can you convert a propane fridge to run off of a biogas generator yes absolutely that’s why I’m a fan of ammonia gas refrigerators people typically run them off of propane because it’s cheap and convenient but an absorption refrigerator just needs some sort of fuel it just needs some sort of heat this can be propane this can be natural gas it could even be electricity but it can also run off things like kerosene or an oil lamp or yes even biogas and the cool thing about biogas is it’s really easy to produce yourself you’re not going to heat your home with this but you can produce enough gas to cook and maybe even refrigerate your food that said biogas is nowhere near as energy dense as propane so you will need to make some modifications to your fridge and then there’s the fact that propane is dirt cheap and really convenient so until the world falls apart running a propane fridge off of a biogas generator isn’t really practical but once the world does fall apart you’ll be glad that you have this option