Speaking of waste products.
gasoline was originally considered a waste product of the petroleum industry. When Edwin Drake drilled the first crude oil well in Pennsylvania in 1859, his goal was to produce kerosene for lighting, not gasoline. The gasoline produced as a byproduct was often discarded, burned at the refinery, or used as a gaseous fuel for gas lights. However, in 1892, the invention of the automobile led to the recognition of gasoline as a valuable fuel. By the early 20th century, gasoline was widely used as an important source of energy because gas engines were more efficient and powerful than early electric motors.