In an effort to cut down on computer server system-based electricity bills and carbon emissions Timothy Shedd, an associate professor of mechanical engineering at University of Wisconsin-Madison, has developed a computer cooling system that claims to be 10 times more efficient than the air conditioning that are currently used in the university’s server rooms. The invention is now at a stage where it can be spun-off and commercialised.

Cooling costs at server farms are racking up annual bills nearing $2bn, or close to 10 per cent of the capital cost, and just three companies make and install most of the big cooling systems, according to Timothy Shedd, an associate professor of mechanical engineering at UW-Madison. Shedd has spent more than a decade studying and designing computer cooling systems.

“Cooling can make up 50 percent of the annual operating cost, so the cost of cooling can quickly become larger than the capital cost of the computers themselves,” he said in a news report published by UW-Madison via news service Newswise.

Shedd has taken his specialised know-how to start a spinoff business called Ebullient to commercialise his invention. In Shedd’s system a pair of translucent plastic tubes filled with air conditioning refrigerant enter each computer case whereby removing the heat from the computer and then exiting the liquid outside the casing once it passes through.

Firstly, a plastic chamber attached to the processor absorbs heat at the point of creation. Secondly, a network of tubes and a pump carry the heat to the roof, where it is sent out into the atmosphere.

While still using the refrigerant, his system eliminates three parts of a normal computer cooling system, the compressor, condenser and evaporator.  According to a report published on the University’s site, the system is 10 times more efficient than the air conditioning that dominates the server field.

Some competing ideas have used water-based systems, but that can carry a lot of risk to a computer’s integrity, according to Shedd. Therefore, he chose a refrigerant that would not damage the computer if it spills. While the refrigerant carries less heat than water, he has had to ensure that his system allows the fluid to boil in the chamber atop the chip and condense back to liquid on the rooftop heat disperser. The phase then ramps up the heat transfer rate without threatening the processor, explained the University’s news report of the spin-off.

Shedd estimates that his system can cut cooling costs by up to 90 percent, but he also understands that his device has to prove itself before getting to the commercialisation stage. The devices have  been working for five months non-stop at a group of servers at the UW-Madison College of Engineering. This will help provide proven use of the product before pitching the product to target customers, such Amazon, Google and other data centres.

Data centres are growing seven to 10 percent a year in the United States, with the biggest growth in the Midwest, Shedd says.

The invention is covered by patents Shedd assigned to the Wisconsin Alumni Research Foundation.

 

Picture: Timothy Shedd, (pictured) examines a computer equipped with his novel cooling system. Tubes circulate refrigerating fluid through a special heat exchanger (under the X-shaped structure) on the processor that is the biggest heat source in a computer. Source: David Tenenbaum/University of Wisconsin-Madison.