Billions of vapor-compressor devices employing potent greenhouse gases and with moderate efficiencies are responsible for ~8% of overall CO2-equivalent emissions. With this number increasing unceasingly and emerging regulations worldwide banning these fluids, developing more sustainable coolers and heaters is an urgent scientific and engineering challenge. This is leading to increasing efforts on this topic, like the “Clean and Efficient Cooling” Pathfinder Challenge EU call, aligned with the European Green Deal. According to a US DoE report, solid-state caloric materials are among the most promising alternatives. Although commercial competitiveness has yet to be achieved, the continuous improvement of figures of merit and an increasing number of publications and patents year after year are encouraging. This Symposium aims to bring together the state-of-the-art in the field of solid-state calorics, namely magnetocaloric, electrocaloric, mechanocaloric and multicaloric materials and devices, where new and improved solid refrigerants and designs will be presented to the community. From condensed matter physicochemistry to applications, from the atomistic scale to the macroscale, experimentally or theoretically, Symposium contributions will report on caloric materials including magnetocaloric behavior of new alloys at first-order or second-order transitions, in the cryogenic or room temperature regimes; novel lead-free electrocaloric ceramics, first-order or relaxors, and highly responsive polymers; fatigue-resistant shape-memory alloys and polymers for elastocaloric applications, and powerful barocaloric materials that respond reversibly at reduced pressures. Devices operating with passive or active regeneration and/or cascade modes and/or work recovery, and optimized material shapes for heat exchange will be also discussed. Other thermal-related applications of caloric materials (waste heat recovery, power generation, etc.) may be also presented.

thermal conductivity