Corn or Soy? Neither

When it comes to biofuels, which crop wins? Corn (for ethanol) or soybeans (for biodiesel)? Based on the findings of a new study to be published in The Proceedings of the National Academy of Sciences, the New York Times reports that research,

...points to the environmental benefits of the biodiesel over ethanol made from corn, stating that ethanol provides 25 percent more energy a gallon than is required for its production, while soybean biodiesel generates 93 percent more energy.

The study’s authors also found that ethanol, in its production and consumption, reduces greenhouse gas emissions by 12 percent, compared with fossil fuels. Biodiesel, they said, reduces such emissions 41 percent, compared with fossil fuels.

However, neither crop would appear to be the answer. As the article notes:

...neither ethanol nor biodiesel can replace much petroleum without having an impact on food supply. If all American corn and soybean production were dedicated to biofuels, that fuel would replace only 12 percent of gas demand and 6 percent of diesel demand, the study notes.

According to the Times,

The study concludes that the future of replacing oil and gas lies with cellulosic ethanol produced from low-cost materials like switch grass or wheat straw, if it is grown on agriculturally marginal land or from waste plant material.