I frequently hear of the clearing of land in far flung places of it's indigeonous flora, fauna and population to make way for corporate monoculture feedstock production, so we can pat ourselves on the back for being so 'green' and providing the 'developing' world a magnificent business opportunity...
Anyway, I came across this, which I found encouraging:
http://bloomingfutures.com/PPO is the lowest impact road fuel available today it has a footprint far smaller than both conventional diesel and bio-diesel.
PPO is estimated as having an energy fotprint over 25 times smaller than its chemically procesed cousin bio-diesel and a footprint well over 50 times smaller than bio-ethanol.
They're a workers co-op, too!