KACST), Saudi Arabia’s national research and development organization, “announced a research collaboration aimed at creating a water desalination plant powered by solar electricity, which could significantly reduce water and energy costs.” (Photo of a concentrated photovoltaics unit at IBM Research courtesy of IBM)
IBM’s announcement explains that “a new, energy efficient desalination plant with an expected production capacity of 30,000 cubic meters per day will be built in the city of Al Khafji to serve 100,000 people.” Moreover, “KACST plans to power the plant with the ultra-high concentrator photovoltaic (UHCPV) technology that is being jointly developed by IBM and KACST; this technology is capable of operating a CPV system at a concentration greater than 1,500 suns. Inside the plant, the desalination process will hinge on another IBM-KACST jointly developed technology, a nanomembrane that filters out salts as well as potentially harmful toxins in water while using less energy than other forms of water purification.”
Reverse osmosis and thermal technology, operating at a cost ranging from 2.5 to 5.5 Saudi Riyals per cubic meter, are the two most commonly used methods for seawater desalination, according to KACST scientists. The goal of this project is to significantly reduce the cost of desalinating seawater at these plants by combining solar power with the new nanomembrane.
“Because over 97 percent of the world’s water is in the oceans, turning salt water into fresh water cost effectively and energy efficiently offers tremendous potential for addressing the growing worldwide demand for clean water. One of the most efficient means of desalination is reverse osmosis. But there are obstacles to unlocking this reserve -- principally bio-fouling, degradation by chlorine and low flux challenges. The KACST / IBM joint research focuses on improving polymeric membranes through nanoscale modification of polymer properties to make desalination much more efficient and much less costly.”