Scientific American, in the August 2011 issue, features an article entitled “Biofuels’ False Promise.” It does quite a good job of summarizing the reasons biofuels of all sorts have not come close to delivering on the hopes that have been invested in them, and possibly never will.

Those hopes were raised by the idea we might be able to avoid putting fossil carbon back into the atmosphere by running our vehicles on biofuels. They were raised higher by the added prospect of possibly lowering the demand for fuels made from oil, thus becoming less dependent on the world oil market and also lowering the price of the oil we do buy. None of this has happened. The article by David Biello, an associate editor at the magazine, explains why.

First, we might look at the time and money that has gone into the effort to create biofuels. “Despite the best hopes of scientists, CEOs and government policy makers, hundreds of millions of dollars in government money, more than two dozen U.S. start-ups financed by venture capital and decades of concentrated work, no biofuel that can compete on price and performance with gasoline is yet on the horizon,” says Mr. Biello.

The most developed biofuel, ethanol made from corn, is examined first. The United States produced 13 billion gallons in 2010, mostly used in a mixture with gasoline. Unfortunately, corn-based “Ethanol yields little if any net savings in carbon dioxide emissions,” the article mentions, and goes on to point out other flaws:  To make that much ethanol used up 40% of the corn crop, contributing to increased food prices and, in fertilizer runoff, also contributing to the Gulf of Mexico “dead zone.”

Biofuel made from non-food plants – the much promoted “cellulosic ethanol” – was supposed to overcome some of these flaws. However, “Lots of energy is required to distill ethanol from the soup of water and yeast in which it has been fermented, energy typically supplied by burning fossil fuels.” That’s true whether the feedstock is corn or wood or any other biomass. For this and other reasons, the article points out, “None of these advanced biofuels is working at commercially meaningful scales today.”

The scale at which the United States consumes gasoline and diesel fuel made from oil is an essentially impossible obstacle to a plan to run our society on biofuels. The Congressional Research Service says, “… if the entire record U.S. corn crop of 2009 was used to make ethanol, it would replace only 18% of the country’s gasoline consumption.” Another way to understand this scale is a calculation made by J. Craig Venter, co-founder of Synthetic Genomics, a would-be biofuel producer:  “Replacing all U.S. transportation fuels with corn ethanol … would require a farm three times the size of the continental U.S.”

Much of the article is taken up with speculation about the possibility that genetically engineered organisims, either some kind of modified algae or an entirely artificial form of life, can be made to produce biofuels. Among the obstacles mentioned is the fact that nutrients other than water and sunlight would be needed for any possible variation on this theme to work. In any case, there is as yet no process sufficiently worked out that its practicality can be evaluated. We will not be running on this sort of biofuel for the foreseeable future.

Neil Renninger, chief technology officer for Amyris, a California company experimenting with the production of hydrocarbons with a much higher value than oil, is one of many experts who argue our expectations for biofuels should be lowered. The article says, “All the energy in crops grown today – along with plants consumed by livestock and trees harvested for pulp, paper and other wood products – comes to roughly 180 exajoules, or about 20% of world energy consumption.” Of course, using that primary biological production for fuel would mean not using any of it for food.

The article concludes with a quote from ecologist G. David Tillman of the University of Minnesota. ‘We can all live with different kinds of transportation,” he says. “We can’t live without food.” It’s a pretty sound reason to give up on the idea of running our cars with biofuels, and to think about how we might be able to live without running them at all.

I had hoped to provide a link to the article. Scientific American does not work that way. To read the original Scientific American article, you will need to become a “digital subscriber” to the magazine, or an old-fashioned analog subscriber, or go to your local library.

Art Myatt

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