Electricity-Free Cooling Prototype Targets Datacenter Heat

A joint research project between the Karlsruhe Institute of Technology (KIT) and the University of Tsukuba has developed a miniaturized, electricity-free cooling technology that could reduce the energy and water footprints of datacenters. As reported by The Register, the researchers published their findings in *Nature Energy* on Friday, August 28, 2026.

The system utilizes elastocaloric cooling, which employs shape-memory alloys that change temperature during phase transitions when mechanically loaded and unloaded. Unlike traditional compression cooling, which uses electricity and harmful refrigerants, or standard thermoelectric systems that remain energy-dependent, this prototype relies on waste heat from the object being cooled—such as a computer processor—to function.

The mechanism uses two ultra-thin nickel-titanium foils. One foil shrinks when exposed to heat, creating mechanical energy that acts as an actuator. This energy is transferred to a second foil, triggering the phase transition that produces the cooling effect. In laboratory tests, the team reported a temperature span of 12.9 K at the refrigerant film level and 4.0 K at the device level, utilizing Joule-heated actuation at 86°C. When exposed to an external heat source of 130°C, the system maintained a device-level temperature span of 2.2 K.

Yi-Ting Hsiau, a PhD candidate at KIT and lead author of the paper, stated that the measurable cooling generated by the heat-driven system proved the principle works beyond theoretical models. Jingyuan Xu, head of KIT’s ZEco Thermal Lab, noted that the team now intends to build larger experimental units to optimize performance and develop compact, sustainable cooling systems. The development arrives as heating and cooling now account for over 40 percent of global energy-related carbon dioxide emissions, according to IRENA.