Improving vapor condensation via copper foam in capillary-fed photovoltaic membrane distillation

The photovoltaic conversion efficiency of solar cells is significantly constrained by temperature rise. Photovoltaic membrane distillation (PVMD) offers a promising solution for simultaneous solar cell cooling and clean water production. However, the present PVMD system is confronted with the challenge of attaining high cooling efficiency and water production sans reliance on fossil fuels. In this work, a novel and zero-carbon PVMD system is introduced and optimized. One notable improvement is the transportation of feedwater to the backside of the solar cell using capillarity instead of a pumping system. Additionally, a porous copper foam condenser with a rough surface is introduced to the PVMD system. This rough surface creates more nucleation sites for rapid vapor condensation, resulting in a water productivity increase from 0.23 to 0.43 kg m⁻² h⁻¹ under 1 sun (=1 kW m⁻²) irradiation. Furthermore, a 5 cm × 5 cm solar cell demonstrates a temperature decrease from 59.9 to 38.3 °C, accompanied by a voltage enhancement from 2.18 to 2.39 V. This work offers an effective strategy for lowering the operational temperature of solar cells and enhancing the overall utilization efficiency of PVMD devices.