'Smart' metal to boost cooling efficiency by 175%
'Thermally elastic' alloy to replace liquid refrigerants in air-con.
Researchers at the University of Maryland in the US are developing a new ‘thermally elastic’ metal alloy for use in advanced refrigeration and air-con systems.
“The technology has the potential to increase cooling efficiency by 175%, reduce US carbon dioxide emissions by 250 million metric tons a year, and replace liquid refrigerants that can cause environmental degradation in their own right,” said Eric Wachsman, director of the the University of Maryland Energy Research Center (UMERC).
The Maryland team will soon begin testing of a prototype system, with economic stimulus funding from the US Department of Energy. The new grant is part of a programme designed to bring so-called ‘game-changing’ technologies to market.
“Air-con represents the largest share of home electric bills in the summer, so this new technology could have significant consumer impact, as well as an important environmental benefit,” said Wachsman.
The lead researchers on the project – Ichiro Takeuchi, Manfred Wuttigand and Jun Cui, materials science engineers in Maryland’s A. James Clark School of Engineering – have developed a solid coolant to take the place of fluids used in conventional refrigeration and air-con compressors. Their system is believed to represent a fundamental technological advance.
In the next phase of research, the team will now test the commercial viability of their smart metal for space-cooling applications. The 0.01 ton prototype is intended to replace conventional vapour compression cooling technology. Instead of fluids, it uses a solid-state material, namely the thermoelastic shape memory alloy.
This two-state alloy alternately absorbs or creates heat in much the same way as a compressor-based system, but uses far less energy. It also has a smaller operational footprint than conventional technology, and avoids the use of fluids with high global warming potential.
General Electric Global Research and the Pacific Northwest National Laboratory are partnering with the University of Maryland on the project.