Environmentally-friendly and efficient citybuses from MAN at the UITP Congress

Environmentally-friendly and efficient citybuses from MAN at the UITP Congress

  • First presentation of the MAN hybrid bus series version
  • MAN Lion's City C with length of 13.7 m is new addition to range
  • New E28 natural-gas engine with greater performance

MAN Nutzfahrzeuge is presenting its current range of city buses and drive concepts at the 58th World Congress of the International Association of Public Transport (UITP) in Vienna (June 7 to 12, 2009), a range that consistently aims at the highest possible efficiency in transport. The technically sophisticated and attractively designed low-floor buses range from the 12-m solo bus to the new 13,7 m long Lion’s City C to large-capacity vehicles with a length of 18.75 m in city and intercity versions. Thanks to their MAN PURE DIESEL® technology, the MAN buses meet the voluntary EEV emission standard without the use of additives, which gives them a unique position in the market that cannot be matched by any other bus manufacturer today. The UITP will see the world premiere of the MAN Lion’s City Hybrid in the series version, the new low-floor MAN Lion’s City C city bus, and the new MAN E2876 LUH 03 natural-gas engine, with which MAN Nutzfahrzeuge once again demonstrates its outstanding competence in the area of environmentally-friendly drives.

MAN Lion's City Hybrid: the series version of the drive of the future

The series version of the new MAN Lion’s City Hybrid city bus, presented for the first time to interested trade visitors at the UITP, has a compellingly attractive EfficiencyDesign. Characteristic of this design are the Ultracap high-performance energy storage system, which is installed on the forebody due to favourable aerodynamics and weight distribution, the top-quality AeroLine in matt aluminium, which is drawn dynamically from the B-column to the roof surroundings, and the aerodynamically enclosed rear wheel housings. The hybrid logo located near the B-column points out unobtrusively that the vehicle on the go here represents the state of the art.

From a technical point of view, the hybrid bus is based on the current low-floor model of the MAN Lion’s City in tower design and the current D08 common-rail EEV 250-hp engine, equipped with a closed, electronically controlled CRTec® particulate filter. A small series of these solo vehicles will be taken into regular service in several European capitals during the course of 2010. The site of the exhibition, Vienna, as well as Munich are among the first cities in which hybrid buses from MAN will go into trial operation. Further cities will follow at the end of 2010. An individual solution tailored to the requirements of the articulated bus is being prepared for series introduction in 2012. This will also utilise the high-performance Ultracap technology.

Operation in city traffic provides ideal conditions for using braking energy. City buses accelerate an untold number of times to between forty and fifty kilometres an hour, only to decelerate to a standstill again shortly afterwards. Conventional buses transform the kinetic energy to wasted heat when they decelerate, while the Lion´s City Hybrid stores the braking energy to accelerate quietly away from the bus stop again, protecting the environment as it does so. Depending on the charge of the Ultracaps, the extent to which the vehicle is loaded and the topography, the hybrid bus can run up to several hundred metres purely on electricity. This means that passengers are largely spared noise and exhaust gas in the vicinity of bus stops. The integrated start/stop system doesn't just save valuable fuel near bus stops, though. Trials in real operation prove that, depending on the profile of the regular service, the diesel engine can be shut down for roughly 40% of the period of operation.

In the Lion's City Hybrid, MAN has created a whole package of measures to produce very respectable fuel savings. MAN's engineers reckon with fuel savings up to 30 percent plus substantially reduced emissions relative to conventional diesel engines. This is backed up by the results of around 35,000 kilometres of testing in regular service in Nuremberg and other European cities, absolved very successfully by several prototypes. The MAN Lion’s City Hybrid is also suitable for operation with second generation biofuels, which improves the already exemplary CO2 balance still further. With an average annual mileage of 60,000 kilometres the MAN hybrid bus saves the environment approximately ten tonnes of greenhouse gas.

Expansion of the modern range of city buses

MAN Nutzfahrzeuge offers an attractive range of highly efficient low-floor city buses, now fully concentrated under the MAN brand. The classic model in this range is the MAN Lion's City solo bus equipped with either the horizontal MAN D20 common-rail engine or the vertical MAN D08 CR engine in tower design. Major prizes for design, such as the iF Award, the reddot award and the title "Bus of the Year 2005" are clear evidence of the outstanding characteristics of this model range. The range's prize-winning design has been developed still further in 2009 with the new hybrid bus and its dynamic EfficiencyDesign.

Just as it did when the Euro 4 emissions standard was introduced in 2005, MAN is offering all its city bus engines equipped with additive-free MAN PURE DIESEL® technology, a technology which now meets the voluntary EEV standard for engines of all power classes. Since 2009, MAN has been offering engines that meet this most stringent of environmental standards for almost all city and intercity buses and coaches. Lion's City buses with 280, 320 and 360-hp horizontal D20 engines are equipped with CRTec® particulate filters as standard.

Due to requests from a large number of customers, the solo bus with tower design and D08 engine (optionally 250 and 290 hp) will be modified from super-wide tyring to conventional twin tyring in the model year 2009.

New in the range is the three-axle MAN Lion's City C solo bus in the comfortable length of 13.7 m. This model supplements the 14.7 m long Lion's City L which has been available up to now. With this new vehicle length, designed especially for the Swedish market, it stands out against buses of comparable passenger capacity (98 to 120 passengers with spaces for either one or two wheelchairs and 34 to 44 seats) thanks to its greater manoeuvrability and improved compactness. The turning circle has been reduced to 24.7 m by shortening the wheelbase by around a metre immediately in front of Door 2 (5.875 mm, the same as the two-axle version) in conjunction with the electro-hydraulically steered trailing axle. The noticeable swing-out at the back of these vehicles has similarly been reduced by 15 cm to a mere 1.16 m. The linear layout of this variant corresponds to that of the successful double-decker currently in regular service in Berlin and Dubai. In contrast to the 14.7-m version, this vehicle will be offered exclusively with three doors. Doors of all types will be available, including, for example, modern outward-swinging sliding doors. The range of engines available includes both modern common-rail 320 and 360-hp diesel engines in clean, EEV-compliant versions, equipped with MAN PURE DIESEL® technology. From 2010 on, the new MAN E2876 LUH03 natural-gas engine, which similarly delivers 320 hp, will also be available. From the outside, the new, beautifully-designed roof fairing will make this bus recognisable. With an unladen weight of between 13 and 14 tonnes and a registered gross vehicle weight of 24 tonnes, the vehicle has plenty of weight reserves, making it the ideal city bus for local transport authorities not wanting articulated buses. This vehicle is unique in its class and is available with immediate effect for all left-hand-drive markets.

Since 2006 the MAN Lion's City GL articulated bus has rounded off the range at the top length: the articulated bus with the maximum permissible length of 18.75 m provides space for up to 14 more people than the standard 18-m model. This model is powered by the MAN D20 common-rail engine.

New MAN E 2876 LUH 03 natural-gas engine

For several years already MAN's natural-gas engines have met the requirements of the voluntary EEV standard ("Enhanced Environmentally friendly Vehicle"). Because combustion produces very few emissions, complex filtering by means of closed particulate filters is unnecessary. With sales of more than 4,000 engines, buses and bus chassis, MAN is the market leader in the natural-gas powered bus segment. The new OBD2-capable MAN E2876 LUH 03 compressed natural-gas engine with a ten-hp higher output and greater torque will be presented at the UITP 2009 and available from 2010 in buses and chassis.

Just like the 245-hp MAN E2866 DUH04 natural-gas aspirated engine, which, from the introduction of OBD2 (the statutorily-required engine control system "On-board Diagnosis 2") will no longer be available for EU27 markets, the new 320-hp engine remains far below all the limits prescribed by the voluntary EEV standard . At the same time the maximum torque was increased by 150 Nm to 1,400 Nm, which puts it almost at the level of the comparable D20 diesel engine. Even though engine and exhaust-gas management can enable all MAN common-rail diesel engines to comply with the EEV standard today, the natural-gas engine still represents an environmentally-friendly, economical and future-oriented alternative. This applies in particular to local public transport authorities where the infrastructure and the corresponding natural gas are available at a reasonable cost. The new MAN compressed natural gas engine will be available from 2010 in low-floor city buses as well as bus chassis.

New gearbox versions for increased efficiency

From the second half of 2009 new gearbox versions and modern gear-change programs to increase efficiency will be available for the MAN city buses. In conjunction with the optimum drive train configuration, these will improve the already-good consumption values of the MAN common-rail engines equipped with MAN PURE DIESEL® technology.

From the time of their introduction onwards, the new ZF EcoLife gearboxes will be installed as standard in MAN buses, together with the topography-dependent TopoDyn gear-change software. This new generation of gearboxes excels with its higher input torque, its longer service life, the higher braking torques of its integrated primary retarder (increase of up to 650 Nm on the primary side) over longer periods as well as with its integrated electronic control. Thanks to the new converter with torsion damping, acceleration has been improved and gear changes made more comfortable, precisely in the lower gears. Fuel savings of up to five percent can be achieved with the topography-dependent TopoDyn gear-change software, which selects one of the five specific gear-change programs that are available in dependence on the topography and the load.

Moreover, the fifth generation of the Voith DIWA.5 gearbox will also be available in its tried and trusted versions. Outstanding features are as they have been up to now: electronic integration in the drive train, well-known and efficient mechanical-hydraulic power distribution and a powerful secondary retarder. Here too a new topography-dependent gear-change program, SensoTop, will be installed. This will result in the heavy-duty class also saving considerably on fuel, thanks to gear changes at optimum engine speeds. It distinguishes itself from other systems by utilising a separate, maintenance-free altimeter that detects inclines and declines, on the basis of which it makes a concrete calculation of the optimum points to change gear.