This is something I beat to death for several years. Finally I figured out I would learn to use alternate fuels for a internal combustion type engine. Still will be using solar and wind but some days you need an engine.
I will use small engines fired with gas from burning wood. This url will take you to a website of a person that is making his own “gasifiers.”
You can build your own from about anything (from boilers/hot water tanks to fire extinguishers) but is a try and