Solar panel device uses waste heat to purify water

  • 5 years ago
THUWAL, SAUDI ARABIA — Researchers in Saudi Arabia have modified traditional solar panels into a system that cogenerates both electricity and clean water.

Water and energy production are intertwined — a connection known as the water-energy nexus. Cosmos Magazine reports that water is used to produce energy, and in turn, a significant amount of energy is needed to produce clean drinking water.

According to Peng Wang of the King Abdullah University of Science and Technology, solar panels only convert 20% of the light they absorb into electricity; the remaining 80% is released into the air.

To address this, university researchers have designed a system that can use this waste heat to generate fresh, clean water.

The system is made up of a three-layer distillation system attached to the underside of a solar panel.

Waste heat from the panel is directed to the uppermost layer, where it vaporizes seawater. The vapor passes through a porous membrane to the second layer, where it condenses as freshwater. Heat produced during condensation passes through a thermal conduction layer, where the energy is recycled to purify more water.

The stacked system was able to produce 1.64 liters of water per square meter of solar panel surface each hour.

According to the researchers, it's more than double the output of more traditional solar stills. The panel's electricity output was also unaffected by the distillation going on underneath.