Nicholas Otto used ethanol to power his "Ottocycle," creating the prototype for today’s internal-combustion engine.

Interest in the steam engine sidelined the work Morey did with internal combustion for 35 years, until German inventor Nicholas Otto began his research, eventually developing a four-stroke internal-combustion engine. With thousands of small ethanol distilleries across the U.S. producing more than 90 million gallons per year (MGY), ethanol was the natural choice to fuel his engine, which he later used to power a motorcycle.