Study Suggests Important Tradeoffs for Algae Biofuel

February 17, 2010

As the push for biofuels grows, it will be essential to dig into the devilish details for each fuel source.

In the case of algae, a study published Jan. 19, 2010, in Environmental Science & Technology highlighted several findings that some advocates may want to ignore or downplay, but which could be essential for a broader audience to be aware of as research and development continue.

The University of Virginia researchers found that algae-based biofuel uses more energy and water and emits more greenhouse gases than other biofuel sources such as switchgrass, canola, or corn. On the other hand, algae has a high energy yield, and growing it wouldn't significantly affect food crops, as does corn.

"Environmental Life Cycle Comparison of Algae to Other Bioenergy Feedstocks," Clarens et al., Andres Clarens, 434-924-7966.

To counteract some of algae's negative effects, the authors recommend siting algae production sites next to wastewater treatment plants so that the excess nitrogen and phosphorous from those sources can be used as food for the algae. That kind of coexistence would also reduce the costs the wastewater plant now has for mitigating its excess nitrogen and phosphorous, and could plausibly reduce the energy, water, and greenhouse gas footprints of both facilities.

Similar interlinked development already occurs with uses such as the capture and use of methane released by landfills, or heat generated by power plants. However, this kind of co-dependence typically doesn't get much positive emphasis in the U. S., and is often specifically precluded, or made more difficult, by our legal, financial, and planning frameworks. These barriers to many kinds of more sustainable development suggest a much broader line of inquiry you may want to look into and cover.

If you're sticking with algae and biofuels, though, a multi-pronged effort involving EPA, USDA, DoE, and others that President Obama announced Feb. 3, 2010, involves many other sources of information you can use to localize your coverage, or get a better handle on the big picture. In just the past few months alone, the federal government has committed to hundreds of millions of dollars tied to various biofuels endeavors.