The generator upgrade allows devices to re-fuel on the go. Currently it only supports solid fuels, such as coal. It has an internal inventory that can store one item stack of fuel. Surplus fuel can be removed from the generator using the appropriate component API method. When removing a generator upgrade from a robot, its contents will be dropped into the world.
The efficiency of generators is lower than that of usual generators from other mods, meaning it is usually more fuel efficient to power devices using a charger.