Period heat source gives thermoelectric power a boost


© Shutterstock

Scientists in the US have found a way to improve the efficiency of thermoelectric power generators (TPGs) – devices designed to convert heat directly into electricity.

TPGs require a heat source, a thermoelectric material that converts heat to electricity, and a power generator. Such devices could be used to recycle heat from power plants or motor vehicles, and could even find use in solar energy conversion. Current research is focused on improving the conversion efficiency of thermoelectric materials but, to date, all proposed designs are either difficult to scale up or uneconomical to produce commercially. Yan Yan and Jonathan Malen at Carnegie Mellon University in Pittsburgh, Pennsylvania, are aiming to solve these problems and have instead focused on changing the type of heat source used.

Current TPGs are designed to be used with constant sources that operate at a consistent temperature, but when Malen’s team tried a periodic heat source they found their TPG device worked more efficiently. Malen says ‘our work amounts to a temporal concentration of heat that increases the instantaneous temperature difference across the thermoelectric generator, thereby improving their performance’. He hopes that the work will inspire research into existing periodic heat sources, as well as the conversion of constant sources into periodic sources in order to improve efficiency.

Jian He an expert in thermoelectric materials at Clemson University, South Carolina, US, describes Malen’s work as ‘achieving a significant system-level efficiency enhancement that is practically inaccessible by current materials development’, adding that the prospect of ‘alternating thermoelectricity’ will profoundly impact the application of thermal power generation.

References

Y Yan and J A Malen, Energy Environ. Sci., 2013, DOI:10.1039/c3ee24158k


Related Content

Harvesting heat

27 October 2014 Premium contentFeature

news image

Philip Ball looks at the materials that harness waste heat and turn it into useful energy

Thermoelectric cost analysis

1 July 2013 Research

news image

Cost considerations for thermoelectric generator design

Most Read

First pictures of hydrogen bonds unveiled

26 September 2013 Research

news image

Observation of intermolecular interactions in quinolines could help to settle the nature of this kind of bonding

Copper catalysis overcomes double bond trouble

3 July 2015 Research

news image

Stubbornly stable unactivated internal alkenes become chiral tertiary amine precursors

Most Commented

Collaboration, not competition

29 June 2015 Research

news image

Organic chemist E J Corey talks to Phillip Broadwith about awards, ambition and academic freedom

Z machine puts the squeeze on metallic deuterium

25 June 2015 Research

news image

Pressures similar to those at centre of the Earth forge metallic deuterium in step toward 80-year-old dream of creating metal...