TCS Daily

Hybrid History

By Ralph Kinney Bennett - January 19, 2005 12:00 AM

The hybrid cars being touted at the big auto shows by Toyota, Honda and Ford, and the ones contemplated by GM and Daimler-Chrysler are the culmination of more than a century of dreams and experiments regarding "mixed propulsion" for automobiles.

Attempts to combine internal combustion engines (ICE) and electric power date back at least to 1897, evidence that, conceptually speaking, there is little really new under the automotive sun.

In 1900, a Belgian maker, Pieper, introduced a 3-1/2 horsepower "voiturette" in which the small gasoline engine was mated to an electric motor under the seat. When the car was "cruising," its electric motor was in effect a generator, recharging the batteries. But when the car was climbing a grade, the electric motor, mounted coaxially with the gas engine, gave it a boost. It was a crude but uncanny anticipation of the new Honda hybrid's "integrated motor assist" (IMA) system.

A Belgian firm, Auto-Mixte, built commercial vehicles using the Pieper patents between 1906 and 1912. A French maker, Krieger, built several large cars combining both alcohol and gasoline engines with electric motors and even patented a gas-turbine/electric system in 1908, shortly before going into bankruptcy.

None of these vehicles proved reliable over the long run, and it fell to a brilliant young Austrian engineer named Ferdinand Porsche to take the next step.

Porsche 'mixtes' it up

Hired by an Austrian carmaker, Jacob Lohner, Porsche at first developed a then-sensational system whereby two electric motors, attached directly to the front wheels, powered the car.

These very fast "Lohner-Porsches" won many auto races. But their practical use was hampered by the same shortcomings that have haunted pure electric cars to this day - batteries that weighed too much and stored too little electricity, restricting cruising range.

Porsche solved that problem, with his own mixte system, "mixing" an internal combustion engine with electric motors that improved on the scheme of the Krieger cars. His solution was elegant - the internal combustion engine (ICE) powered a dynamo, which sent its current directly to the electric motors at the car's wheels. The driveshaft was eliminated.

The cars were sensational performers and the young Porsche loved to race them. He soon built a Lohner mixte with electric motors on all four wheels. These cars achieved speeds of 70 miles an hour, which in 1903 was a more than head-turning speed.

Porsche's success (he was still in his 20s) attracted the attention of Daimler Motors, which bought the patents and hired him in 1906. Austro-Daimler produced his famous Mercedes-Electrique-Mixte, some models of which Porsche drove in races.

Other European makers and a few American were inspired to try their own versions of mixed propulsion. One of the most notable was the Woods Dual Power, made in Chicago by a firm then known for its electric cars. Introduced in 1917, it incorporated a four-cylinder Continental engine mated to an electric motor. With both motors running, its top speed was a sedate 35 miles an hour. That may not seem much, but it was a pretty good speed for most four-cylinder cars of the day and it was attained with much less noise and vibration than in other makes.

Porsche's system was employed on some German military vehicles during World Wars I and II. But it was too expensive to be cost-effective in civilian use as gasoline engines and their transmissions improved. The various mixed systems were plagued by problems of coordination between the two power sources. Like electric and steam propulsion, they fell by the wayside as the ICE became increasingly smooth, reliable and powerful. And gasoline, a refining by-product that oil companies had once burned off or thrown away as useless, was cheap and abundant.

Post War Experiments

Two post World War II American efforts at hybrid power are worth noting, although tantalizingly little is known about them. In 1948 Beech Aircraft Co., of Wichita, Kans., announced plans to build a large and expensive sedan called the Beechcraft Plainsman. A striking prototype featured a four-cylinder air-cooled Franklin engine coupled to an electric generator that sent juice to four electric motors mounted at each wheel -- a set-up schematically similar to Porsche's old mixte system.

The Plainsman, with its sweeping aluminum body and huge expanses of glass, was a lavish and very modern-looking six-passenger car, even featuring an air suspension. The projected price was a hefty $5000, about the same as a Cadillac limousine at the time. But as Cold War military contracts began ramping up, Beech concentrated on its aviation business and the car never went into production.

The Electronic La Saetta, announced in Salt Lake City in 1955 by the Electronic Motor Car Corp., was a two-seater fiberglass-bodied sports car. It featured an 80-cell battery pack that was to be constantly recharged by either a gasoline or diesel "turbogenerator." Battery power was then transmitted to a "Dual-Torque" electric motor inside the rear axle housing. This fascinating car never went into production.

It remained for Honda, with its Insight, and Toyota, with its Prius, to bring the term "hybrid car" into popular usage and put mixed propulsion back in the spotlight.

The 'New' Hybrids

I tested both the Insight and Prius for The Reader's Digest back in 2001. Both cars impressed me far more than I had expected. I found the Prius particularly comfortable, versatile and very much like a good "normal" small car in driving and handling. But it was a bit homely and had an "almost but not quite" quality about it.

Since then Toyota has gone from almost to way past quite.

The new Prius has a five-door hatchback body with a sort of "subdued ultratech" look to it that is a little less homely looking. The car is bigger (an inch shorter than Toyota's full-size Avalon), roomier and more powerful than its predecessor. In the hands of a seasoned hybrid driver it can achieve 60 miles per gallon in city driving. And the whole package has fabled Toyota build quality.

Without getting into technical details, the Prius is a rolling clinic on what can happen when advances in know-how and materials catch up with elegant ideas and daring dreams. The small, powerful, reliable electric motors designed and built today are a far cry from the wheel motors on Porsche's mixte cars, which weighed almost 250 pounds each. And early 20th Century engineers could not conceive of the role advanced electronics and microprocessors would play in managing, monitoring and switching power between the ICE and the electric motor.

This latter is the real key to Prius' genius. The average driver behind the wheel of this car, would have not the slightest idea that while moving his foot from brake to gas pedal and back he is commanding a sophisticated and complex interaction between the gas and electric motors.

Although I have not driven the new Accord Hybrid, tests I have read indicate this same smoothness of operation. It is this precise and subtle management of the gas/electric power - flawless and undetectable to the driver - that eluded earlier engineers and designers.

The fascinating advances modern engineers and designers are now making in hybrid propulsion systems may extend the role of fossil fuels in automobiles far beyond what anyone has imagined. But the trail was blazed long ago, by the forgotten engineers at Pieper, the brilliant Dr. Porsche and other visionaries of "mixed propulsion."


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