Intel has reported positive results from a year-long test of a novel system that cools servers by immersing them in mineral oil. A cooling power usage effectiveness (PUE) figure of 1.02 to 1.03 was measured with no impact on the performance of the seven dual-socket Xeon servers. This means that the oil vats needed only two to three percent more energy than the servers themselves. By contrast, a typical data centre has a cooling PUE as high as 1.6, meaning that non-IT equipment in the data centre boosts total power usage by 60% of the power consumed by the servers.
To combat this extra power consumption, some companies such as Facebook have built data centres in areas where the ambient air can be used to cool the servers, eliminating the need for air conditioning equipment. Oil immersion is a potential alternative for situations where ambient air cooling is not possible.
Intel is currently looking at several other advanced cooling technologies, including a proposal to study immersion cooling with a two-phase fluid that transfers heat by boiling off and condensing. The company does not have any immediate plans for making servers specifically designed for oil immersion cooling, but they are examining the tradeoffs involved in building an oil-optimised platform.