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IBM Pushing Water-Cooled Servers, Meeting Resistance
judgecorp writes "IBM has said that water-cooled servers could become the norm in ten years. The company has lately been promoting wider user of the forty-year-old mainframe technology (e.g., here's a piece from April 2008), which allows faster clock speeds and higher processing power. But IBM now says water cooling is greener and more efficient, because it delivers waste heat in a form that's easier to re-use. They estimate that water can be up to 4,000 times more effective in cooling computer systems than air. However, most new data center designs tend to take the opposite approach, running warmer, and using free-air cooling to expend less energy in the first place. For instance, Dutch engineer Imtech sees no need for water cooling in its new multi-story approach which reduces piping and saves waste."
The community in which a server farms is found surely has a need for what will be thousands of gallons a day. To the benefit of all, I'd suggest diverting a small amount of the heated water (hopefully near boiling) to another piping system in the building ....
I'm sure it could be designed as a closed system with a heat exchange into the ground or outdoors. Indeed, it is the high temperature (relative to outdoors) at which the water is extracted straight off the CPU which makes this more efficient than air conditioning.
However if you wanted to let it feed into the building's hot water system, it turns out there is already a really elegant way to do that: a tempering valve. It's a mechnical device which chooses the right amount of hot and cold water (each of arbitrary, variable temperatures) to produce some fixed output temperature. So to make moderately hot water you can combine some warm water from the servers and some super hot water from the boiler. The "free" server heat offsets the amount of water that needs to be heated by conventional means.
If they meet resistance, can't they just add some salt to the water?
10 ?"Hello World" life was simple then
I worked in several banks using IBM mainframes. The server room was always like a freezer.
I think for now, many companies are perfectly ok with air cooling solutions. Besides, it's much safer to have air-conditioning and fans than some liquid flowing. The simpler the system, the less accidents occur within it...
And believe me when I say that, if a company owns an IBM mainframe, they pay big bucks and they *don't* want any accidents.
From the article: "We can use that to heat offices, or water for a swimming pool". Job Ad: "Wanted: Sysadmin, we offer: all year heated office (20+ C), swimming pool, Jacuzzi (body temperature) integrated coffe mug wamer in tabletop and always a nice, warm breeze from our datacenter." IBM could even use the swimming pool as a cooling tank (or is it the other way round?).
All IBM is saying is that water is a better heat conductor, and air is an insulator.
http://en.wikipedia.org/wiki/Specific_heat_capacity
Water ; 4 J /cm^3 K /cm^3 K
Air ; 0.001 J
Water/Air = 4000 times more heat transfer.
So, given the choice, you would use water to transfer heat.
This is why nowadays virtually all internal combustion engines of any power output use liquid cooling despite the apparent reliability benefits of air cooling. To take the transition period, WW2, as an example, you only have to look at the complexity of American rotary aircooled designs versus, say, the liquid cooled Merlin engine, to see the point. It would be astonishing if the same transition did not eventually occur for large computers.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."