Scientists at Sandia National Laboratories are cultivating green algae that might help produce biofuel.
From the beginning of 1950s, the Department of Energy recognized algae as a potential feedstock for energy and biofuels.
“People have been growing algae for centuries for food supplements for use by man and animals,” said lead researcher Cecelia Williams.
“It now has the potential to supply our energy needs too,” Williams added.
The researchers have recently grown green algae in a 12-by-30-foot greenhouse using a simulated dairy effluent, the nutrient-rich liquid remaining after bacterial digestion of dairy manure.
The solids from the digestion of dairy manure can potentially be used to develop fertilizer and feed and the liquid serves as a nutrient source for algae.
The algae are typically cultured for several days, followed by harvesting and dewatering, after which the algal oil is extracted.
The algae produce lipids, the most useful being neutral oil made up largely of triacyglycerides (TAG) that can be converted to biofuels.
Williams said that growing algae for biofuels eliminates many problems associated with traditional biofuels.
“The current generation of biofuels [starch- and sugar-based ethanol and oil crop-based biodiesel] rely on the use of commodity crops and therefore compete for use of food crops, primarily corn,” she said.
“Also, they are very farm-intensive and use a lot of good farming land, fuel and fertilizer inputs and fresh water,” she added.