Novel Solar Panels System Generates Electricity Using Fresh Water In Arid Regions

Apr, 2022 - By WMR

The new hydrogel-based solar-driven system successfully grew spinach using water harvested from the air during generating electricity

Remote desert regions normally lack a water source and an electric grid for agriculture. Now a team of researchers at King Abdullah University of Science and Technology (KAUST), Saudi Arabia developed a new system with combination of photovoltaic panels and an absorbent hydrogel. The new solar-driven system succeeded to grow crop using water harvested from air while generating electricity. The team named the system as integrated water electricity-crop co-production system (WEC2P).

The new WEC2P system included connected photovoltaic panels that lie on a hydrogel layer. The gel layer and panel form a lid with downward slope for a metal box containing spout at the bottom. The box needs to be kept open at night so the hydrogel can absorb moisture from the air. In the day time, the box needs to be kept closed. Then, the photovoltaic panel generates electricity when there is sunlight shining on the box, which also heats up the panel and the hydrogel layer. Due to this, the water absorbed at night is evaporated out of gel, and is condensed on the panel’s back. When this liquid water goes off the panel, it takes away additional heat, which provides a cooling effect allowing the panels to operate with 9% more efficiency. Then, the water runs to the bottom of the metal box and out through spray to be collected for drinking or to be used for irrigation.

The team tested the system on a small-scale for two weeks in June, in desert of Saudi Arabia, where the system produced 1,519 watt-hours of electricity and nearly 0.5 gal. (2 liters) of water. This water was further used for irrigation of 60 spinach seeds that were planted in a plastic grow box, out of which 57 grew to a 7 in. (18 cm) of height.