3M Innovation: Immersion Cooling using 3M™ Novec™ Engineered Fluids
3M is developing a simple, passive, 2-phase (evaporative) cooling technique that involves immersing servers in a bath of 3M™ Novec™ engineered fluids, non-electrically conductive fluids. This method has the potential to decrease power usage compared to traditional air-cooling methods, reduces the need for most air cooling infrastruture and liquid cooling pumps, and provides inherent fire protection for servers.
Computer boards, chips, UPS systems and other electronic components give off a tremendous amount of heat, which must be removed in order to ensure their reliable operation.
Air cooling (typically employing chilled water to cool the air entering a rack of servers) is the predominant method for cooling server racks. However, chillers consume a considerable amount of power. So does the air handling equipment that moves air around the datacenter, and the fans that draw cooled air through the servers. In fact, the EPA and industry groups such as ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers) have concluded that conventional air cooling technology is a leading cause of inefficiency, often consuming the majority of a data center's electricity.
To overcome these problems, 3M is developing a simple, passive, 2-phase (evaporative) cooling technique that involves immersing servers in a bath of a non-electrically conductive fluid, such as 3M™ Novec™ engineered fluids. These fluids are a nonflammable, low-toxicity material with a global warming potential of one (about the same as naturally-occurring carbon dioxide).
Passive 2-phase immersion cooling has been used for decades to cool high value electronics such as supercomputers, transformers and traction inverters. This technology is favored for its simplicity, reliability, power density and performance.
What's new about the 3M concept for data center cooling is the use of semi-open baths in place of hermetic enclosures. Novec 649 fluid removes heat through direct contact with the heating elements, which raises the 3M fluid to its boiling point. The vapor that is generated rises and is condensed through outside air or normal facility water. No energy is required to move the vapor, which naturally rises and then falls back to the bin in its liquid state. A chiller is not necessary.
Passive 2-phase cooling can significantly decrease power required to cool servers compared to traditional air cooling methods. It simplifies facility construction by reducing floor space requirements, eliminating the need for air cooling infrastructure such as plena, air economizers, elevated ceilings etc. The 3M technique also eliminates the need for connectors, plumbing, pumps and cold plates associated with conventional liquid cooling.