Much discussion there about biodiesel vs ethanol versus other liquid fuels.  This was a lipid conference so many more details about biodiesel from vegetable sources.  First some details from a talk by Frank Gunstone from St. Andrews University.

As of 2005 There was a total of 135 million metric tons of lipids cycled through.  These are from Fish, animal and vegetable sources.  Animals are via rendering and is becoming a smaller % each year.  OF that 135 M metric tons about 80% went to food, 14% to oleochemistry and 6% to feed and other.  By 2020 these numbers may have to increase by 40% just to keep up with population growth.

A significant chunk of those lipids and fats are part of a food stream, not dedicated lipid production.  There is significant potential to increase lipid production by planting more oil seed crops.  A lot of comes from corn but it is a poor oil producer (<6% oil typically in grain) compared to something like an oil palm.  Really 2 sources accounted for the fast majority of oil seed lipids in 2005, soybeans and oil palms.  2005 was the first year that palm oil was greater than soy oil.  

That growth in palm oil is really critical because oil production for palms is up to 5 tons per acre per year while soy beans are less than one ton.  There can be an increase in non food grade lipids much faster than lipids from food sources would indicate.

Lastly for today.  A talk on biodiesel showed that the EROEI for biodiesel from bare ground to in the tank is 3.2-1. I believe this is for soybeans in the U.S. Very positive and much better than ethanol.  The biodiesel numbers include fertilizer and all input costs.  

More later on this conference when I have time.