Computers dissipate a lot of waste heat. You don't notice it in a single desktop system but put 48 high-performance servers on top of each other in a rack and you have some serious cooling problems. Not just the electronics, a high-performance hard disk drive also kicks out a lot of heat.
I used to work for MSFT and one lab I managed had over 1,000 computers. The cooling system was very specialized and when it went down (a certain 'S' company), the temperature in the lab would go from shirtsleeve to over 100�F in 30 minutes.
Facebook is thinking outside of the box with their new datacenter -- from Slashdot:
Facebook Saves Datacenter Costs with Frigid Arctic WindTalk about win/win. Beats having to deal with clouds and rainstorms in your server rooms. The facility is three buildings, each 300,000 sq. ft. - that would be a single square floor 1,732 feet on each side -- big building. 6.9 Acres if you are a farmer...
One year and seven months after beginning construction, Facebook has brought its first datacenter on foreign soil online.
That soil is in Lulea, town of 75,000 people on northern Sweden�s east coast, just miles south of the boundary separating the Arctic Circle from the somewhat-less-frigid land below it.
Lulea (also nicknamed The Node Pole for the number of datacenters in the area) is in the coldest area of Sweden and shares the same latitude as Fairbanks, Alaska, according to a local booster site.
The constant, biting wind may have stunted the growth of Lulea�s tourism industry, but it has proven a big factor in luring big IT facilities into the area. Datacenters in Lulea are just as difficult to power and cool as any other concentrated mass of IT equipment, but their owners can slash the cost of cooling all those servers and storage units simply by opening a window: the temperature in Lulea hasn�t stayed at or above 86 degrees Fahrenheit for 24 hours since 1961 (PDF), and the average temperature is a bracing 29.6 Fahrenheit.
Air cooling might prove a partial substitute for powered environmental control, but Facebook�s datacenter still needed 120megawatts of steady power to keep the social servers humming. Sweden has among the lowest electricity costs in Europe, and the Lulea area reportedly has among the lowest power costs in Sweden. Low electricity prices are at least partly due to the area�s proximity to the powerful Lulea River and the line of hydroelectric dams that draw power from it.
�We are proud to say that this is likely to be one of the most efficient and sustainable data centers in the world,� according to the blog item/Facebook page update about the center going live. �All the equipment inside is powered by locally generated hydro-electric energy. Not only is it 100% renewable, but the supply is also so reliable that we have been able to reduce the number of backup generators required at the site by more than 70 percent.�
