Don’t Dismiss Biofuels From Algae

A letter to the editor disparaged the “many square miles of glass-covered or huge plastic-bag structures” required for production of biofuels by algae (C&EN, Feb. 6, page 4). This is poorly researched!

Data from the Department of ­Agriculture show 92.3 million acres plant­ed in corn in 2011 (nass.usda.gov/Newsroom/2011/06_30_2011.asp), much of it wasted in making ethanol. Even Congress at last realized that ethanol from corn is a bad way to make biofuels. The following data are from a website of an algae biofuels consortium (algae.ucsd.edu/potential/algae-qanda.html): “The U.S. consumes 140 billion gal per year of liquid fuel. Algae can produce 3,000 gal of liquid fuel per acre in a year, so it would take 45 million acres of algae to provide 100% of our liquid fuel requirements.” With less than half the acreage that is planted in corn, we could meet all of our liquid fuel needs. This website points out that “algae produce a variety of fuel and fuel precursor molecules, including triglycerides and fatty acids that can be converted to biodiesel, as well as lipids and isoprenoids that can be directly converted to actual gasoline and traditional diesel fuel.” The latter is telling; biodiesel “burns hotter than diesel, [so that] nitrogen oxide (NO_x) emissions are actually higher and up to nearly 3.5 times that of gasoline” (energyjustice.net/biodiesel). Isooctane, the basis point of 100-octane fuel, has a branched pattern like isoprenoids.

Thus, gas-electric hybrids like the Toyota Prius are more conducive to fossil-fuel independence, in an algae-biofuel-based economy, than highly touted electric cars, which require electricity from conventional power plants. A 477-page report describes use of algae for reducing nitrogen and phosphorus in sewage: (oilgae.com/ref/report/wastewater_treatment/wastewater_treatment.html); even arid land is productive for growing algae in sewage.

Nevada covers 70.8 million acres, of which 60 million are federal lands, a uniquely high percentage. This mountainous state has 296 ranges according to Wikipedia. Much of the intermountain land is arid. Subtracting 6.6 million acres in wilderness, 15% of the state could suffice to meet 18% of the nation’s energy needs while treating all of the state’s sewage.Other western states with significant federal land include New Mexico and Arizona, enough to generate half the nation’s energy needs in the western U.S. Producing 3,000 gal per acre of valuable fuel should lure many farmers away from corn. With the vast acreage in the multistate Corn Belt, algae-based biofuels should free us from foreign oil, and they are carbon neutral.

By David A. Schooley
Reno, Nev