Biofuel is better for humans and the environment when the plants used to make the power don’t need valuable freshwater or cropland that could be used instead for food. Often today’s algae-based biofuels are grown in freshwater, but some companies have made the switch successfully to marine algae and a new report says the technique is just as viable on a commercial scale.
Marine algae bio-oil rigs could keep the plant-powered power source from
competing for shrinking fresh water supplies, while greatly expanding
the area available for production.
“What this means is that you can use ocean water to grow the algae that will be used to produce biofuels. And once you can use ocean water, you are no longer limited by the constraints associated with fresh water. Ocean water is simply not a limited resource on this planet,” said Stephen Mayfield, a biologist at UC San Diego who led a study on the feasibility of using marine algal species to produce biofuel, in a press release.
Growing algal biofuels in fresh water raises several problems that salt water algae doesn’t. One, using fresh water creates another food vs. fuel debate, since crops also need fresh water. Plus, humans and livestock need to drink fresh water. All that pressure on potable water is drinking rivers dry, such as the Colorado, and is draining the world’s easily accessible aquifers faster than they are being replenished. Using oceanic algae could also open up the vast oceans as potential bio-oil production areas.
Sapphire Energy, which produces algal biofuel in water-poor New Mexico, states on their website that their operations are already designed to not compete for fresh water. The company already uses salt water, albeit on dry land, and expects to produce 100 barrels per day of algal crude oil in 2013. Sapphire collaborated with UC San Diego on this research.
Fossil fuel extraction and transport operations, such as coal slurry pipelines and hydraulic fracturing of methane deposits (fracking), use tremendous amounts of fresh water. Considering that one main goal of biofuels is to solve the problems created by fossil fuels, growing algae in a way that doesn’t compete for drinking water is another feather in its cap.
Mayfield’s research also suggested that approximately 10 million acres of land in the U.S. that has become too salty for traditional agriculture could be used for algae production.
Further research may demonstrate that leftovers from algal biofuel can be used for animal feed, according to the study published in Algal Research. “We hope to eventually determine whether whole algae, post-oil extraction, may be used as a feed additive to improve animal feeds,” the authors write.
IMAGE: Algae and plankton discolor the waters around the Florida Keys. (NASA, Wikimedia Commons)