Their report is published in Natural Resources Research (Vol. 14:1, 65-76).

In terms of energy output compared with energy input for ethanol production, the study found that:

• corn requires 29 percent more fossil energy than the fuel produced;
• switch grass requires 45 percent more fossil energy than the fuel produced; and
• wood biomass requires 57 percent more fossil energy than the fuel produced

In terms of energy output compared with the energy input for biodiesel production, the study found that:

• soybean plants requires 27 percent more fossil energy than the fuel produced, and
• sunflower plants requires 118 percent more fossil energy than the fuel produced.

Click here to read the full article