Any one out there run BD? I've made a few "test" batches. If SHTF or TEOTWAWKI, a field of soybeans = diesel power. Only item I could see as being hard to come by would be the caustic (sodium hydroxide) you can brew the methanol and press the oilseeds.
I have a problem (for lack of a better word) with bio-diesel. If you're going to use food for fuel (corn, soy, whatever) then who gets the last morsel at the end of the day? The hungry people or their hungry cars? I'm not saying that we don't need to have fuel alternatives - because I look forward to any useful fossil fuel replacement - but I really wonder what the end result of food-as-fuel will be.
market would say what ever pays more will get the last bushel.So food prices go up to keep pace with fuel...( ooh definitely not a good thing.)
Instead of using food for fuel, I will build a wood-gas generator, then convert the gas in a Fischer Tropsch reactor. This is the method that Nazi Germany used to convert coal to liquid fuel
A rather extreme method, but if the folks that run cows put on diapers (like the horse carriages in Central Park) and put the contents in a digester, we'll have a slew of methane. This scheme has been done a bit with cow barn cleaning. The resulting liquid is pretty good fertilizer, oddly enough called "liquid fertilizer." A mite obvious when it is spread on the fields, but it is real recycling in action. The cases I know about have been fairly few, and the methane was wasted in burners; the goal is stabilized material that is a pretty decent soil amendment. Sewage treatment plants often use digester gas for fuel to generate electricity on site, it reduces the electrical demand on the local utility company.
But you can press oil seeds , saving the food part and then process the oil for fuel. That's how they make defatted soy flakes organically, otherwise they defat them with hexane. Yeah probably not too efficient in a SHTF situ. maybe teotwawki though.
