Better Than Corn? Algae Set to Beat Out Other Biofuel Feedstocks

One acre of algae can produce enough oil to make 5,000 gallons of biodiesel in a year.
Photo by Roth Washburn via Flickr

Forget corn, sugar cane, and even switchgrass. Some experts believe that algae is set to eclipse all other biofuel feedstocks as the cheapest, easiest, and most environmentally friendly way to produce liquid fuel, reports Kiplinger’s Biofuels Market Alert. “It is easy to get excited about algae,” says Worldwatch Institute biofuels expert Raya Widenoja. “It looks like such a promising fuel source, especially if it’s combined with advances in biodiesel processing.”

The inputs for algae are simple: the single-celled organisms only need sunlight, water, and carbon dioxide to grow. They can quadruple in biomass in just one day, and they help remove carbon from the air and nitrogen from wastewater, another environmental benefit. Some types of algae comprise more than 50 percent oil, and an average acre of algae grown today for pharmaceutical industries can produce 5,000 gallons (19,000 liters) of biodiesel each year. By comparison, an average acre of corn produces 420 gallons (1,600 liters) of ethanol per year, and an acre of soybeans yields just 70 gallons (265 liters) of biodiesel per year.

“Your bang for your buck is just bigger because you can really do this on a much smaller amount of land and yet yield much, much higher biomass,” said Michael S. Atkins, CEO of San Francisco area-based Ocean Technology & Environmental Consulting (OTEC). Douglas Henston, CEO of Solix Biofuels, a company that grows algae for biofuels, has estimated that replacing all current U.S. diesel fuel use with algae biodiesel would require using only about one half of 1 percent of the farmland in production today. Algae can also grow on marginal lands, such as in desert areas where the groundwater is saline.

But creating an optimal environment for algae can be difficult—and costly. Open ponds are often host to a wide range of other species, including invasives, and balancing temperature needs, light levels, fluid circulation, and other factors can raise the price tag quickly. According to a recent Worldwatch report on biofuels, in the near term, algae production for fuel is only likely to be economical in cases where the organisms are grown near power plants, where they can also help soak up the pollution. A Massachusetts company, GreenFuel Technologies, is building such systems in Arizona, Louisiana, and Germany, and hopes to capture as much as 80 percent of the carbon dioxide emitted from the plants during daylight hours.

On its Web site, Solix Biofuels notes that rising gas prices are making algae-based biofuel more attractive. With it and other companies now investing in the technology, experts estimate that large-scale commercial production of algae fuel could be just five years away, Kiplinger’s reports.

This story was produced by Eye on Earth, a joint project of the Worldwatch Institute and the blue moon fund. View the complete archive of Eye on Earth stories, or contact Staff Writer Alana Herro at aherro [AT] worldwatch [DOT] org with your questions, comments, and story ideas.