Datacenter Cooling Goes Immersive

Systems that cool electronic components and machinery are moving front and center as heat waves broil Asia, Europe, and the U.S. this summer. And that's exposing a revolution in technology happening behind the scenes in hyperscaler datacenters worldwide.

The reasons are several: Rising environmental temperatures are taking traditional datacenter cooling systems offline, resulting in outages such as those recently reported in London by Google and Oracle (NYSE: ORCL).

Volume is also to blame: The larger the datacenter, the greater the need for cooling. And as components become smarter, faster, and more powerful, they consume more electricity, pushing up the energy and likewise the cooling required to keep them functional.

Legacy AC Is an Energy and Water Hog

Traditionally, air conditioning has been a favored method of cooling datacenters. We’re not talking the big blowers of the past. Instead, evaporative systems have become popular. These draw heat from datacenter facilities and exchange it for chilled water from cooling towers, which is used to power air conditioning systems. In other approaches, cooled water is delivered by coils and ducts directly to chips and chassis in datacenters.

The problem here is two-fold. First, the methods cited above can take up to half of the electricity required to power a datacenter. And they require literally tons of water.

In April 2020, for instance, Google was cited as a water hog in an investigation by Bloomberg, which reported that Google requires millions of gallons of water annually to power the cooling-tower systems at its datacenters. Allegedly, Google has sometimes demanded the water from local utilities as a condition of building datacenters in a given area.

Pulling Datacenter Cooling Out of the Water

Enter immersion cooling, a relatively recent innovation in which servers are immersed in racks containing non-conductive, or dielectric, liquids, such as certain mineral oils. Unlike water, these liquids can’t conduct electricity, so submerged servers can operate without interference. Heat from the rack is absorbed by the dielectric liquid, then pushed out of the rack into a water-based cooling-tower system. Water is still required, but not at the levels called for by air-cooled systems.

Diagram of an ICEraQ immersion cooling system by vendor GRC. Source: GRC

Indeed, some purveyors of immersion cooling claim it cuts the energy used to cool a datacenter by up to 95%. Even allowing for marketing hyperbole, the savings could be significant. And they’re not just about reducing the energy required to cool IT; immersion cooling vendors say their approach eliminates the need for raised flooring, cuts down on air-based corrosion of parts, and in general revolutionizes the design of datacenters.

A Growing Market

Immersion cooling has caught on with hyperscalers, users of high performance computing (HPC), cryptocurrency miners, and makers of datacenter gear. Microsoft (Nasdaq: MSFT) has experimented with the technique. A datacenter under construction in Ohio by Standard Power will be cooled by immersive technology from provider Liquid Stack. Intel (Nasdaq: INTC) has partnered with another immersion cooling vendor, Green Revolution Cooling (GRC), to promote the technology, which Intel is testing in its recently announced datacenter research lab. GRC also as partnership deals with Hewlett Packard Enterprise (NYSE: HPE) and Schneider Electric.

A bevy of startups is populating the field, which ResearchandMarkets claims will grow from $399.9 million in 2021 to $1.6 billion by 2027, at a compound annual growth rate (CAGR) of 26.06% between 2022 and 2027. Besides Liquid Stack and GRC, other newbies include Asperitas, Iceotope Technologies, and Submer, to name a few.

Some of these startups are garnering sizeable investments. GRC earlier this year raised $28 million in Series C funding led by SK Lubricants, bringing its total raised to $43 million.

Iceotope, based in Sheffield UK, raised £30 million (approximately $36 million) in a round led by ABC Impact, a private equity firm based in Singapore.

It looks like an ecosystem is forming around this intriguing field, which at the very least indicates demand for more sustainable datacenter technology.