Solar Powered Desalinator
By Veronica DicksonPublished October 5, 2015By Veronica Dickson, 10/5/15
Ranging 900 miles on the Western coast of the United States, the Golden State boasts cliff-lined beaches, staggering redwood forests and yields enough agricultural riches to feed the entire country. What's the catch? This veritable Garden of Eden, our own California, is ushering in the fourth year of a megadrought. With only a year of water left in California's reservoirs, rationing and scrimping on superfluous water use won't be enough to carry the state through the drought. Current forecasts anticipate no end in sight; in fact, NASA estimates that in order to recover, California must be able to generate 11 trillion gallons of water, or 1.5 times the maximum volume of the largest U.S reservoir.
California relies heavily on the Colorado River basin and its many tributaries to provide freshwater for its citizens and agricultural sector. However, the over-construction of dams and reservoirs along the length of the river has reduced its flow and water level has been steadily and noticeably dropping. This, along with reduced snowmelt, has led California to consider alternative sources in order to recompense for its lack of water.
California isn't the only victim of severe drought. Australia suffered through recurrent and seasonal drought dating from 1995-2009 and Iran is facing water deficiency so severe that 70% of the population may be forced to abandon the country, according to the Washington Times. A method to combat drying water reserves is the process of water desalination. Essentially, this removes all brine and other minerals in seawater through a process of evaporation. In 2011, Melbourne completed a seawater desalination plant capable of supplying a third of the cities' water needs. The inherent problem with this technology is its high energy and pecuniary cost.
Cue, Ã¢â‚¬ËœWaterFX', a California-based water producer committed to building sustainable solar desalination systems that could potentially lead California out of the drought without depleting Earth's remaining natural energy resources. Currently, only one percent of the world's desalination is powered by renewable sources of energy, however, WaterFX has conceived its own "engineered aquifer" that is powered solely through solar thermal energy: the Aqua4. The Aqua4 is a Concentrated Solar Still (CSS) that can rapidly evaporate and distill water using a concentrated solar thermal collector in order to generate a whopping 65,000 gallons of freshwater per day- distilling a variety of water sources, not only seawater. The water treatment leaves no liquid discharge and the plant turns all excess salt and minerals into usable and nontoxic byproducts.
WaterFX isn't the only enterprise looking to create sustainable solar desalination plants. The 2013 World Future Energy Summit in Abu Dhabi also harkened the conception of a new project under the Abengoa company, says Clean Technica. This Ã¢â‚¬ËœAdvanced Water Technology' (AWT) is a project aimed at creating a solar desalination plant powered by a 15 megawatt solar array engineered by the King Abdulaziz City Science and Technology agency. Notoriously arid, Saudi Arabia currently burns 1.5 million barrels of oil at desalination plants. These plants provide 50-70 percent of the region's water, proving the dire need for renewable sources of water distillation.
WaterFX will not only be able to provide California much needed water for personal consumption, but it may prove to be an even bigger boon to the agricultural market. Crops suck all freshwater from the soil, leaving excess amounts of salt and minerals and reducing the fecundity of the area. The process of irrigating thirsty plots of land has been dangerously neglected and the effects are starting to show. Famously, the almond industry is suffering from salt-laden soil that prevents healthy tree growth. WaterFX expects at least 10% of all current farmland in California will have to be retired unless the salts are removed from the soil. Not only will the contaminated groundwater halt crop productivity, but it could irreversibly damage the natural habitat and wildlife of the entire Central Vvalley region.
WaterFX remains the only enterprise in the country to be sustainably distilling water at very low cost. In fact, the plant produces water at a quarter of the cost of conventionally desalinated water: $450 an acre-foot versus $2000 an acre-foot. Solar powered desalination remains an emerging technology, but given the current state of the world's water needs and a thirsty, exponentially growing population, the efforts of WaterFX and the AWT shows incredible promise.