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arXiv · 2010.02426

Concentrated Radiative Cooling

Joseph Peoples·Yu-Wei Hung·Xiangyu Li·Daniel Gallagher·Nathan Fruehe·Anil Yuksel·James Braun·Travis Horton·Xiulin Ruan
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Abstract

A fundamental limit of current radiative cooling systems is that only the top surface facing deep-space can provide the radiative cooling effect, while the bottom surface cannot. Here, we propose and experimentally demonstrate a concept of "concentrated radiative cooling" by nesting a radiative cooling system in a mid-infrared reflective trough, so that the lower surface, which does not contribute to radiative cooling in previous systems, can radiate heat to deep-space via the reflective trough. Field experiments show that the temperature drop of a radiative cooling pipe with the trough is more than double that of the standalone radiative cooling pipe. Furthermore, by integrating the concentrated radiative cooling system as a preconditioner in an air conditioning system, we predict electricity savings of $>75\%$ in Phoenix, AZ, and $>80\%$ in Reno, NV, for a single-story commercial building.

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Joseph Peoples, Yu-Wei Hung, Xiangyu Li, Daniel Gallagher, Nathan Fruehe, Anil Yuksel, James Braun, Travis Horton, Xiulin Ruan. 2020-10-06. Concentrated Radiative Cooling. https://arxiv.org/abs/2010.02426

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