The internal combustion engine seems the perfect drive system for passenger cars and commercial vehicles. Since the invention of the gasoline-powered automobile in 1886 by Karl Benz and Gottlieb Daimler, each working independently of the other, and the subsequent introduction of the diesel engine, it has become the global standard. This has been helped by the many advantages it offers: today’s engines are powerful and refined, relatively compact, durable, and require little maintenance. Energy supplies in the form of fuel can easily be transported and replenished as and when required. The range of distances that can be traveled is large, and there is a dense network of gas stations. The vehicles are easy to operate and offer great flexibility of use. Additionally, over the years, the drive systems have managed to keep pace with ever more stringent environmental regulations. Daimler AG and its predecessor companies have played major roles in this development.
Yet, despite the enormous technological advancements over more than 120 years of automotive history, vehicles with internal combustion engines are still merely an approximation of the ideal automobile. The growing awareness of environmental issues and one’s own health risks gives rise to ever greater demands for propulsion concepts other than the conventional ones.
Technology categorizes solutions of this kind under the heading “Alternative Drive Systems.” This encompasses all types of technical propulsion using any other means than an internal combustion engine, and the definition also extends to vehicles other than road vehicles: Solutions are being sought for automobiles, and equally for ships and airplanes. Which, in the best tradition of things, brings us back to Gottlieb Daimler, who always spoke of motorization “on land, on water and in the air” when describing the areas of application for the internal combustion engine.
From a present-day perspective, for example, alternative drive systems include fuel cells using hydrogen as an energy carrier, and also all-electric drive systems.
Researchers are also focusing on new fuels for use in conventional engines as possible replacements for gasoline or diesel, such as alcohols or gases. A special role is played by internal combustion engines other than the widely used reciprocating piston engine, for example the Wankel, Stirling, or turbine engines. And hybrid concepts are constantly considered to be the bridging technology to achieving a zero-emission drive system. In today’s automobiles, these generally consist of a combination of combustion engine and electric motor.
So there are many different variants for alternative drive systems, illustrating just how much scientists and engineers enjoy experimenting. And there are good reasons for this: they want to provide the automobile of the future with a better drive system, one that is cleaner or more economical, for example, than existing systems. This search will not end at a particular point, but will be constantly repeated after each new and successful innovation.
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Group photo: In the 1970s and 1980s, Mercedes-Benz tested different propulsion concepts – with a correspondingly large fleet of test vehicles. The photo was taken on the test track in Stuttgart-Untertürkheim in 1981. |
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Group photo: In the 1970s and 1980s, Mercedes-Benz tested different propulsion concepts – with a correspondingly large fleet of test vehicles. The photo was taken on the test track in Stuttgart-Untertürkheim in 1981. |
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Mercedes Electrique: “The most reliable, quietest and most modern electric city car.” Advertisement of 1907. |
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Rapid start: In 1908, the Berlin fire brigade opted for the Mercedes Electrique with electric drive and purchased a fleet consisting of four vehicles. The wheel hub motors in the front wheels are clearly visible. |
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Mercedes Mixte on the front cover of the magazine “La France Automobile”, edition of November 9, 1901. |
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Environment-friendly electric drive: The Mercedes-Benz LE 306 of 1972 featured a battery exchange system which accelerated the “refueling”. The vehicle was extensively tested. |
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Environment-friendly electric drive: The Mercedes-Benz LE 306 of 1972 featured a battery exchange system which accelerated the “refueling”. The vehicle was extensively tested. |
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Environment-friendly electric drive: The Mercedes-Benz LE 306 of 1972 featured a battery exchange system which accelerated the “refueling”. The vehicle was extensively tested. |
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Environment-friendly electric drive: The Mercedes-Benz LE 306 of 1972 featured a battery exchange system which accelerated the “refueling”. The vehicle was extensively tested. |
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Ready for boarding: Mercedes-Benz city bus with hybrid electric drive of 1979. The internal combustion engine powered a generator which produced electricity for the traction motor. |
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Ready for boarding: Mercedes-Benz city bus with hybrid electric drive of 1979. The internal combustion engine powered a generator which produced electricity for the traction motor. |
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Ready for boarding: Mercedes-Benz city bus with hybrid electric drive of 1979. The internal combustion engine powered a generator which produced electricity for the traction motor. |
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Diesel-electric operation in cities: In the Mercedes-Benz Cito (1998), a four-cylinder engine powered a generator which produced electricity for the traction motor. Purely electric operation was possible over short distances. |
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Diesel-electric operation in cities: In the Mercedes-Benz Cito (1998), a four-cylinder engine powered a generator which produced electricity for the traction motor. Purely electric operation was possible over short distances. |
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Energy providers: The Mercedes-Benz OE 302 electric test bus (1969) needed five battery modules which were installed underneath the floor. |
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Diesel-electric: The Mercedes-Benz OE 302 test city bus was powered by electricity, its batteries being charged by a diesel engine. This vehicle marked a new start in hybrid drive development in 1969. |
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No clutch pedal: The driver of the Mercedes-Benz OE 302 electric test bus (1969) only had to actuate the accelerator and brake with his feet. |
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Diesel-electric: The Mercedes-Benz OE 302 test city bus was powered by electricity, its batteries being charged by a diesel engine. This vehicle marked a new start in hybrid drive development in 1969. |
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Early example of an electric car: The chassis of the 30/35-hp Mercedes with wheel hub motors (built from 1905 until 1909). |
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Refueling at the mains: Two Mercedes-Benz test vehicles with electric drive, photographed in 1995. |
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Testing in the early 1990s: Mercedes-Benz MB 100 D van with electric drive; a city bus version of this model was also set up. |
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Large-scale electric-drive test on the island of Rügen in 1992: Mercedes-Benz contributed ten 190 cars and ten MB 100 D vans. |
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Large-scale electric-drive test on the island of Rügen in 1992: Mercedes-Benz contributed ten 190 cars and ten MB 100 D vans. |
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Emissionsfrei unterwegs: Der in Serie gefertigte Duo-Bus, hier ein Exemplar aus dem Jahr 1993, hat einen reinen Elektroantrieb mit doppelter Energiezufuhr. Die Antriebsenergie kommt entweder aus einer Unterflur-Batterie oder gelangt per Oberleitung ins Fahrzeug („O-Bus“). Das bringt Flexibilität abseits des Leitungsnetzes. |
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Transparency: The X-ray picture of a Mercedes-Benz C-Class with electric drive of 1993 shows the layout of components. |
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Large-scale electric-drive test on the island of Rügen in 1992: Mercedes-Benz contributed ten 190 cars and ten MB 100 D vans. |
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Test car with ZEBRA battery: Mercedes-Benz 190 with electric drive, 1993. |
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Large-scale electric-drive test on the island of Rügen in 1992: Mercedes-Benz contributed ten 190 cars and ten MB 100 D vans. |
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Novel electric drive: The Mercedes-Benz 190 used as a test car in 1991. |
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Novel electric drive: The Mercedes-Benz 190 used as a test car in 1991. |
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Large-scale electric-drive test on the island of Rügen in 1992: Mercedes-Benz contributed ten 190 cars and ten MB 100 D vans. |
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Zero-emission motoring in the city: In July 2006, the smart brand launched a pilot project in London. The fortwo ed (electric drive) generates an output of 30 kW (41 hp) for adequate performance and has a range of some 100 kilometers (62 miles). |
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Zero-emission motoring in the city: In July 2006, the smart brand launched a pilot project in London. The fortwo ed (electric drive) generates an output of 30 kW (41 hp) for adequate performance and has a range of some 100 kilometers (62 miles). |
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High level of ride comfort: In early 1982, Mercedes-Benz began testing electric drive systems in passenger cars. The station wagon from the 123 series largely corresponded to the production version but its load compartment was reduced in size by the fact that it accommodated the battery. |
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High level of ride comfort: In early 1982, Mercedes-Benz began testing electric drive systems in passenger cars. The station wagon from the 123 series largely corresponded to the production version but its load compartment was reduced in size by the fact that it accommodated the battery. |
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High level of ride comfort: In early 1982, Mercedes-Benz began testing electric drive systems in passenger cars. The station wagon from the 123 series largely corresponded to the production version but its load compartment was reduced in size by the fact that it accommodated the battery. |
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Testing in city traffic: Mercedes-Benz 307 E van with electric drive (1980). |
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On the test track in Stuttgart-Untertürkheim: Mercedes-Benz 307 E van with electric drive (1980). |
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Propulsion energy at times of hardship, available ex factory: Mercedes-Benz 170 VG (1935) with wood gas burner. |
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Mercedes-Benz L 307 van of 1975: Test vehicle with hydrogen propulsion and hydride storage unit. |
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Test bus of 1971: The six-cylinder spark-ignition engine of the Mercedes-Benz OG 305 operated on natural gas – with very low pollutant emissions. |
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Prototype with electric drive: The Mercedes-Benz A-Class (W 168 series) of 1998 derived its energy from a ZEBRA high-performance battery on a sodium/nickel chloride basis. |
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In 1992, Mercedes-Benz presented a “Flexible Fuel” test car based on the 300 SE S-Class model (140 series). It engine management was designed for variable mixed methanol/ gasoline operation with a methanol proportion of up to 85 percent. |
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Adjustable engine management: In 1990, Mercedes-Benz presented the 300 E-24 for variable mixed methanol/gasoline operation. |
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Special setup: The Mercedes-Benz 450 SL test car (R 107 series) of 1974 had a spark-ignition engine optimized for operation on methanol. The engineers used the console and additional switches for controlling and monitoring the fuel system. |
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Three test vehicles from Mercedes-Benz (from left to right): LE 306 electric van (1972), OE 302 electric test bus (1969), OG 305 natural-gas test bus (1971). |
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Energy carrier for the future: In 1988, hydrogen was tested as a fuel in Mercedes-Benz vans and passenger cars. |
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Mercedes-Benz 200, 1981: Test car for the combined supply of the internal combustion engine with gasoline and liquefied gas. |
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Methanol operation and energy recuperation: The Mercedes-Benz O 305 test city bus on the test track in Stuttgart-Untertürkheim (1981). The vehicle was also tested in regular service. |
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Environment-friendly vehicles: Mercedes-Benz city bus with electric drive, van with electric drive and passenger car (123 series) for mixed methanol/gasoline operation. The photo was taken around 1980. |
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Methanol as a fuel: In 1979, the Federal German Ministry of Transport launched a research project named “Alternative Energies for Road Traffic”. Mercedes-Benz participated in a field test in Berlin with different vehicles, among them the 230 model (123 series). |
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Methanol as a fuel: In 1979, the Federal German Ministry of Transport launched a research project named “Alternative Energies for Road Traffic”. Mercedes-Benz participated in a field test in Berlin with different vehicles, among them the 230 model (123 series). |
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Gratifyingly low emissions, more efficient power output: The Mercedes-Benz 450 SL test car (R 107 series) with a spark-ignition engine optimized for operation on methanol was presented to the public in 1974. |
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B-Class F-Cell |
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NECAR 1, 2 and 3: From van to A-Class. |
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Mercedes-Benz Concept Vehicles, NECAR 1: An MB 100 van served as basis. |
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Mercedes-Benz Concept Vehicles, NECAR 1: The cargo space is packed with equipment. The stacks are arranged beneath the yellow hydrogen flask. |
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The Technology of the Fuel Cell and its Operating Systems, The operating principle of the fuel cell. |
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Matured: After the completion of the test stage, several units of the NGT Sprinter (Natural Gas Technology) were put into service, for instance by RHENAG in April 1996. |
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Matured: After the completion of the test stage, several units of the NGT Sprinter (Natural Gas Technology) were put into service, for instance by RHENAG in April 1996. |
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In 1992, Mercedes-Benz presented a “Flexible Fuel” test car based on the 300 SE S-Class model (140 series). It engine management was designed for variable mixed methanol/ gasoline operation with a methanol proportion of up to 85 percent. |
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Hydrogen testing: Mercedes-Benz also investigated the suitability of hydrogen as an energy supplier for internal combustion engines in vans. |
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On the way into the future: Different vehicles – the photo shows a Mercedes-Benz 230 E – were used in 1993 for testing hydrogen as a fuel for the internal combustion engine. |
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On the way into the future: Different vehicles – the photo shows a Mercedes-Benz 230 E – were used in 1993 for testing hydrogen as a fuel for the internal combustion engine. |
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Production car: In March 2006, smart presented the forfour lpg (liquefied petroleum gas) with a liquefied-gas tank in addition to the gasoline tank. In combined operation, the car has a range of 1,300 kilometers (over 800 miles). |
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Production car: In March 2006, smart presented the forfour lpg (liquefied petroleum gas) with a liquefied-gas tank in addition to the gasoline tank. In combined operation, the car has a range of 1,300 kilometers (over 800 miles). |
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Production car: In March 2006, smart presented the forfour lpg (liquefied petroleum gas) with a liquefied-gas tank in addition to the gasoline tank. In combined operation, the car has a range of 1,300 kilometers (over 800 miles). |
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Spectacular test car: The Wankel or rotary-piston engine was tested in the Mercedes-Benz C 111-I (1969, shown in the photo) and C 111-II (1970). |
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Spectacular test car: The Wankel or rotary-piston engine was tested in the Mercedes-Benz C 111-I (1969, shown in the photo) and C 111-II (1970). |
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On the way into the future: Different vehicles – the photo shows a Mercedes-Benz 230 E – were used in 1993 for testing hydrogen as a fuel for the internal combustion engine. |
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V8 gasoline engine with cylinder shutoff, six-cylinder diesel engine with turbocharger, gas turbine: The Mercedes-Benz Auto 2000 research car (1981) was used for testing these three propulsion systems. |
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V8 gasoline engine with cylinder shutoff, six-cylinder diesel engine with turbocharger, gas turbine: The Mercedes-Benz Auto 2000 research car (1981) was used for testing these three propulsion systems. |
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V8 gasoline engine with cylinder shutoff, six-cylinder diesel engine with turbocharger, gas turbine: The Mercedes-Benz Auto 2000 research car (1981) was used for testing these three propulsion systems. |
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V8 gasoline engine with cylinder shutoff, six-cylinder diesel engine with turbocharger, gas turbine: The Mercedes-Benz Auto 2000 research car (1981) was used for testing these three propulsion systems. |
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V8 gasoline engine with cylinder shutoff, six-cylinder diesel engine with turbocharger, gas turbine: The Mercedes-Benz Auto 2000 research car (1981) was used for testing these three propulsion systems. |
