Cool solution

Traditional refrigeration is based on vapour compression, a continuous cycle of expansion and compression of chemicals. This process is very inefficient in terms of high energy requirements and it is also too large to feature directly in an electronics system. NPL's work centres round the electrocaloric effect, a phenomenon in which a material changes temperature under an applied electric field. Maciej Rokosz, a PhD student at NPL and Imperial, commented: "An electrocaloric cooler 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." Project leader at NPL is Tatiana Correia (pictured), who expanded on this possibility. "Currently, most electronics use heat sinks and fans for cooling. These are passive coolers, which limit the rise of temperatures above ambient. An electrocaloric cooler would pull heat out of the thermal load and so be able to reach below ambient temperatures – allowing the creation of specific temperatures most suited to electronic operation. "An electrocaloric cooler could be integrated into individual chips where they would cool the whole chip or target specific hot spots, unlike fans which must be external to the circuit. This will be important as circuits get smaller. "It is too early to say how this type of cooler compares with heat sinks and fans, but we expect efficiency to be pretty high. It is also too early to say what the cost of a final device would be, but raw materials for electrocaloric media are reasonably cheap, so we believe this will be a cost effective cooling solution."