Soybeans and corn have long dominated the biofuels arena, leaving unassuming, unicellular algae overlooked as a viable energy crop. Far more efficient than their agricultural counterparts, algae are also a biological sink, consuming the carbon dioxide we spew into the atmosphere. The more CO2 algae consume, the more they reproduce and grow into a rich source for biofuels, forming a beautiful, green, and gooey cycle.
The vitality of algae relies on carbon dioxide. CO2 emissions from industrial plants can be pumped through algal screens, reducing emissions into the atmosphere by 40 to 80 percent and feeding one of the most efficient biofuel sources known to scientists. The captured CO2 emissions are released when the algae biofuel is burned, but because the CO2 waste is recycled, it replaces a fossil fuel.
The oil in algae can be converted into biodiesel and its carbohydrate components into ethanol. Both burn cleaner than coal or petroleum, and neither relies on deforestation and land depletion like most biofuels. While an acre of oil-palm trees, now the world’s largest source of biodiesel, produces approximately 650 gallons of oil, algae has the potential to produce more than 10,000 gallons of oil per acre.
Start-up costs are high to mass-produce algae, a plant that’s fussy about temperature and levels of CO2. But the payoff could be vast.
Michael Briggs of the University of New Hampshire Biodiesel Group hypothesizes in his 2004 report that one-eighth of the Sonoran Desert in the southwestern United States, if dedicated to algae farming, could supply the transportation fuel needs of the United States.
|Margit Christenson wrote this article as part of Stop Global Warming Cold, the Spring 2008 issue of YES! Magazine. Margit is a YES! editorial assistant.|