UK scientists work on ‘super-fridge’
Scientists at the National Physical Laboratory (NPL) and Imperial College are working on a project which they say “could completely change the refrigeration industry”.
Traditional refrigeration methods could be replaced by a more efficient and environmentally friendly cooling alternative which uses the electrocaloric effect to develop new methods of cooling.
The electrocaloric effect is a phenomenon in which a material changes temperature under an applied electric field.
Current domestic refrigeration uses vapour compression. Freon gas, for example, can be cooled and condensed into a liquid. This liquid then absorbs heat from the refrigeration area, causing it to re-evaporate, where it begins the cycle again.
These chemicals can be harmful to the environment when disposed of or if they leak. The method also has low efficiency, requiring high energy input to create adequate cooling.
Thermoelectric and magnetic cooling technologies have been put forward as environmentally-friendly alternatives to vapour compression. However, these technologies struggle to compete with vapour-compression due to intrinsically low energy efficiency (maximum 10%), and the need for large and expensive magnets to generate the magnetic fields needed to run magnetic coolers.
However, an electrocaloric cooler, says Maciej Rokosz – PhD student at NPL and Imperial, “could potentially deliver higher efficiency than vapour compression – as the creation of an electric field requires less energy than the compression process to create the same level of cooling.”
“It could also offer reduced size and weight, making it viable for applications like cooling electronics,” said Rokosz.
According to Tatiana Correia, a scientist at NPL who is leading the project: it is possible over the next three years to develop “the first electrocaloric refrigerator ever to operate close to room temperature”.
NPL is also leading a new multimillion pound project funded by European Metrology Research Programme, METCO (Metrology of Electro-Thermal Coupling) which brings together Europe’s leading research centres and industry to develop unique capabilities for the traceable and accurate measurements of electrocaloric effect in materials.
“We are confident that our design ideas, combined with the expertise we have at NPL and Imperial, will be able to develop a viable cooler,” said Correia.