Electrocaloric systems

electrocaloric cooling cycle
© Fraunhofer IPM
Calorics + cycle = heat pump: Electrocaloric material heats up when an electric field is applied. When you dissipate the heat to the environment and then remove the field, the material cools down; it can now absorb heat. Built up cyclically, the electrocaloric effect can be used to create a heat pump or a cooling system.

Solid-state-based heat pumps and cooling systems based on electrocaloric materials have the potential to become an environmentally friendly alternative to compressor technology.

How does an electrocaloric heat pump work?

When an electric field is applied to electrocaloric materials, the electric dipole moments in the field align and the material heats up. The heat generated is dissipated via a heat sink, so that the material cools down again to the initial temperature. Once the electric field is removed, the alignment of the electric dipole moments in the field is reduced and the material cools down to a value below the initial temperature. Now it can absorb thermal energy from a heat source. This effect is highly reversible and can be used cyclically, making it possible to realize potentially highly energy-efficient cooling systems and heat pumps.

Central innovation: a novel heat transfer concept

Fraunhofer IPM relies on a patented system concept for the construction of electrocaloric systems that is based on rapid heat transfer using latent heat within a saturated steam atmosphere (heat pipe condition). Heat is effectively transferred to the electrocaloric material and released again by evaporating and condensing a fluid. This makes it possible to achieve thermal power densities that are an order of magnitude higher than in alternative system approaches. In future, this will make it possible to create cost-effective systems with a smaller installation space requirement.

In particular, Fraunhofer IPM is working on:

  • Development and construction of measurement setups for direct measurement of the electrocaloric effect of electrocaloric materials
  • Collaboration to develop improved electrocaloric components
  • Simulation of electrocaloric materials (e.g. thermal finite element simulations to optimize the structure of electrocaloric components) and systems
  • Construction and characterization of electrocaloric systems

We support our industrial customers in the conceptual design and development of caloric systems – all the way to the construction of finished systems for specific applications. We can draw on many years of technological experience, established supplier contacts and the capacity of our highly specialized workshops and laboratories.

Further information

 

Fraunhofer lighthouse project »ElKaWe«

Electrocaloric heat pumps

Six Fraunhofer Institutes are working on the development of efficient electrocaloric heat pumps as an alternative to compressor technology.

 

Applications »Electrocalorics«

 

Efficient heating and cooling without harmful refrigerants