Fridges of the future
Domestic refrigerators account for 5 % of electricity consumption; hence new regulations encourage development of more efficient appliances. The candidate technology of magnetic cooling offers electrical efficiency combined with gasless operation, meaning minimal environmental impact. The EU funded ELICIT (Environmentally low impact cooling technology) project developed a commercial refrigerator product. The system incorporates magnetic cooling technology, whereby the presence of a changing magnetic field alters the temperature of solid refrigerants. The technology replaces all gas-related systems in current refrigerators. Partners focused on system optimisation, benchmarking and validation, life-cycle optimisation, plus documentation of regulation and standards. ELICIT members developed a marketable product that incorporates various systems developed within the project, especially the magnetic cooling engine. The final product, a 155-litre under-counter model, was demonstrated at an international technology exhibition. Development testing of pumps and heat exchangers confirmed performance according to the required specifications. Although the magnetic heat exchanger did not fully meet operational requirements, the system achieved an unprecedented level of robustness and reliability. Researchers anticipated that the specifications could be achieved with one more round of development. Magnetic cooling was confirmed to effectively integrate into existing refrigerator platforms with little impact on design. Testing demonstrated that the pump and heat exchangers met the requirements for a high-efficiency device. Reliability was sufficiently high to allow for consideration of system control strategies. Researchers confirmed the suitability of current controller technologies for compressor-based cooling. Simulation tools developed within ELICIT were effectively used with each of the refrigerator components. Researchers created web-based versions of the tools using the Virtual Obeya software developed by the POLIMI project. Use of the tools demonstrated the environmental and cost-effectiveness potential of the final refrigerator product. Modelling results confirmed the viability of the technology compared to gas compressor technology. Researchers also showed that no regulatory barriers restrict the eventual adoption of magnetic cooling technology for domestic use. However, the final product will have to comply with several existing standards. ELICT proved the potential of magnetic refrigerator technology, use of which will reduce atmospheric pollution.
Keywords
Refrigerator, magnetic cooling, environmental impact, ELICIT, heat exchangers
