Uncertainties in supply and price of non-renewable energy sources, and the environmental concerns of adverse effects of fossil fuels have led researchers to further explore the realm of alternative fuel sources.
Recent microalgae research at Oklahoma State University’s Robert M. Kerr Food & Agricultural Products Center has done just that.
“Currently, biofuels such as bioethanol and biodiesel are mainly produced from corn and vegetable oils in the U.S.,” said Nurhan Dunford, FAPC oil/oilseed specialist and OSU department of biosystems and agricultural engineering professor. “Today, there is no bioethanol production facility in Oklahoma because the amount of corn grown in the state cannot meet the needs of a bioethanol production facility. At this point, these operations have to rely mostly on feedstock coming from outside the state.”
With the local alternative feedstock need in mind, Dunford and her group of student and faculty researchers have been examining non-food crops such as microalgae as potential biofuel and bioproduct feedstocks.
“Microalgae are microscopic organisms found in both marine and freshwater environments,” Dunford said. “Various types of algae are among the most efficient plants to convert solar energy to chemical energy, and microalgae can accumulate a wide range of commercially important products like oil, sugar, protein, cellulose and high value functional bioactive compounds.”
Microalgae, the non-food feedstock, offer diverse uses. “With microalgae, we can clean waste water while generating biomass,” Dunford said. “Microalgae are capable of absorbing excess plant nutrients from waste water and use CO2 for producing oil, biomass and even useful high value compounds.”
As an alternative to land planted crops, microalgae can grow and thrive in water sources such as ponds or animal waste streams.
“Microalgae systems use far less water than traditional oilseed crops,” Dunford said. “By use of microalgae, it would take only 1 to 3 percent of the existing U.S. crop area to replace half of the petroleum based transportation fuel with biodiesel. More importantly, microalgae do not compete with cropland.”
Research shows many microalgae strains can accumulate as much or more oil than oilseeds.
“Microalgae may have 30 to 70 percent oil, based on dry algal biomass, while soybeans contain about 20 percent oil,” Dunford said. “The high oil content and rapid biomass production make microalgae a very attractive renewable source for bioproduct manufacturing.”