Blog: Californian Innovation: Solutions for Salinity with Solar Desalination

Solar Modules

California has not experienced a drought the likes of the current epic crisis since the year 1580 – as evidenced from tree ring growth. Furthermore, at stake are almost half of all U.S. grown fruits, vegetables and the nations leading dairy and nut crops. The future of California’s 44.7 billion dollar agriculture business is indeed facing dire consequences as our food supply and security are in real harm’s way.

Last month, Gov. Jerry Brown introduced California’s Emergency Drought Legislation. Eighty percent of the state’s water goes into agriculture, as much of the land is arid but made fertile with irrigation. Immediate measures are required to protect it. The wave of California’s future is desalination, ground water cleanup and storm water conservation.

For every problem there are at least three solutions, and effectiveness is the bridge to our best friend in the 21st century – innovation.

A couple weeks ago I met Aaron Mandell, the founder and chairman of Sonoma County-based WaterFX. His company is cost-effectively cleaning up salty water using a modular system with solar thermal energy to recover water from a variety of sources for any use.

I asked him how he came up with this system. “When I was first introduced to the water crisis in California, I was blown away by the scope and magnitude of the problem,” he said, adding that he was surprised that other entrepreneurs had not pursued the billion dollar opportunity of replacing the current water infrastructure in California, from the 1960s. “A lot has changed since then, especially as it relates to climate change and our scarce natural resources, so it was very logical to look at what we could do to create a better water delivery system,” he said.

Mandell, an environmental engineer and entrepreneur, has a very refreshing vision for California that “we have all the water we need if we reuse our wastewater.” His modular solar thermal system utilizes the sun’s energy to heat up mineral oil, which generates heat to power a pump. It boils the source water and collects its steam, that steam is the highest quality purified water. This ingenious system concentrates all the salts as solids, which are sold for use in fertilizers and metals.

WaterFX has successfully helped California’s Panoche Water District over the past six months by producing 8 gallons a minute of pure water from saline discharge drainage or agricultural runoff from the world’s most intensive growing region – the Central Valley. The project is now being expanded to provide 2 million gallons a day of freshwater.

Conventional desalination is fuel- or electricity-dependent and up to 50-60 percent of the total water cost can be the energy inputs. “Solar desalination – using the sun to power the water production – has very low operating costs and with scale, the total water cost comes down with improvements in manufacturing, equipment and process technology,” explained Mandell. This is not the case for fossil fuel-desalination, which can rise in cost with the increasing cost of electricity. The solar desalination model achieves more than 95 percent water recovery, collecting the remaining salt to be sold and reused.

Currently in California there’s a vast amount of agricultural run-off water that is toxic with salt concentration, which fallows the soil. All models that I am aware of show that the climate will become drier in the coming decade(s). So with Gov. Brown’s mandate to clean up ground water, WaterFX clearly has an important role to play because solar desalination can cost-effectively achieve it.

Mandell loves the ocean, as several of his previous companies were named after beaches on Nantucket, one of his favorite places in the world, but since moving to California, Bodega Bay has become a pretty special place for him.

The Golden State is a remarkable place that attracts some of the brightest minds and best business people on the globe. I felt very upbeat after a cup of coffee and listening to a plan on solving our fresh water predicament. I couldn’t help but admire this bright-eyed, enthusiastic businessman who attended the University of Vermont and says “Phish is pretty close to my heart – not just their music, but also the culture.”

Earth Dr Reese Halter is a broadcaster, biologist, educator and author of

The Incomparable Honeybee and the Economics of Pollination.