ACR Journal

February | March 2021 Liquid cooling has been around as a technology since the 1960s but has struggled to be widely adopted. Yet this is about to change. Current demands for IoT, artificial intelligence and machine learning, as well as edge applications, are placing new demands on data centers. To put this into perspective, Gartner has predicted that over one million IoT devices are expected to go into operation every hour in 2021. It is crucial, therefore, that data centres are prepared to cope with these new levels of demand, running at maximum capacity while avoiding downtime. This means that data centres need to be designed and managed more eciently to power a new generation of technologies. It is with this goal in mind that solutions such as liquid cooling have an important role to play. Liquid is becoming the status quo When it comes to cooling technologies, there is no ‘one size fits all’ approach. For example, geographical needs can determine priorities based on climatic conditions. There are a variety of cooling technologies out there – established and emerging. But liquid is becoming the preferred choice for eective and ecient heat capture and transport to manage temperatures in increasingly busy data centres. According to Omdia’s LIQUID COOLING 34 Nigel Gore, Global Offerings, High Density and Liquid Cooling at Vertiv looks at the future of liquid cooling What is the future of liquid cooling? Data centre Thermal Management Report 2020, growth of forms of liquid cooling, like immersion, are expected to double between 2020 and 2024. Several factors are contributing to this shift, including edge growth, increasing rack densities, as well as new energy eciency and sustainability requirements. Pure water is being used to maximise data centre cooling as it has a heat transfer value of 4179 J/KgK, much higher than the value of air. These heat properties make liquid cooling an ecient option. And there are dierent forms of liquid cooling available to suit dierent needs, oering much needed flexibility. Liquid cooling can be implemented using one of these methods: ° The cold plated approach: this primarily captures heat from the processors, with new designs extending to other components of the server. This is typically used in conjunction with some form of additional air-cooling in most cases to support ancillary equipment. ° Immersion liquid cooling: this captures the vast majority of the server heat and as such reduces the demand on air-based cooling, including climate control and comfort cooling combined with ecient external heat rejection. Liquid cooling can help businesses cope with unprecedented quantities of demand for compute power, making it hard to understand why it is yet to be widely adopted. It’s not that it is a questionable technology – the issue lies with the fact that, until relatively recently, there simply wasn’t the demand. However, Omdia’s report shows that, in response to increasingly power- intensive compute requirements, data centre operators are now looking for ways to improve eciency around cooling. At Vertiv, we have seen growing demand for liquid cooling deployments across our global customers in 2020. Volume 7 No.2