stay about 10 degree cooler. Here's some pics to check it out."
Well, if your site is hosted by that Data Center, it just got a lot hotter in that bubble!
Linux, you magnificent bastard, I read the fucking manual!
Do not place datacenter over head. Keep out of reach of children.
... and then they built the supercollider.
"(including two 1.5 ton ACs)"
"Ton" here refers to a "ton of cooling," a measure of power. It was originally intended to mean "the power required to melt one ton of ice in 24 hours." Since that varies based on a bunch of conditions, it was pegged at 12,000 Btu/h.
When they changed the definition of "calorie" to mean 4.1868 J, converting Celsius to Fahrenheit and grams to pounds gives us a conversion factor of 1 ton of cooling being exactly 3 516.852 842 066 7 W.
In other words, each a/c unit is about 5.25 kW of cooling each, or 10.5 kW total.
Oh, and 83 degrees Fahrenheit is about 301 kelvin and a ten-degree Fahrenheit difference is a difference of 6 kelvin.
(According to my old HVAC prof, there's been little to no progress in "metricizing" the industry in the US. Having used both systems in his course, I'd say I prefer US units, if only because the unit descriptions on things like insulative properties make more sense when the units for thickness and area don't naturally cancel each other out.)
(And it could be worse. Most home a/c units are labelled on the box as putting out x number of Btu, suggesting they're disposable.)
(Well, they probably are...)
First off, a "real" data center needs a little more than 1.5 Tons of cooling; that will barely cool a single rack in a real data center.
Insulation is always a nice idea, be the fact of the matter is that to reject the heat from the space you need to provide a means of heat trasnfer. Generally, that requires a temperature differential between your heat source and the outside. If it is cooler outside than in the space, not much is required. If it is warmer, you will have to take advantage of thermodynamics and use a compressorized cycle. This can be more or less efficient, depending on the difference in inside and outside temperatures.
(A typical data center operates with a 95-110F outside design temperature, and attempts to deliver 48F chilled water to the CRAC units (Computer Room Air Conditioning). This forces about 50% of the energy consumed by the computers to be used (again) to cool the equipment.)
Call an engineer when everything melts down...
Heck, why not? Run some massive fiber along the big pipeline. Only disadvantage is that you're out on the edge of the Internet, you're not safely embedded in the middle with nice redundant capabilities.
MirrorDot is upf 7bbfed3ed64/index.html
http://mirrordot.org/stories/e90ad5cab7cfb4869cc0
1.5 ton sounds expensive, big and awe-inspiring. It's not. Most people have cheap 1 ton a/c units in their living room walls (12,000 btu). My 12,000 (1 ton) unit is barely able to cool 3 computers. Good luck with a datacenter.
keeping a datacenter cool? Thats nothing..
try moving to india to try and get your job back from dell only to get dysintry and heat stroke, lose your wallet and end up working in low grade indian miget porno to get enough money to buy a can of coke, only to get typhode.
Bubbles...pfff...
Ps. I'm writing this from Iran, send help.
I think in this case the AC only has to work on pumping the excess heat from the servers out, and not cooling the whole room. Doesn't matter how warm the room gets outside of the bubbles.
I'll never make that mistake again, reading the experts' opinions. - Feynman
and more cowbell.
Pretty Pictures!
Having recently faced a similar problem (though on a much smaller scale), we came up with almost the same solution.
As one suggestion, though, cardboard (in 4x8ft sheets) proved a lot easier to work with than plastic sheets. For starters, the plastic requires attachment at the ceiling, and will eventually come loose under its own weight; cardboard, with a single fold in the sheet, will stand upright and support its own weight for years, assuming not too high of a humidity level. For another, cardboard won't flap around and potentially block air intakes nearly so easily as plastic will.
Believe it or not, though, what we found the most effective way to make use of barely adequate AC - Don't treat the room as a closed system. You've basically used the plastic sheets to build giant chimneys - Now take advantage of that fact, and along with a high volume fan above each rack, just exhaust the air at the top outside rather than recycle it back into the room... Think of it this way... You spec your cooling to work to perhaps 110F ambient, right? At the top of a full rack, with 50-60F going in the bottom, you probably have 120-130F going out the top. Does it take more work to cool 130F, or 110F, back to 50F? Not to mention, your normal ambient shouldn't come anywhere near 110F...
the real problem with a data center in alaska is that the fucking polar bears will keep drinking all the cherry coke.
actually I am happy to see you, however that is in fact a banana in my pocket.
"(more like a termite tent)"
... The internal structure of these mounds can be quite complex, with ventilation chimneys for active temperature control" Need I say more?!
"Most termite species are tropical or subtropical, but a few live in temperate regions." I'd posit that even fewer live in a properly cooled data center. So, on the surface (no pun intended), this doesn't seem to be a good comparison.
But reading further into the Wikipedia article: "Termites have biting mouthparts and are soft-bodied, of moderate to small size. They live in dark nests and tunnels, except when the winged alates emerge to leave their parent colony." When comparing termites to geeks, they both seem to have biting mouth parts and the geeks are definitely soft-bodied. And of smaller size. And, like the termites, true geeks live in their parent's basement.
"Termites cannot themselves digest the wood that they consume." Few geeks can live on chewed-up pencils. So again, another similarity.
Lastly, Termites construct extremely large and elaborate mounds to house their colonies.
HIV Crosses Species Barrier... into Muppets
Ever wonder why computers are made of metal? Why the plastic pieces are made of plastics that meet flammability performance standards?
Tiny Tim raises his hand
Yes, Tiny Tim?
Please, Mr Deacon Sir, so that if some source of ignition is present, the computer does not turn into a fireball spewing deadly poisionous smoke, Sir!
Very Good, Tiny Tim. And what happens if someone hangs up huge sheets of generic, flammable plastic in an area with lots of potential ignition sources?
Please, Mr Deacon Sir, sooner or later it catches fire, and people die. If these boneheads are lucky, Sir, someone from the Building Facilities or the Building Inspector will see this website and make them take it down, Sir.
Very good, Tiny Tim. The rest of the class is to read up on Flammability.