Intelligent Data Centres Issue 08 | Page 54

The rise of liquid immersion cooling and the benefits it offers Liquid immersion cooling is increasing in popularity due to the efficiencies it offers organisations when considered against traditional cooling methods. Diarmuid Daltún, CCO, Submer Technologies, tells us more about the technology and the benefits it offers. W What challenges are data centre operators encountering when it comes to power and cooling? What is liquid immersion cooling and how is it addressing these challenges? The solutions data centre operators have in place today are very inefficient – they are using way more electricity and energy than they should be. They are also coming to the limit of how much they can put in the space of one rack space or one cabinet. With air, they are able to cool up to 30kW, but only by using a mix of methods, such as forced air and rear door cooling. LIC is a method of cooling hardware by having it immersed directly in the primary coolant. In Submer’s case, the coolant is circulated actively around the hardware, taking the heat away from every component (any component which consumes electricity, generates heat). LIC IS A METHOD OF COOLING HARDWARE BY HAVING IT IMMERSED DIRECTLY IN THE PRIMARY COOLANT. 54 Issue 08 The heat is then passed out from the coolant to a secondary cooling loop which is typically a closed water system connected to a dry cooler or a method of heat reuse (e.g. district heating or building heating). What kind of data centre operators are utilising this method? The initial interest is coming from HPC, since they are facing the cooling challenge on a daily basis, due to their dense workload. The LIC method is also thought for any application which is used for research purposes which is likely to put strain on the limits of air cooling (e.g. AI, baking, enterprise, hyperscaler, etc.). How scalable are liquid immersion cooling solutions? Speaking of Submer, our solution is very easily and modularly scalable. Each Submer tank (SmartPod) can dissipate >50kW and can be deployed anywhere, without any preparation of the site. You can place them next to each other or back to back (according to your facility needs) since they occupy very little space compared to air-cooled racks. How does immersion cooling differ from water cooling? Water cooling is a very broad topic. Direct liquid cooling (water piped directly to some components, such as GPU, CPU, etc.) for example, requires a specific type of hardware and another method of cooling inside the building. Direct liquid cooling deals typically with 70% of the heat. Immersion cooling deals with the entire heat footprint, doesn’t care about the shape of the equipment and doesn’t need to be specifically prepared (it only requires a hardware with no moving parts, such as fans). www.intelligentdatacentres.com