I used to be super interested in biofuels and making sustainable supply for myself.
I read the books. Studies which crops produce the highest yields in my part of the world.
Alcohol takes a lot of effort to make and it’s not very efficient compared to a Diesel engine. You have to make alcohol to produce biodiesel and to drink because in a world where you have to make your own gas, your gonna need to get yourself drunk too.
A modified diesel vehicle that can run straight vegetable oil is the best setup. For ease of use. In cars, they seem to burn dirty and crud stuff up. Ruining the engine. On a moped (converted to a Diesel engine),you could pull it apart and clean it out to prevent damage from “coking”.
If you lived in oil palm and sugar cane growing zoned you would be all set. In the majority of the US, I would think corn would be good for oil and ethanol.
All that said, I figure the work to make the moped run is way harder than just riding a bike
I really got into Dean Kamen’s Engineering later on. He makes some interesting stuff with Sterling Engines. They aren’t just novelty engines. They can power stuff. You could burn anything flammable to create heat for it to run. My dream is to someday build a sterling engine motorcycle that doesn’t suck.
On this topic, don’t forget to google the old Wood gas generator.
As far as just pour it in and go, like said above, you could probably mix pure ethanol and kerosene in a proportion that gets you going without too much trouble. (edited)