Library Subscription: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

HIGH-PERFORMANCE PLASMONIC SELECTIVE ABSORBERS FOR HIGH-EFFICIENT AND LARGE-SCALE SOLAR-THERMAL CONVERSION

Get access (open in a dialog) DOI: 10.1615/IHTC16.nee.023192
pages 7633-7642

Abstract

Recently, solar-thermal energy conversion has drawn renewed interest to harvest the abundant solar energy due to its great potential in enhancing the solar energy utilization efficiency. A spectrally selective absorber is the key technology in a solar-thermal system to harness the entire solar spectrum and suppress thermal re-radiation at elevated temperatures. Owing to the tunable spectral selectivity, high absorption, and ultrathin structure, plasmonic metamaterials has been extensively studied for solar absorbers. However, plasmonic metamaterial absorbers (PMAs) with superior high-temperature solar-thermal performance and great potential for large-scale production remains challenging. In this study, a tri-layer plasmonic metamaterial absorber (PMA) with triangular high-loss nanodisks is proposed, showing a high solar absorptance of 89.0% over the visible-NIR range. This broadband near-perfect absorption is achieved due to the combination of plasmonic resonance and material losses. Because of the low IR emission of each constitunet layer, the thermal emittance of the PMA is greatly suppressed, being only 14% at an extremenly high temperature of 1300 K. As a result, a high solar-thermal conversion efficiency of 65% at 100 suns and 1300 K is achieved, which outperforms most of the state-of-the-art solar selective absorbers. Besides, the ultrathin (240 nm) PMA can be easily heated up to the high target operating temperatures due to its large surface-to-volume ratio.