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arXiv · 1804.10736

Accelerating vapor condensation with daytime radiative cooling

Ming Zhou·Haomin Song·Xingyu Xu·Alireza Shahsafi·Zhenyang Xia·Zhenqiang Ma·Mikhail Kats·Jia Zhu·Boon S. Ooi·Qiaoqiang Gan·Zongfu Yu
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Abstract

Vapor condensation plays a crucial role in solar water-purification technologies. Conventional condensers in solar water-purification systems do not provide sufficient cooling power for vapor condensation, limiting the water production rate to $0.4 L m^{-2} hour^{-1}$. On the other hand, radiative dew condensation, a technique used by existing radiative dew condensers, only works at nighttime and is incompatible with solar water-purification technologies. Here, we develop daytime radiative condensers that reflect almost all solar radiation, and can thus create dew water even in direct sunlight. Compared to state-of-art condensers, our daytime radiative condenser doubles the production of purified water over a 24-hour period. The integration of our daytime radiative condenser with solar water-purification systems can increase the water production rate in sunlight from $0.4 L m^{-2} hour^{-1}$ to more than $1 L m^{-2} hour^{-1}$.

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Ming Zhou, Haomin Song, Xingyu Xu, Alireza Shahsafi, Zhenyang Xia, Zhenqiang Ma, Mikhail Kats, Jia Zhu, Boon S. Ooi, Qiaoqiang Gan, Zongfu Yu. 2018-04-28. Accelerating vapor condensation with daytime radiative cooling. https://arxiv.org/abs/1804.10736

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