Sandia National Laboratories chemical engineer Anthe George with a handful of benthic algae growing in the Salton Sea Biomass Remediation, or SABRE, Project floway system. Photo by Jules Bernstein

Sandia National Laboratories is testing whether one of California’s largest and most polluted lakes can transform into one of its most productive and profitable. Southern California’s 350-square-mile Salton Sea has well-documented problems related to elevated levels of nitrogen and phosphorus from agricultural runoff. Algae thrives on these elements — a fact that causes environmental problems but could also be a solution to those problems.

Sandia intends to harness algae’s penchant for prolific growth to clean up these pollutants and stop harmful algae blooms while creating a renewable, domestic source of fuel. Algae can be easily converted to fuels and chemicals using a Sandia Labs-patented fermentation process.

BETO is funding Sandia’s Salton Sea Biomass Remediation, or SABRE, Project because it will help determine whether algae can be a viable part of the solution to our nation’s need for diverse energy sources. After only a few months, Sandia biochemist Ryan Davis is enthusiastic about the prospects. “The early results we’re already getting from the Salton Sea appear to be superior to results from similar algae systems. It’s really promising.”

When state and local officials gathered by a tributary of the Salton Sea one bright, hot morning in late May, it was to mark the kickoff of the project’s second phase. During the first phase, Sandia partnered with Texas A&M AgriLife Research to test whether a newer method of farming algae could be as productive as an older, more established method.

The newer farming method is called an “Algal Turf Scrubber” floway system, used for growing a collection of native algae species. To the untrained eye, the system looks like a free-standing rain gutter. It gurgles quietly as water is pulsed in waves across a sloped floway. The algae consume the nutrients, and clean water emerges from the lower end.

The system operates using solar-powered pumps, requiring almost zero maintenance, except for periodic algae harvesting which can be done using common farming equipment. Sandia designed the renewable power pump system that provides water to the floway. The technology and components of the floway were developed by a company called HydroMentia Technologies LLC.

Based on early results of the testing in Texas, turf scrubbers can produce a quantity of algae comparable to raceways. And they are a perfect fit for places with acres of inexpensive real estate, nutrient-rich water (no need for additional fertilizer) and tons of sun, like the Salton Sea.

The kind of turf system being tested for the SABRE Project has other benefits. It is growing algae that is native to the area, so it is naturally more resistant to attacks from local pathogens and predators. The algae’s thick texture also lends itself to easy harvesting.

One of the criticisms lobbed at algae as a biofuel source is that it uses too much water. Dr. Davis disagrees with this criticism. “There’s water and then there’s water,” he said. “We’ve shown that we can grow algae in turf scrubber systems using water full of nasty components. And it still thrives.” In other words, there isn’t much that can be done with this water until the pollutants are removed.

Should the SABRE Project prove successful, it could provide a model of remediation for algae blooms nationwide. There are hopes that the Imperial Valley would benefit as well. By covering thousands of acres of dry, receding Salton Sea shorelines with algae crops, turf scrubber operations could reduce widespread air pollution from toxic dust. Algae refineries could also provide new economic opportunities.

Sandia partnered with the Imperial Irrigation District to help get the SABRE Project off the ground. “A proponent of renewable energy and an advocate for the Salton Sea, the district believes projects like this have the potential to make a meaningful difference,” said the district’s Officer of Media Communications Specialist, Marion Champion. “We are very hopeful that this project will yield good, clean renewable energy while providing a natural and safe process to remove chemicals, protecting area wildlife for generations to come.”