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Photonics and thermodynamics concepts in radiative cooling

Nature Photonics volume 16, pages 182–190 (2022)Cite this article

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Abstract

Radiative cooling is a ubiquitous passive process that uses photon heat flow to carry away energy and entropy. Radiative cooling processes have been studied in the scientific literature for many decades, but advances in nanophotonics have enabled recent breakthroughs in daytime radiative cooling, which have inspired intense research efforts in this area. Radiative cooling is now emerging as a frontier in renewable energy research, with important potential for wide ranges of applications. In this Review, we discuss the fundamental photonics and thermodynamics concepts that underlie the processes of radiative cooling. Understanding of these concepts is essential both for the demonstration of cooling effects and for the development of practical technology.

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Fig. 1: Daytime radiative cooling.
Fig. 2: Recent advances in daytime radiative cooling.
Fig. 3: Photonic concepts of radiative cooling in solar cells, outdoor coloured objects and textiles.
Fig. 4: Thermodynamic concepts of radiative cooling.

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Acknowledgements

S.F. acknowledges the support of the US Department of Energy (grant no. DE-FG-07ER46426). W.L. acknowledges the support of the National Natural Science Foundation of China (grant nos. 62134009, 62121005).

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Authors and Affiliations

  1. E. L. Ginzton Laboratory, and Department of Electrical Engineering, Stanford University, Stanford, CA, USA

    Shanhui Fan

  2. GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, China

    Wei Li

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Correspondence to Shanhui Fan or Wei Li.

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S.F. owns shares in Skycool Systems, which seeks to commercialize some of the radiative cooling technology discussed here.

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Fan, S., Li, W. Photonics and thermodynamics concepts in radiative cooling. Nat. Photon. 16, 182–190 (2022). https://doi.org/10.1038/s41566-021-00921-9

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