Abstract: A system for supplying power with a combustion engine includes an engine having fuel and air intake lines, and an exhaust line. The engine has a combustion chamber volume defining a number of liters of engine displacement. A fuel cell has a gas outlet that communicates with the air intake line, and selectively produces hydrogen and oxygen gases through an electrolysis process. An oil pressure sensor communicates with the engine to sense when the engine is operating. A switch communicates with the sensor and is closed when the sensor senses that the engine is operating. The switch is open when the sensor senses that the engine is not operating. A battery communicates with the fuel cell and selectively supplies electrical power for the electrolysis process when the switch is closed.