Cooling that requires heat rather than an electric motor to run sounds like another attempt to cheat the laws of physics. But researchers at Karlsruhe Institute of Technology and the University of Tsukuba have actually created a working prototype of such a system.
This device uses a shape memory alloy thin film. One layer, made of titanium and nickel, shrinks when heated and mechanically stretches a second layer of film, made of titanium-nickel iron. In turn, it undergoes a reversible phase change and cools. Thus, heat is converted into mechanical motion and motion is converted into cooling. There are no compressors, electric motors or the usual cooling circuits.
In the laboratory, the system is capable of generating temperature differences of up to 4°C when electrically heated. When using an external heat source, the temperature difference is 2.2°C. In particular, scientists stress that hot air from processors or data center servers could be such a source in the future. Of course, the technology is still far from being used in actual devices.