Looks like everyone going fast on furious on this may more so than the oil companies, Lakeland Florida was playing with running their buses on treated veggie oil that came from frying french fries etc. as a matter of fact the exhaust did smell like french frys or pretty close The problem I see here is the demand exceeding the available "feed stock" to do it There is a tree in South America
that the sap when tapped will run diesel engines (some sort of Pine?? like Turp??) urban legend? , Also there was a neat magazine that came out a few months ago called diesel power by the same publisher as 4 wheeler saw 4 issues now cannot find it , It of course was devoted the hopping up truck diesels and engine swaps but they did have a page on whats happening in the diesel world
.Olive oil also costs bucks we use it for cooking (heathy) but $5 for about 6 or 8oz Corn or safflower costs a lot less, a biodiesel mix maybe 70/30 petro source/corn oil may be where its headed at least a start to the green planet thing martin