The name Porsche
has been associated with pioneering automotive engineering innovations
since the beginning of the last century. In 1900 Prof. Ferdinand Porsche
unveiled his Lohner Porsche, an electric car with wheel-hub motors
driving the front wheels. Soon after, this car featured all-wheel drive
and four-wheel brakes, another world first. A highlight of his early
years as an automotive designer was the Lohner-Porsche Semper Vivus that
went down in history 111 years ago as the first functional hybrid car.
Porsche’s Semper Vivus (Always Alive) recreation is a tribute to Prof. Porsche’s visionary invention. The fully functional Semper Vivus replica, based on original drawings and exhaustive research, is a collaborative effort between Porsche Engineering and Karosseriebau Drescher, a coachbuilding company based in Hinterzarten in the state of Baden-Württemberg, Germany. This faithful replica, whose visionary design impresses to this very day, is on display at the New York Auto Show press day on April 20.
Prof. Porsche had entered uncharted territory with the Semper Vivus, the world’s first functional, full-hybrid car. In this vehicle, two generators paired with petrol engines formed a single charging unit, simultaneously supplying electricity to wheel-hub motors and batteries. In autumn 1900, Prof. Porsche set to work on a first prototype with petrol-electric hybrid drive. Presumably he based the world’s full hybrid car on a conversion of his electric racing vehicle from the Semmering-Bergrennen race. To this end he combined his electrical wheel-hub motors with two combustion engines and no mechanical connection whatsoever to a drive axle. Instead, they each drove an electric generator supplying both the wheel-hub motors and accumulators with electricity. This was the birth of serial hybrid drive. As a full hybrid concept, the Semper Vivus was also able to cover longer distances purely on battery power until the combustion engine had to be engaged to recharge the batteries.
In practice, Prof. Porsche still had to contend with the principal
problem of his wheel-hub cars –the vehicle’s heavy weight. Although the
Semper Vivus hybrid car’s total weight was only 70 kg more than the
original version, the 1,200 kg prototype was a challenge for the
pneumatic tires’ soft rubber mix. In other respects as well the hybrid
concept was still a long way away from being ready for series
production. With its bodiless chassis, exposed petrol engines and
unsprung rear axle, the Semper Vivus may have impressed visitors to the
Paris Motor Show in 1901 but potential car buyers must have felt the
bare-bones prototype was not for them. The interaction of engine,
batteries and control system also still needed a lot of development and
in addition to the ambitious control technology, a constant problem was
dirt being thrown up and fouling of the accumulators. Yet the hybrid
concept pointed to new possibilities that Prof. Porsche resolutely set
about turning into reality.
At about the same time, Prof. Porsche again significantly modified
his cars’ drive concepts. For the weight reasons and to reduce
production costs he dispensed with the purely electric driving
capability and shrunk the battery to a minimum for initiating the
starter motor. He replaced the missing energy storage unit with another
innovation. The generator, designed as a stationary armature machine,
was fitted with an electro-mechanical speed regulator patented as a
“device for automatically regulating electric generators.” Prof. Porsche
also ushered in a further development in wheel-hub motor technology. A
redesigned hub casing allowed the kingpins to be relocated closer to the
center of the wheel. This steering geometry, patented in May 1902,
significantly reduced the effect of road impacts and the effort needed
to turn the steering wheel. To reduce the unsprung mass of the wheels,
Prof. Porsche also reduced the diameter of his wheel-hub motors, which
he compensated for by using wider windings.
Despite these impressive demonstrations, sales of the Mixte
production variants remained far lower than expectations. With only 11
hybrid cars sold, the return on investment was not on par with the
enormous technical development costs between 1900 and 1905. The main
problem was undoubtedly the high sales price. Depending on design and
equipment, a Lohner-Porsche Mixte cost between 14,400 and 34,028 Krone,
in some cases making it almost twice as expensive as comparable,
conventionally powered motor vehicles. This was compounded by the high
maintenance cost of the complex drive system that was unable to keep
pace with the ever increasing reliability of normal petrol cars. Pure
electric vehicles, however, were economically more successful.
Approximately 65 Lohner-Porsche electric cars were sold during the first
five years of series production to the end of 1905.
Exhaustive research in various archives the across Europe was the
first step. The outcome was a handful of black-and-white photos and an
original technical drawing serving as the project’s foundation. As with
Prof. Porsche, the Semper Vivus replica initially began as a blank sheet
of paper. This meant that in addition to a good deal of imagination,
the project required extensive research and calculations in order to be
faithfully recreate an accurate and working likeness of the electric
wheel-hub motor. Since no specifications or other helpful records had
survived, experts initially created ready reckoners and design drawings
on graph paper in the time-honored fashion. This involved the
painstaking study and laborious measurement of photos and drawings. As
there was no functioning wheel hub motor in existence, technical details
such as performance and range had to be resurrected and calculated from
scratch.
Today, Prof. Ferdinand Porsche’s innovative spirit lives on at
Porsche AG’s Research and Development Center in Weissach, Germany where
the company is applying its engineering strength to develop various
hybrid systems. Porsche’s first production hybrid, the 2011 Cayenne S
Hybrid SUV, is on sale in many markets including the United States. Its
parallel full hybrid system will be adapted for use in the Panamera S
Hybrid that goes on sale later this year with a U.S. MSRP of $95,000
(excluding destination). Porsche engineers are busy developing its 911
GT3 R Hybrid racecar for further competition while continuing work on
the 918 Spyder plug-in hybrid super sports car the company first showed
at the Geneva Auto Show in 2010.
Output: 2.5 hp (1.85 kW) per cylinder
Electric motor output: 2.7 hp (2 kW) per wheel
Top speed: 35 km/h (22 mph)
Range: 200 km (124 miles)
Overall width: 1,880 mm
Overall length: 3,390 mm
Overall height: 1,850 mm
Total weight:: 1.7 tons
Front wheel weight (single): 272 kg (with wheel hub motor)
Track width front: 1,350 mm
Track width rear: 1,540 mm
Wheelbase: 2,310 mm
Ground clearance: 250 mm
Porsche’s Semper Vivus (Always Alive) recreation is a tribute to Prof. Porsche’s visionary invention. The fully functional Semper Vivus replica, based on original drawings and exhaustive research, is a collaborative effort between Porsche Engineering and Karosseriebau Drescher, a coachbuilding company based in Hinterzarten in the state of Baden-Württemberg, Germany. This faithful replica, whose visionary design impresses to this very day, is on display at the New York Auto Show press day on April 20.
The history of the Lohner-Porsche Semper Vivus
Prof. Ferdinand Porsche was busy designing and developing his cars as early as 1896. The first fruit of his endeavors was an electric vehicle known as the Lohner-Porsche. It was driven by steered wheel-hub motors, and it caused a sensation at the Paris World Exhibition in 1900. This was soon followed by an even more impressive example of Prof. Porsche innovative spirit. A racing car boasting four wheel-hub electric motors became the world’s first all-wheel drive passenger car and marked the automotive engineering debut of four-wheel brakes. No less visionary was Prof. Porsche’s next idea; in 1900 he combined his battery-powered wheel hub drive with a petrol engine, thus creating the serial hybrid drive principle.Prof. Porsche had entered uncharted territory with the Semper Vivus, the world’s first functional, full-hybrid car. In this vehicle, two generators paired with petrol engines formed a single charging unit, simultaneously supplying electricity to wheel-hub motors and batteries. In autumn 1900, Prof. Porsche set to work on a first prototype with petrol-electric hybrid drive. Presumably he based the world’s full hybrid car on a conversion of his electric racing vehicle from the Semmering-Bergrennen race. To this end he combined his electrical wheel-hub motors with two combustion engines and no mechanical connection whatsoever to a drive axle. Instead, they each drove an electric generator supplying both the wheel-hub motors and accumulators with electricity. This was the birth of serial hybrid drive. As a full hybrid concept, the Semper Vivus was also able to cover longer distances purely on battery power until the combustion engine had to be engaged to recharge the batteries.
To save weight and create room for a petrol engine, Prof. Porsche
swapped the original 74-cell accumulator in his electromobiles for a
smaller battery with only 44 cells. In the middle of the vehicle he
installed two water-cooled 3.5 PS (2.6 kW) DeDion Bouton petrol engines –
driving two generators to create electricity –each producing 2.5 hp
(1.84 kW). Both engines operated independently, each delivering 20
amperes with a voltage of 90 volts. The electricity generated by the
dynamos initially flowed to the wheel-hub motors, with the surplus power
being sent on to the batteries. An added bonus was that it was also
possible to use the generators as electric starter motors for the petrol
engines by reversing the direction of rotation.
The road to the Lohner-Porsche Mixte
In 1901 Prof. Porsche developed the revised concept of his
‘petrol-electric hybrid car’ into a variant that was ready for series
production under the Lohner-Porsche Mixte name (borrowing the French
term ‘voitures mixtes’). With a four-cylinder, front-mounted engine,
this model mirrored the Mercedes vehicle concept just recently designed
by Wilhelm Maybach but with its two wheel-hub motors still conforming to
the concept of a serial hybrid car. Prof. Porsche was now using a
powerful 5.5-liter, 25-hp (18 kW) four-cylinder engine from the Austrian
Daimler engine company as an electrical generator. The engine was
connected by a driveshaft to the electric generator located under the
seat, with control handled by a primary controller next to the steering
wheel.
To solve his vehicles’ weight problems, Prof. Porsche was
constantly reducing battery size while also attempting to design a
dust-proof battery housing. While the Lohner-Porsche Mixte was only able
to drive a few kilometers on electric power alone because of the
reduced battery capacity, the unladen weight of the four-seat touring
car including body fell to around 1,200 kg. In normal driving mode the
petrol engine and generator ran at a constant speed, feeding the
wheel-hub motors and battery with electricity at a constant voltage. In
addition to his drive concept’s high-level of efficiency, the car
offered other advantages as well. By reversing the polarity, the
generator could be used as an electric starter motor, eliminating the
need for the strenuous and hazardous hand cranking of the engine.
Before the end of 1901, Ludwig Lohner and Prof. Ferdinand Porsche
had pulled off a respectable result by selling five Lohner-Porsche Mixte
cars. With a selling price of approximately 14,000 Krone each, this
made the cars very exclusive commodities. The purchaser of this initial
series was Emil Jellinek, the well-known general agent of the Daimler
engine company in Stuttgart-Untertürkheim and the inspiration behind the
first Mercedes (named after his daughter) only the year before. Despite
this contact, a cooperation agreement to supply Mercedes engines failed
to materialize and only seven Lohner-Porsches with Daimler engines were
built. From 1903 onwards, petrol engines from Panhard & Levassor
were used because the large French automotive manufacturer had acquired
the license rights for France, Great Britain and Italy from Ludwig
Lohner.
In April 1902, having incorporated these improvements, Prof.
Porsche took his place on the starting grid for the Exelberg race. His
two-seat Mixte racing car was not only visually impressive due to its
modern proportions but impressive on the track, as well. His
Lohner-Porsche seemed to cope effortlessly with even the steepest
gradients of the 4.2-km gravel road leading up to the Exelberg, and it
emerged as the victor in the large car class. Porsche received
additional high-profile publicity in the autumn of 1902 when he
chauffeured Austrian Archduke Franz Ferdinand in the Lohner-Porsche
during a military maneuver. The aristocratic passenger seems to have
liked the vehicle with its elegant touring body. Soon after, Prof.
Porsche received a thank you letter testifying “just how satisfied in
every respect his Imperial Majesty” was after the ride.
The reincarnation of the Semper Vivus
In November 2007 the Porsche Museum embarked on one of the most
interesting and challenging projects in its history: the construction of
a faithful replica of the 1900 Lohner-Porsche Semper Vivus. Even 111
years after its invention, building the world’s first functioning hybrid
car was a great challenge for all. Ultimately it was not just about an
extreme attention to visual details but also achieving the same
performance as the original. The Porsche Museum entrusted the
workmanship to a team of experts led by coachbuilder Hubert Drescher,
who had already proven his competence in numerous difficult restoration
projects. As with a number of racing car projects, the aluminum body of
the Porsche Type 64 museum exhibit originates from the Hinterzarten
coachbuilder workshop, as well.
When it came to selecting materials, coachbuilder Drescher took his
inspiration, among other sources, from coaches and carriages from the
dawn of the 20th Century. This required the assistance of experienced
suppliers who were entrusted with the manufacturing of the special
materials. The fully functioning Semper Vivus replica, which took
approximately three years to build, does not solely include replica
components. For example, it was possible to fit some original components
including combustion engines.
Semper Vivus Facts and Figures
Engine: 2x Single cylinder De-Dion-Bouton combustion engineOutput: 2.5 hp (1.85 kW) per cylinder
Electric motor output: 2.7 hp (2 kW) per wheel
Top speed: 35 km/h (22 mph)
Range: 200 km (124 miles)
Overall width: 1,880 mm
Overall length: 3,390 mm
Overall height: 1,850 mm
Total weight:: 1.7 tons
Front wheel weight (single): 272 kg (with wheel hub motor)
Track width front: 1,350 mm
Track width rear: 1,540 mm
Wheelbase: 2,310 mm
Ground clearance: 250 mm
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