I had a thought today. Generators use X fuel/hour, no matter how many watts are being used. What if you were to incorporate a battery bank, and have the generator start the engine as needed to top that off or if you need more power, in much the same way a hybrid car uses the batteries to power the wheels and only burns gas as needed.

Does anyone know of anyone who makes something like this? Or should I be getting myself to the patent people after doing some homework?