Cray has been a leader in power and cooling technologies, including liquid cooling, since the Cray-1 supercomputer in 1976. The new ECOphlex technology promotes energy savings by enabling greater system density, reducing the need for expensive air cooling and air conditioners, and limiting the need for chilled water.

"IDC research shows that power and cooling efficiency, and system density, are among the top concerns of high performance computing (HPC) buyers today. Escalating system sizes and sharply rising energy costs are contributing to these concerns", stated Earl Joseph, IDC program vice president for HPC. "ECOphlex technology is designed to alleviate these issues for high-end HPC users and could be an important differentiator for Cray as they prepare to enter the petascale computing era."

"Most large computers today exhaust heat into the air, and then the Computer Room Air Conditioner (CRAC) units have to remove the heat from the air and put it into chilled water. This method is very inefficient. For a petascale system, the area taken up by the CRAC units could exceed the computer footprint, wasting precious data centre space and energy", stated Cray Chief Technology Officer Steve Scott.

"Other systems use chilled water coils embedded in each computer cabinet and sometimes even embedded invasively into the compute blades. With ECOphlex technology, you still use chilled water, but much less of it. And because of our unique engineering, you don't need to worry about water condensation or leakage that could harm electronic components. The combination of our ECOphlex technology, unprecedented upgradeability and environmentally-friendly design philosophy, makes Cray systems the industry-leading 'green' solution."

The ECOphlex technology is designed to be "room air neutral", meaning that the temperature of the air entering the system is roughly the same as the temperature of the air exiting the system. In a recent test at a government site, ECOphlex technology removed 100% of the heat.

Cray's new high-efficiency cabinet with ECOphlex technology has the flexibility to use either the company's high-efficiency vertical air cooling or the new liquid evaporative phase-change cooling technology that converts an inert coolant, R134a, from a liquid to a gas. Systems with the ECOphlex technology also have the flexibility to use chilled or unchilled water at various temperatures, reducing the need for many CRAC units. The technology's phase change coil is more than 10 times as efficient at removing heat from the compute cabinets as a water coil of similar size.

According to Steve Scott, "Attempts to improve energy efficiency often involve lower-power processors or reducing the frequencies of standard processors. But this requires more processors to achieve a given performance level, which reduces performance efficiency. And since many application codes have limited scalability, this strategy can reduce an HPC system's breadth-of-applicability, making it a more limited-purpose machine. ECOphlex technology allows HPC sites, large or small, to enter the multi-petaflops era, tackle the most daunting science and engineering problems, and apply large numbers of high-performance processors at industry-leading densities while achieving strong energy efficiencies on a broad spectrum of applications."