Passively Ultra Cooling Patch Enabling High‐Efficiency Power‐Water Cogeneration

Abstract

Abstract Photovoltaic (PV) systems, which accounted for 75% of global renewable energy capacity in 2023, are limited by the substantial waste heat generated through the photothermal effect, reducing both electricity generation efficiency and panel longevity. In this work, a passive cooling strategy using an ultra‐cooling patch (UCP) that effectively cools down the PV panel is presented, thus achieving an exceptionally high cooling power of nearly 700 W m −2 and facilitating the recovery of over 70% of waste heat for freshwater production. The flexibility and adhesive properties of UCP allow for easy integration with various PV configurations, including flexible panels. In addition, the UCP can be easily reconfigured into a fined structure, enabling modifications to the heat transfer pathway. This passively intensifies the heat dissipation of the PV panel, further enhancing the cooling performance. As a result, a remarkable temperature reduction of 29 °C for the PV panel is achieved, which in turn results in an impressive increase in maximum power density of over 28%. Moreover, outdoor experiments on a ≈1 m 2 PV panel validated the cooling performance and practical applicability. This study offers a solution with commercial potential to relieve the energy‐water crisis, owing to its high efficiency, scalability, and cost‐effectiveness.