Technologies for the energy transition

Heat pumps are an essential part of the energy transition as they enable sustainable climate control, for example by using electricity generated from renewable sources. In the Fraunhofer Flagship Project Electrocaloric Heat Pumps (ElKaWe), six Fraunhofer institutes are working on the development of electrocaloric heat pumps for heating and cooling. Possible areas of application include buildings, domestic and industrial refrigerators, and air conditioning systems in cars. Electrocaloric heat pumps promise high efficiency and do not require harmful refrigerants. The project began in October 2019 and will end in December 2024.

Partner institutes

Fraunhofer IPM (project management), Fraunhofer IAP, Fraunhofer FEP, Fraunhofer IAF, Fraunhofer IKTS, Fraunhofer LBF

Fraunhofer IAP is developing basic building blocks for such heat pumps, including electrocaloric materials and multilayer components. The materials are based on polymers with polar molecular groups. These, for example, join together in polar crystalline phases in the material and can be aligned in the direction of the field lines by applying a strong electric field. Once the electric field is switched off, they can move freely again. During these processes, the material releases or absorbs a certain amount of heat. Precisely timed variations in the strength of the electric field applied to multilayer components in a heat pipe system result in a heat pump that can generate both heat and cooling.

“Electrocaloric heat pumps have the potential to play a key role in achieving climate targets and significantly speed up the heating transition.”

Dr. Michael Wegener, Head of the Sensors and Actuators Department at Fraunhofer IAP