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Intel Shows Data Centers Can Get By (Mostly) With Little AC
Ted Samson IW writes "InfoWorld reports on an experiment in air economization, aka 'free cooling,' conducted by Intel. For 10 months, the chipmaker had 500 production servers, working at 90 percent utilization, cooled almost exclusively by outside air at a facility in New Mexico. Only when the temperature exceeded 90 degrees Fahrenheit did they crank on some artificial air conditioning. Intel did very little to address air-born contaminants and dust, and nothing at all to deal with fluctuating humidity. The result: a slightly higher failure rate — around 0.6 percent more — among the air-cooled servers compared to those in the company's main datacenter — and a potential savings of $2.87 million per year in a 10MW datacenter using free cooling over traditional cooling."
I do wonder how things could be improved with a decently sized stack... the higher an exit chimney, the more draw you'll get from the temperature differential. If your computer rooms are near the base of a decent sized office building, and you have a 20 story stack, I'd expect you could get away without any intake or exhaust fans.
Anyone here that can confirm or deny this?
I asked the president of an engineering firm that I work for about this. He ships racks of boxes, each holding DSP boards on backplanes, each backplane has it's own PSU.
When I asked him why he doesn't just have one or two -big- power supplies in the unit, he said that he tried that, but the cost of the non-standard PSU was higher than all the ATX PSUs put together, and then some, and replacing the units when they eventually fail would be tricky, as opposed to just stocking more ATX PSUs.
I agree that it's a good idea, but until there's enough volume of large multi-output PSUs shipping, the cost of manufacture makes the product unworkable (unless you think big-picture and want to spend more up front for power savings over the whole unit's life).
Generally, the people who use the hardware aren't the ones building it, and buyers usually go for the lowest bid.
"Sometimes, I think Trent just needs a cup of hot chocolate and a blankie." -Tori Amos on Nine Inch Nails
The standard replacement cycle is about three years, so until they try that, this doesn't mean a lot. Also, what was the density of the data center? I still love the story of a datacenter with some DSLAMs that cooled left to right which were put next to each other in about 12 racks and the rightmost one caught fire once a week...
Also, I don't know the climate there, but in the regular climate here where it goes between -10 and +35 celsius (that's between 14 and 95 fahrenheit) and there's a good dose of humidity, the failure rate might be somewhat bigger...
I set up a datacenter at my old job in Alberta, and that's exactly what we did.
We ran exhaust ducting to the offices, and tied intake into the building's cold-air return. From September to May fans moved colder air into the data room and hot air into the office space. June to August we ran the AC, and shut off the "winter lines" with dampers.
It worked extremely well.
Part of the problem is people are looking for very complicated solutions for very simple problems.
In retrofitting a standalone building, all you really need to do is reduce the amount of heat a building gains from the sun by improving it's R value and use sensible ducting to draw air through the building. I've seen some super energy efficient designs where each floor is vented, so that the building is itself a chimney, with cool air coming from vents from covered areas near the base, and enough size provided at the top to pull enough from the bottom, which is also easily aided by fans.
In building an entirely new datacenter, it would make sense to bury the server rooms, and cover the concrete structure with earth and solar panels. Combined with a flywheel load balancer, you could have an "off the grid" datacenter with the grid for backup. During the daylight hours, especially in the south, the panels can provide a good deal of the A/C and power necessary. At night the flywheel can continue powering the data center for a while, and turn fans without compressors to cool the equipment with night air.
This can all be done with existing technology. The trick is to convince people that green investment will lead to a return in the long run. I haven't personally looked at average rate increases in electricity, but the difference between efficient and additional construction expenses versus long term energy price fluctuations probably looks very good.
So this study is not actually useful for people who need to build data centers in more humid places then new mexico
Humidity only really matters for two reason - If too low, you get a lot of static buildup, and if too high, you get condensation.
Condensation only tends to happen on objects cooler than ambient, which doesn't really apply to running servers. Static matters a lot more, but you can raise humidity a lot cheaper than you can lower it, so, not as much of an issue there.
And as a bonus, more humid air can carry away more heat than the same volume of less humid air.
Antarctica would be kind of a neat place for a data center. You have all of the cold air you need and there is enough wind for power. Just have to find a way to keep it stable amidst moving ice.
Aluminum wiring is a FIRE hazard and was BANNED in all new
houses in the US due to it.
You might be able to get away with it outdoors, but it is
most likely a bad idea based on the indoor results.
http://www.physicsforums.com/showpost.php?s=7d306106c574b8acd101e052ab90be42&p=615606&postcount=6
http://books.google.com/books?id=2edigWaeGPUC&pg=PA175&lpg=PA175&dq=aluminum+wiring+ban&source=web&ots=l0eE26iMkt&sig=rVIgBVl0gXGlJicEHA_qW8s4zY0&hl=en&sa=X&oi=book_result&resnum=4&ct=result
Alot of areas you cannot even get insurance for the building
with aluminum wiring in it.
http://en.wikipedia.org/wiki/Aluminum_wiring#Hazard_insurance
google "32 trillion offshore needs IRS attention"