Now if you figure out how to make producer gas aka syngas, and have a woodlot, you’ll be all set.
It’s messy and you have to be careful about storing and handling your feedstock but it’s only moderately challenging to convert an old six cylinder truck engine to wood gas. My folks were back to the earth sorts in the seventies and subscribed to Mother Earth News, I recall their wood gas truck plans clearly, smokestack in the bed and all. An acquaintance of theirs with a small sawmill operation actually converted an engine to power his equipment, since he had sawdust coming out his ears and not much else to do with it at that time, lol. It was not uncommon in England during WWII either, but I think they may have used peat.