Biodiesel returns more energy than ever: study

Oct. 16, 2009
Biodiesel is better than ever at harnessing the power of the sun and turning it into fuel

Biodiesel is better than ever at harnessing the power of the sun and turning it into fuel. In fact, a study shows the fuel is returning more than four times the energy that it takes to make biodiesel.

Newly published research from the University of Idaho and US Department of Agriculture shows that for every unit of fossil energy needed to produce biodiesel, the return is 4.5 units of energy. This energy-in, energy-out ratio is “energy balance.” Biodiesel made from soybean oil has a high energy balance because the main energy source used to grow soybeans is solar.

“This gives Americans even more reason to put their faith in the environmental and societal benefits of biodiesel,” said Joe Jobe, chief executive officer of the National Biodiesel Board. “The Environmental Protection Agency should take this into account when considering biodiesel’s greenhouse gas reductions,” he said.

Jobe was referring to EPA’s proposed rule to implement the expanded Renewable Fuels Standard (RFS2). EPA used 2005 baseline numbers for petroleum and biodiesel to project carbon impact 22 years in the future. That stacks the deck in favor of petroleum.

“In its rulemaking, EPA should recognize that biodiesel production is growing more efficient, while oil exploration and drilling becomes more intensive each day,” Jobe said.

The USDA/Idaho study finds key drivers that continue to make biodiesel an efficient fuel choice:

  • New seed varieties and management practices are upping soybean yields.
  • Farmers have minimized cultivation of the soil. These reduced tillage practices have cut how much fuel they need to grow soybeans.
  • Modern soybean varieties have reduced the need for pesticides.
  • Today’s soybean processing and biodiesel plants are more energy-efficient.
The new study is based on biodiesel produced from soybean oil, the largest share of the biodiesel market. Other abundant sources used for biodiesel included recycled cooking oil, fats, and other plant oils such as canola oil.

For more details on biodiesel and NBB’s formal comments to EPA, visit For a complete copy of the report, go to and click on Papers and Reports.