Comments: Running Hot and Cool for a Power Boost

Abstract

_ Have data center operators become the major proponents of nuclear power? A flurry of recent announcements suggests so. But three major industry players are leveraging their oil and gas expertise to offer another process to help data center operators run their sites more sustainably—immersion cooling liquids. Nuclear power took top billing in the past 2 months with Amazon and nuclear reactor company X-Energy announcing a collaboration to bring online more than 5 GW of small modular reactors (SMRs) in the US by 2039. Google and Kairos Power will collaborate to deploy 500 MW with SMRs by 2030. Kairos will build them, then sell energy and ancillary services to Google under power purchase agreements (PPA). Microsoft has an eye on the restart of the retired 835-MW Three Mile Island Unit 1 and signed a 20-year PPA with Constellation Energy which owns the plant and plans to finance the work required with the PPA, its largest ever. These early plans could boost the available power supply while lowering carbon emissions, but hurdles remain. The Nuclear Regulatory Commission (NRC) must approve commercial deployment; SMRs are in relatively early stages and regulatory frameworks are evolving; the need for public acceptance; and the NRC comes into play again to regulate the management and disposal of radioactive nuclear waste. In other words, this will not be a speedy solution. Immersion Cooling for Data Centers—Shell, ExxonMobil, and BP Although the practice of liquid cooling isn’t a new concept in the oil and gas industry which uses water, oil, cooling towers, seawater, and engineered liquids to handle heat in various processes and plants, data center operators are exploring the use of a muscle car version—immersion cooling. Immersion cooling is gaining broader attention and consideration. Data Center Frontier called it “ready for its big moment.” The Cleantech Group forecasts that the market for immersion cooling could grow from $270 million to $2.54 billion by 2032. The process entails submerging servers with modified hardware into a bath of nonconductive liquid (e.g., fans are removed, protective coatings are applied, a controlled temperature range of the liquid is maintained) to allow the heat generated by components to be transmitted into the fluid and cooled using either a single-phase or two‑phase method. In the single-phase process, a thermally conductive dielectric liquid is used. It is circulated through immersion tanks, using pumps, to an external heat exchanger, then it is returned to the tanks. The two-phase method is more complicated. The dielectric fluid is one that will change from a liquid to a gas at a relatively low temperature (lower than the operating temperature of the electronic components). Because the immersion fluid has a low boiling point, the boiling causes the fluid to change state, from liquid to gas. This phase change is an efficient method of removing heat due to the vaporization process. As immersion cooling gains traction as a sustainable and efficient alternative to traditional air cooling, major energy companies are stepping in to drive innovation in this technology. Shell, ExxonMobil, and BP, each with their own specialized immersion cooling fluids and collaborative ventures, are helping to advance the commercial adoption of immersion cooling in data centers worldwide. Shell Lubricants joined Green Revolution Cooling (GRC), one of the first companies to develop immersion cooling, as one of the first members in GRC’s ElectroSafe Fluid Partner Partner Program in 2022 and has deployed GRC Immersion Cooling Systems in its Houston data center and with partner Asperitas in a high-performance cluster (HPC) in its Amsterdam facilities. Shell’s single-phase, synthetic immersion fluid is based on its proprietary gas-to-liquids technology. It is conducting pilot programs with Microsoft and Alibaba in China and working with Infosys to create an integrated immersion cooling system. ExxonMobil launched its “portfolio of synthetic and nonsynthetic fluid” last October. In April 2024, the company announced it is working with Intel to develop new liquid cooling technologies for data centers. BP’s lubricant subsidiary, Castrol, is offering a range of single-phase immersion cooling fluids. It is working with Submer on future fluids and has set up a UK test center for potential customers at its headquarters. Castrol joined the Research Institutes of Sweden (RISE) to study thermal management and materials science using RISE’s data center test bed. Immersion cooling may deliver efficiency gains and lower power demand at a lower cost than newbuild nuclear power, but will it be enough? Or is it a stopgap until power generation ramps up? Note: I’m pleased to announce that Trent Jacobs has been promoted to the position of JPT managing editor and will be this column’s new voice starting with our December issue.