Outboard motor
An outboard motor is traditionally an engine that is used with boats. With those is no need for oars. An outboard motor can be an electric motor, which doesn't pollute at all.
Outboard Motor Media
1979 Evinrude 70 hp outboard, cowling and air silencer removed, exposing its shift/throttle/spark advance linkages, flywheel, and three carburetors