Waste Heat

Waste heat is by necessity produced both by machines that do work and in other processes that use energy, for example in a refrigerator warming the room air or a combustion engine releasing heat into the environment.

  • Electricity from waste heat made possible by ceramics

    Where conventional materials reach their limits, ceramics can display their excellent properties. Functional ceramics – so-called thermoelectric materials – can convert waste heat directly into electricity, for example, in high-temperature processes. At the Hannover Messe 2016, Europe's largest ceramics research institute presents for the first time a system that demonstrates the reliable functionality of thermoelectric ceramic modules developed at Fraunhofer IKTS. (Hall 6, Booth B16)

  • More Efficient Energy Harvesting With Magnets

    Thermomagnetic generator on a laboratory scale. Photo: IFW Dresden

    Scientists at the Leibniz Institute for Solid State and Materials Research Dresden (IFW) have developed a new magnetic generator to convert waste heat into electricity. A clever arrangement of the components has succeeded in improving the electrical yield by orders of magnitude. Thus thermomagnetic generators qualify for application-suitable technology for the energy harvesting of from waste heat. Many processes in everyday life and in industry generate waste heat that is not hot enough to be used effectively. As a rule, it is discharged into the environment unused, for example, in the case of large IT servers or at the exit of power plant cooling towers. To date, there are very few technologies available for the conversion of low temperature waste heat into electricity. 

  • New Material Makes Cooling Devices More Energy-efficient

    For their tests, the scientists coated a conventional heat exchanger with the new material, in cooperation with colleagues from the Fraunhofer Institute for Solar Energy Systems. Photo: Dirk Lenzen

    Waste heat from industry can often not be utilised because of its low temperature. With this material, it can be used in environmentally friendly cooling systems for example in the field of building technology. The research team from Kiel will present its material and its applications at the Hannover Messe 2018. Cooling devices are considered to be power guzzlers, in which polluting refrigerants are still used, even after the ban on chlorofluorocarbons (CFCs). An environmentally friendly alternative are systems which use water instead.