I was watching a show the other day on discovery science, and there was a guy with an ethanol-powered mooney. Basically its corn alcohol, and while we don't have enough to replace our oil supply for cars, you would think that the private/personal aviation market would benefit from this fuel due to its cheap cost and the fact that the changes needed to the fuel system are minute. Also, I'm aware that there are a few diesel aircraft soon to be certified, and wonder why biodiesel isn't catching on as well. Like I said previously, making enough for mass transportation probably isn't possible, but for small airports I don't see why these cheap enviro-friendly fuels aren't used more.
http://www.e85fuel.com/index.php
http://www.findarticles.com/p/articl...7/ai_102090258