Article on Slashdot: Using the Sea To Cool Your Data Center
"We haven't yet seen signs of the Google Navy of seagoing data centers that use the ocean for power and cooling. But data center developers are planning to use sea water air conditioning in a new project on the island nation of Mauritius in the Indian Ocean. Cold water from deep-sea currents would be piped ashore to be used in a heat exchanger for the data center facility. A similar system has been used to replace the chillers at Cornell University, which draws cold water from Lake Cayuga. The Cornell system cost $50 million, but has slashed cooling-related energy usage by 86 percent."
Sea water has several disadvantages mostly keeping the system clean, barnacles, muscles and other small plants and animals will get sucked in to the system, and eventually clog up everything. It's also very corrosive. In addition hot water discharged from the system will hurt local ecosystems in both salt and freshwater systems.
Using the Hull of a ship would solve the clogging problems, where there is a large mass of metal in which to dissipate heat without having to pump seawater.
Still using seawater is still not a very good solution. Even is it's cost effective in reducing energy consumption.
When I had my start-up Nisvara Inc.(2002 to 2006 RIP) we worked out that we could accomplish the same using nothing but chiller towers that just used evaporative cooling. In cooler climates like where we were based at NASA Ames Research Center in Mountain View Ca, we worked out that we could cool the largest computer cluster what would have been built at that time using nothing just large truck style radiators and fans. No compressors or any active cooling just circulating water or cooling fluid.
A lot of data centers objected to the use of water because it would damage equipment. The Nisvara solution kept water in continuous copper tubes without any joints or seals. Still that wasn't enough to belay their fears of water contacting electricity, so we also found other suitable coolants such as using 3M Novec 1230 Fire Protection Fluid. It's amazing stuff. Totally green and safe also known as "Dry Water" and "Waterless Water", will not harm equipment and just happened that it could be used as a coolant too.
It may even be useful as a refrigerant because it can phase change at a lower temperature then water, but this would have required more research.
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