Johnson Controls has announced a “multi-million-dollar” strategic investment in two-phase direct-to-chip liquid cooling firm, Accelsius.

“With the sharp growth in AI, cooling innovation has become a front-line imperative to meet the increasing demands of high-density data centers,” said Austin Domenici, vice president and general manager, Johnson Controls global data center solutions. “Leveraging our leading capabilities, our mission is to drive the industry forward to unlock new levels of energy efficiency across the cooling chain.”

Texas-based Accelsius was originally founded in 2022 by Innventure to commercialize technology developed by Nokia's Bell Labs that had not been productized.

Its NeuCool system sees vaporators (also known as cold plates) mounted directly to targeted hot-spot chips. Dielectric refrigerant flows through the vaporators, where it nucleates into a vapor, which then travels to a CDU and condenses back into a liquid in a closed-loop system, then returning to the vaporator for additional cooling.

Direct-to-chip systems usually rely on water, which has a high heat capacity, but Accelsius is using a dielectric coolant, allowing it to boil in the circulating system to remove more heat.

“With power-dense AI workloads, data centers are moving to liquid cooling,” said Josh Claman, CEO of Accelsius. “Our two-phase, direct-to-chip (D2C) cooling solutions use non-conductive fluids in highly efficient loops to stay ahead of the demanding power-dense AI and HPC workloads. This technology enables 35 percent OpEx savings over single-phase direct-to-chip and eight–17 percent total cost of ownership savings.”

Johnson Controls provides and deploys data center solutions across more than 150 countries. Its products include data center cooling tech under the Silent-Aire brand.

Accelsius has deployed its technology at several data center labs, and recently posted on LinkedIn that its NeuCool Thermal Simulation Rack is headed to London for deployment at Telehouse's new Liquid Cooling Lab. It has also deployed a cooling system to an Equinix lab in Virginia and at Park Place Technologies' new facility in Cleveland, Ohio.

Accelsius recently released a two-phase cooling reference design, developed in collaboration with Jacobs. The reference data center concept demonstrates that facilities planning to use single-phase direct-chip cooling could transition to two-phase systems without requiring complete facility redesigns.