In what is believed to be a world first, University of South Australia (UniSA) researchers have designed a self-sustaining solar-driven system that evaporates seawater and recycles it into freshwater, growing crops without any human involvement.

It could help address looming global shortages of fresh water and food in the decades ahead. Professor Haolan Xu and Dr Gary Owens from UniSA's Future Industries Institute have developed the vertical sea farm, which can float in the ocean and produce fresh water for drinking and agriculture.

The floating sea farm is made up of two chambers: an upper layer like a glasshouse and a lower water harvest chamber. "The system works much like a wicking bed that household gardeners might be familiar with," Owen said.

"However, in this case, clean water is supplied by an array of solar evaporators that soak up the seawater, trap the salts in the evaporator body, and, under the sun's rays, release clean water vapor into the air. "This vapor is then condensed on water belts and transferred to the upper plant growth chamber."

The system, which is powered only by solar light, has several advantages over other solar sea farm designs currently being trialed, according to Xu. "Other designs have installed evaporators inside the growth chamber, which takes up valuable space that could otherwise be used for plant growth," Xu said.

Read the entire article at Manufacturers' Monthly