Biodiesel pumpResearchers from the University of Idaho and the U.S. Department of Agriculture (USDA) have analyzed the energy life cycle of soybean-based biodiesel and presented updated data showing the renewable fuel offers a fossil energy ratio of 5.54 to 1. This isn't a typo. The 5.54:1 ratio comes mostly from the "free" power of the sun that helps the crops grow.

This energy-in, energy-out ratio – commonly referred to as energy balance – shows that "biodiesel production continues to improve when it comes to efficient use of resources," according to Don Scott, director of sustainability at the National Biodiesel Board. Furthermore, Scott claims that, "No other fuel available in the U.S. comes close to such a high energy balance."

Since the USDA had to conduct its analysis using data from 2006, it's quite likely that biodiesel production techniques have improved significantly in five years' time. Why? Well, there seems to be a trend in biodiesel production efficiency. The U.S. Department of Energy (DOE) and USDA completed a comprehensive life cycle assessment for biodiesel back in 1998. That study found a 3.2:1 energy balance. Then, in 2009, the DOE and USDA revisited biodiesel production and, using data from 2002, found the ratio had soared to 4.56:1. Jim Duffield, USDA senior agricultural economist, who co-authored all three biodiesel life cycle analysis, says that:
In addition to improved energy efficiency at processing facilities, soybean growers have accomplished greater yields with lower inputs of water and fertilizer per bushel, even as cropland has declined.
And the Western Farm Press boldly claims that biodiesel is the "only commercially available, advanced biofuel" made in the U.S.A. Apparently, standard corn ethanol isn't considered "advanced," then?

[Source: Western Farm Press | Image: jsbarrie – C.C. License 2.0]