U.S. researchers are using a simulated data center to develop new methods to reduce the heat generated by large computer equipment. Georgia Institute of Technology scientists said about a third of the electricity consumed by large data centers doesn't power computer servers, but instead must be used to cool the servers, a demand that continues to increase as computer processing power grows. The Georgia Tech scientists are using a 1,100-square-foot simulated data center to optimize cooling strategies and develop new heat transfer models. Their goal is to reduce the portion of electricity used to cool data center equipment by as much as 15 percent. "Computers convert electricity to heat as they operate," said Professor Yogendra Joshi. "As they switch on and off, transistors produce heat, and all of that heat must be ultimately transferred to the environment. If you are looking at a few computers, the heat produced is not that much. But data centers generate heat at the rate of tens of megawatts that must be removed." He said five years ago, a typical refrigerator-sized server cabinet produced about one to five kilowatts of heat. Today, high-performance computing cabinets of about the same size produce as much as 28 kilowatts, and machines now being designed will produce twice as much heat. Summaries of the research have appeared in the Journal of Electronic Packaging and International Journal of Heat and Mass Transfer.