Did some checking, and while the coal dealer on the other side of the river has closed, there is a propane dealer in this county that sells coal...all kinds of coal, hard and soft, bagged or bulk, and they deliver!
Wood gas is as old as the second world war, I knew an old German that served the Nazi and was a driver he said wood gas was a common resource seeing gasoline was hard to get. In the 1960s some boys drove from California to /Florida on wood gas. Basically the wood is not allowed to burn but smolder and be drawn through a water tank as a filter. the vacuum on the intake of the engine draws the gas off. Initially one is started with gasoline first to get the vacuum started. It would be novel to run a generator on wood gas, if a one cylinder engine can produce enough draw off the water filter. Most newer engines have satellite valve seats to tolerate the heat, but that's no guarantee the valves themselves can take it.