Even the most efficient air-cooled data centres waste 20 percent of their power running fans inside the servers, according to British liquid-cooling specialist Iceotope, which launched its water-cooled servers at the Cebit trade show.
The first modules compatible with Iceotope's cooling system each contain two of Intel's new six-core Romley E5-2600 processors. A rack can hold 48 of them, the company said. The modules are loaded from the front and back of the rack, which does not need the hot aisle/cold aisle arrangement common in air-cooled data centres.
While some server manufacturers take a half-hearted approach to liquid cooling, pumping fluid through the heatsinks on top of key components such as processors, Iceotope goes all-in, immersing half-size SSI (Server System Infrastructure) motherboards in Novec, an inert cooling fluid developed by 3M, and sealing them inside special modules. The cooling fluid carries the heat away from the motherboard through convection before giving it up to a heat exchanger through which water is pumped at low pressure, according to Iceotope CTO Peter Hopton.
Iceotope can cool an entire 20kW rack with a pump consuming just 70W, whereas some air-cooled servers contain fans rated at 200W or more per shelf, Hopton said. The Iceotope system warms the water by just 5 degrees Celsius, and can operate with incoming water temperatures of up to 45C, which means year-round free-air cooling is possible almost anywhere on the planet, he said.
A cabinet will cost just under £20,000, including two heat exchangers, two water pumps, two power supply units and all the necessary chassis. The first processor modules, each containing two of Intel's new six-core Romley E5-2600 processors, 64Gbytes of RAM and SSD storage, start at £3,995.
The boards in the first modules come from Supermicro, and Iceotope will sell the modules through some of Supermicro's channel partners, Hopton said.
Iceotope prices its modules at 20 percent above equivalent air-cooled equipment. "We like that number because it's known that lifetime power costs are greater than capital equipment costs, and we save 20 you percent of the cooling cost," he said.
While Iceotope's servers aren't the cheapest around, Vik Malyala of Supermicro sees a market for them among the cost-conscious. "This is for people trying to bring the overall cost of operating a data centre down," he said.
Hopton hinted that data centre cooling could even become a profit centre rather than a cost centre: The waste heat in the cooling water could be reclaimed, using a heat pump to concentrate it for use in district heating systems in offices or housing near the data centre.