Mercedes-Benz OE 302

Mercedes Benz
An O 302 on which the OE 302 was based
OE 302
Manufacturer	Daimler Benz
design type	High-floor city bus
Production period	1969
axes	2
engine	Commutator machine + diesel motor OM 314
power	115 + 48 kW
length	11 m
Seats	65
Perm. total weight	16,000 kg
successor	OE 305

The Mercedes-Benz OE 302 was a hybrid bus from Daimler-Benz AG that was presented at the IAA in September 1969 . It was the very first hybrid bus and was based on the Mercedes-Benz O 302 . At least 25 copies were built. In December 1969, Daimler-Benz had not made any announcements that it would build the vehicle in series. The Society for Electric Road Traffic (GES) used the OE 302 in practical test operation. In the course of the test operation it became clear that the OE 302 had a higher primary energy requirement than a conventional diesel bus, and the operating costs were also higher.

Description and technology

The OE 302 was two-axle, eleven meters long and had a maximum permissible gross weight of 16 tons. It was painted a light color and had the inscription “Mercedes-Benz electric test bus”. It was designed as a high-floor city bus . The body was self-supporting. It was driven by an actively air-cooled commutator machine with a nominal output of 115 kilowatts and a peak output of 150 kilowatts. It was installed behind the rigid rear axle, interlocked with a reduction gear and connected to the rear differential with a short drive shaft . In the rear area behind the commutator machine, the diesel engine was installed transversely, a liquid-cooled inline four-cylinder four- stroke engine with direct injection of the type Mercedes-Benz OM 314 with a displacement of 3758 cubic centimeters and an output of 48 kilowatts. If the bus drove in the suburbs, the diesel engine was switched on to increase the range. It was operated at a constant speed in the optimal map area. Five battery blocks with a mass of 500 kilograms each, each with 189 cells and a total voltage of 380 volts, were installed in the underbody. They could store up to 91 kWh (327.6 MJ) of energy. Their lifespan should be 1500 cycles if they were discharged once a day. They enabled a top speed of 70 km / h and a range of around 55 kilometers if the bus was operated at a distance of 400 meters between stops. The accumulators were also actively air-cooled. In the front area of ​​the OE 302, an electrically driven air compressor with a pump for the power steering was installed. In addition, the bus had a recuperation brake . In 1974 a car was experimentally adapted for combined overhead line and battery operation and operated as such on the Esslingen am Neckar trolleybus until 1978 .

Web links

• Image of the vehicle in the Daimler-Benz archive
• Daimler AG: 40 years of Mercedes-Benz O 302: One for all

Individual evidence

1. ↑ Mercedes-Benz Austria: Mercedes-Benz buses with hybrid drive. Retrieved November 21, 2017
2. ↑ Mercedes-Benz Public Archive: Experimental vehicle C 111 presented at the IAA
3. ^ ^{A b} Association of the German Automobile Industry (ed.): Otto-Peter Bühler: Omnibus technology: historical vehicles and current technology , Vieweg, Braunschweig / Wiesbaden, 2000. ISBN 978-3-528-03928-8 . P. 235
4. ↑ Hearst Magazines (Ed.): Popular Mechanics , Volume 132, No. 6, December 1969. ISSN 0032-4558. P. 77
5. ^ German Transport Science Society (ed.): Internationales Verkehrwesen , Volumes 26-27. A. Tetzladd, 1974. p. 170
6. ↑ ^{a b c} Peter Hoffmann: Hybrid vehicles: an alternative drive system for the future , Springer, Vienna, 2014. ISBN 978-3-7091-1780-4 . P. 495 ff.
7. ^ Society of Automotive Engineers (ed.): Automotive Engineering , Volume 78, 1970. P. 42 ff.
8. ^ ^{A b} Rudolf Krebs: Five millennia of wheeled vehicles: 2 centuries of road traffic with thermal energy. Over 100 years of automobiles , Springer, Berlin / Heidelberg, 1994. ISBN 9783642935534 . P. 402 ff.
9. ↑ Description of the prototype MB OE 302 13 RStn DUO on obus-es.de, accessed on March 18, 2019