EnergyBiofuels from algae hold potential, but more work required to realize that potential

Published 5 November 2012

Scaling up the production of biofuels made from algae to meet at least 5 percent — about ten billion gallons — of U.S. transportation fuel needs would place unsustainable demands on energy, water, and nutrients, says a new report from the National Research Council (NRC); these concerns, however, are not a definitive barrier for future production, and innovations that would require research and development could help realize algal biofuels’ full potential

Scaling up the production of biofuels made from algae to meet at least 5 percent — about ten billion gallons — of U.S. transportation fuel needs would place unsustainable demands on energy, water, and nutrients, says a new report from the National Research Council (NRC). These concerns, however, are not a definitive barrier for future production, and innovations that would require research and development could help realize algal biofuels’ full potential.

Algal biofuels are not quite ready for prime time,” said NRC committee member Joel Cuello, a professor in the University of Arizona department of agricultural and biosystems engineering who co-authored the report. “In other words, if scaled up today, the resources that have to go into production would not be sustainable. However, in our report we say that this not a show stopper, because there are technology combinations that can be designed and developed to make the production process more environmentally sustainable.”

A University of Arizona release reports that for algal biofuels to contribute a significant amount of fuel for transportation in the future, the committee said, research and development would be needed to improve algal strains, test additional strains for desired characteristics, advance the materials and methods for growing and processing algae into fuels, and reduce the energy requirements for multiple stages of production.

Biofuels derived from algae and cyanobacteria are possible alternatives to petroleum-based fuels and could help the U.S. meet its energy security needs and reduce greenhouse gas emissions such as carbon dioxide. Algal biofuels offer potential advantages over biofuels made from land plants, including algae’s ability to grow on non-croplands in cultivation ponds of freshwater, salt water or wastewater.

The number of companies developing algal biofuels has been increasing, and several oil companies are investing in them. Given these and other interests, the National Research Council was asked to identify sustainability issues associated with large-scale development of algal biofuels.

Cuello said if current methods were to be scaled up to meet the 5 percent goal, algal biofuel production would consume too much water, energy, and nutrients to be environmentally sustainable at this point. Additional concerns voiced in the report are the amount of land area needed for algae ponds and uncertainties in greenhouse gas emissions over the production life cycle.

For example, to produce those ten billion gallons of biofuel, you would need about thirty-three billion gallons of water,” Cuello said. “That is a huge concern.”

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