There are companies like Westinghouse and WEN making powerful, lighter, quieter, and efficient generators, but the most powerful one is Briggs & Stratton’s 30795 P4500 which has a 4-stroke engine, 4000 watts power, and 3.5 gallons tank volume. You can run this machine for straight 16 hours at 25% load. The perfect partner for your RV and campsite.