That is why a second group of scientists—including J. Craig Venter, the entrepreneur and biologist whose Institute for Genomic Research in Rockville, Md., played a key role in mapping the human genome—argues for a bolder approach. These researchers believe that the best biofuels will bypass crop plants—cutting out the middleman entirely—relying instead on algae and a few microorganisms that have a plantlike knack for directly and efficiently turning sunlight into energy through photosynthesis. The scheme has yet to be proved on a large scale, however. “I haven’t seen anyone really do a fair calculation of what algae can do,” Keasling notes, “and until I see that, I’m not convinced.”

Regardless of the method, scientists will have to improve on Mother Nature to make a successful biofuel, tinkering with existing microorganisms or even building brand-new ones. Dozens of start-ups are manufacturing fuels from novel strains of yeast, algae and bacteria. Several promise that by 2011 they’ll have made gasoline or diesel substitutes that can be pumped directly into cars. And although these biofuels will probably first be supplied preblended with traditional gasoline or diesel—much the way E10 is today—one day we may use them alone and say good-bye to petroleum-based gasoline forever.

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