Assessing the feasibility of nighttime water harvesting from solar photovoltaic panels in a desert region

Abstract

Photovoltaics has emerged as a crucial and progressively significant contributor to renewable energy generation. Nevertheless, its effectiveness is limited to daylight hours when sunlight is available. This research paper presents an approach to promote dual usage of solar panels beyond daytime operations to facilitate water production. An AWGPV (Atmospheric water generation on PV modules) system is built and operated for nearly a year. During this period, several prototypes were built to produce up to 2.5 L/panel per day without optimizing the energy consumed during direct cooling. A techno-economic assessment was done for the prototype AWGPV system. The prototype system consisting of 3 AWGPV panels connected to the grid was able to produce water at 33 USD cents per liter in Dubai, UAE. If the electricity for direct cooling is reduced, the cost of water can be reduced further. The results point to new avenues to explore methods for reducing the electricity consumption for cooling for achieving further cost reduction. A parameter n-MHI (night Moisture harvesting index) is introduced to evaluate the feasibility and energy demands of harvesting atmospheric moisture through direct cooling. Through a climate-based analysis of various locations, the global potential of this process is explored. The collected water can be used for dust cleaning of solar panels, agrophotovoltaic systems, and other applications where water and electricity generation needs to be decentralized.