The steepest challenge faced by every pioneering auto builder was finding a suitable source of power. Petroleum-fueled internal combustion (IC) powerplants, steam engines, and electric motors all energized the drive to replace horses with horsepower. When one contraption lacked the gumption to climb hills, resourceful horseless-carriage constructors simply added a second powerplant as if they were harnessing another mare to the team. Later, we dubbed these concoctions hybrids.
1894: Italian textile manufacturer Count Felix Carli added a box of tensioned rubber bands to double the power available in his electric tricycle.
1897: Justus Entz, chief engineer at a Philadelphia battery company, built the first carriage powered by an IC engine assisted by an electric motor. Sluggish performance was reported. Worse, the experiment was destroyed when a rogue electrical spark ignited the fuel tank.
1899: Two hybrids appeared at the Paris Salon. One from a Belgian firm featured parallel IC and electric propulsion using a system similar to Honda's Integrated Motor Assist. A French design employed a series configuration; here, an IC engine powered a generator which supplied current to two electric motors driving the wheels. In the decade that followed, several other makers touted series hybrids at the Paris Salon.
1900: Like Henry Ford, Ferdinand Porsche's first career stop was in the electrical field. He earned two related patents in 1897: one for a motorized wheel hub, the second for a series-hybrid propulsion system. While employed by Jacob Lohner, Austria's leading vehicle manufacturer, Porsche brought these concepts to fruition. After a front-drive Lohner-Porsche carriage sparked interest at the 1900 Paris Salon, a four-wheel-drive version was built. The latter model's storage battery weighed nearly two tons so Porsche added a pair of generators driven by 2.5-hp Daimler IC engines to extend operating range. What Porsche called "mixte" (mixed) propulsion successfully powered military vehicles, fire-fighting equipment, and Mercedes automobiles.
1902: A series-hybrid runabout constructed by Knight Neftel competed successfully against steam and gas-powered buggies in the New York to Boston Reliability Test.
1915: The Owen Magnetic used a conventional IC engine powering a generator supplying electricity to a drive motor, thereby eliminating gear changes.
1916: Two prominent electric-vehicle makers - Baker of Cleveland, Woods of Chicago - both offered hybrid propulsion. The latter could be driven using gasoline, electric, or both motors. Performance claims for the Woods Dual Power were a top speed of 35 mph and 48 mpg fuel efficiency. Since it cost as much as a Cadillac V-8 with electric starting and twice as much power, few were sold.
1938: GM's Electro-motive Corporation began supplanting steam locomotives with diesel-electric hybrids. A large IC engine driving a generator supplies power to electric motors which drive the engine's wheels. No electrical energy is stored on-board.
1939: Electrogear buses manufactured and operated in Philadelphia used a differential transmission capable of blending IC and electric power for heightened efficiency.
1944: P.M. Heldt's Torque Converters or Transmissions for Use with Combustion Engines in Road and Rail Vehicles, Tractors and Locomotives was published. This handy reference soon became the preferred source of inspiration for hybrid engineers the world over.
1969: GM engineers in England constructed a two-seat minicar with a parallel-hybrid drive, a 35 mph top speed, and a 150-mile range.