ho hum, where angels fear to tread.................

It's totally missing several points - our biggest problem is not dependance on mineral oil, that is just one symptom of many of the big problem, which is overpopulation.......... If you just simplistically replace mineral oil with "grown" oil, you just exascerbate a whole raft of other problems - ultimately, whatever the fuel, it's still "burning stuff" which will contribute to mankind's demise on earth.
We have what used to be a beautiful planet - IF we grasp the nettle of overpopulation swiftly, and realise that "less really is more" there may be a chance of saving mankind - I fear biodiesel is just another blind alley or diversion whilst mankind's time left on earth shortens...
