Desalination: Now an Affordable Option?

As water pollution, urbanization, and the residential and industrial needs for water increases, municipalities are scrambling to find new supplies of fresh water.  Around the world, ground water supplies have been tapped to the point that cities and farms are sinking.  Drought around the world, from Australia to Africa to the American South, has also contributed to a growing consensus that water will be the source of global tensions during the 21st century.

In some regions, most notably the Middle East, desalination plants have provided residents fresh water for decades.  As more areas suffer from drought combined with growing population, desalination has become an option, as in London—but often at a very high cost.  Many balk at desalination for two reasons:  the cost, which is tied to the second, energy consumption—leaving many to wonder whether the energy consumed is worth the results.  One company, however, may have the technology to make desalination a more viable and environmentally acceptable source.

Energy Recovery Inc. (ERI), headquartered in San Leandro, CA, has a process that it claims not only runs at 98% efficiency, but can reduce desalination plants’ energy consumption by 60% to 80%.  The company works on an average of 300 projects around the world annually, often retrofitting older plants with its Pressure Exchanger energy recovery technology.  Like other desalination systems, ERI uses reverse osmosis.  With a combination of high pressure systems,  frictionless hydrodynamic bearing, and a low pressure incoming feed stream, water is forced through the membranes, separating salt and other elements from sea water.  In layperson’s terms, a ceramic rotor floating without creating any friction is the difference between older, more expensive technologies, and ERI’s system, which consumes much less energy.

Yesterday I spoke with GG Pique, President and CEO of ERI.  One way in which ERI’s technology can have a positive environmental impact is evident in Sand City, CA, just outside of Monterey.  The town is home to only a few hundred people, but shopping and tourism brings in about 40,000 daily while employing 4,000.  Using ERI’s system, Sand City’s desalination plant produces almost 600,000 gallons of potable water a day.  Wells drawing water are not in the bay, where they would interfere with marine life, but from four subsurface beach wells.  Generally running during off-peak hours, the new facility can desalinate water at about $3 per 1000 gallons.

Another plant, which will in part use bio-methane for fuel, is in the works in nearby Marina, near the old Fort Old.  The Monterey Bay area has suffered from drought for years, stalling economic development while residents deal with strict water rationing—and with the result that the nearby Carmel River has been decimated, over pumped as these localities search for water.  Pique explained that the scaling of his firm’s technology can help reduce that trend.

I mentioned to Pique that many object to desalination because of the cost, and asked if reduced prices were really a consistent result of plants implementing ERI’s technologies.  He pointed out that use of ERI’s systems in San Diego has reduced the cost of water from $3 a cubic meter (while placing continued strain on the Colorado River) to about 70 cents per cubic meter when plants implement his firm’s desalination products.

ERI maintains a library of case studies on its web site, and has performed well financially since going public in 2008.  Pique explained that more projects with which ERI is involved are using renewable energy to at least in part fuel such operations.  So does desalination finally make fiscal and environmental sense?  Explore ERI’s site and share your thoughts.

Based in Fresno, California, Leon Kaye has written for TriplePundit since 2010. He has lived across the U.S., as well as in South Korea, Abu Dhabi and Uruguay. Some of Leon's work can also be found in The Guardian, Sustainable Brands and CleanTechnica. You can follow him on Twitter (@LeonKaye) and Instagram (GreenGoPost).

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