MAN Metropolis ultra-quiet and emission-free in the city – progressive heavy-duty hybrid truck concept
- At the IAA 2012, MAN is presenting a progressive concept: a heavy-duty hybrid truck.
- MAN Metropolis operates purely electrically in the inner city
- The world's first truck featuring a passenger-car diesel engine as range extender
- Modular energy storage located underneath the driver's cab
- Birdview system for enhanced safety
- Vehicle to be tested in the Brussels-Antwerp urban region by environmental provider SITA in a two-year field trial
In the Metropolis, MAN is showing an extraordinary truck at the IAA 2012. The Metropolis is capable of dealing with heavy-duty transport tasks in the city - without emissions and almost completely without noise. Using power from regenerative sources supplied by a normal socket, the MAN Metropolis drives and works without emitting any CO2. Its energy storage, a lithium-ion battery in modular construction, is located beneath the cab, guaranteeing maximum space for the body, optimal weight distribution and the highest safety levels. A quiet and efficient diesel engine from the Volkswagen Group generates on-board power as needed and functions as a range extender for the heavy-duty truck. The end of this year will see the MAN Metropolis starting a two-year field test as a refuse collection vehicle.
The logistical supply and disposal process in cities is facing new challenges. In future, increasing numbers of people will live and work in cities and meg-acities – metropolitan regions with several million inhabitants. The cities must overcome the challenges presented by a rapid rise in population numbers and simultaneous increases in air-purity and noise-reduction requirements. More and more conurbations are expected to introduce zero-emission zones in future, admitting only vehicles that can travel a defined route ultra-quietly and without generating emissions. Delivering supplies at night, for example, or waste disposal in the early hours of the morning could also help space out the volumes of municipal traffic.
With the Metropolis, MAN in cooperation with Benteler Engineering Services is researching the technical feasibility of a vehicle concept that will meet these future requirements for heavy trucks in an urban environment. To this end, MAN has gone beyond the hybrid approach dominating current thinking for heavy-duty trucks and has instead created a completely new type of drive architecture: The Metropolis is an electrically-powered truck based on an MAN TGS 6x2-4. Its electrical motor outputs 203 kW and drives the truck’s rear wheels via a two-speed automatic gearbox. The auxiliary units such as power steering, air compressor and hydraulic pump as well as the air-conditioning system are also operated electrically and are demand-controlled via the energy-management system, thus saving energy. A colour display in the cockpit informs the driver of the current energy parameters, such as energy recovery, battery status and charge mode. The MAN Metropolis thus offers extremely efficient, environmentally-friendly driving.
Energy is supplied by a modular lithium-ion battery with a maximum capacity of 105 kWh. Thanks to its plug-in function, the battery can be easily and conveniently recharged at the nearest mains socket. Energy storage is arranged beneath the cab, above the front axle, where the diesel engine of a conventional truck is located. The weight of the battery is thus on the front axle so that as before, the rear axles can bear the weight of the body and of the goods being transported. The weight saving achieved through dispensing with a conventional truck engine and gearbox offsets the extra weight of the hybrid system, so that the vehicle has exactly the same payload as the standard MAN TGS 6x2-4.
Thanks to new technologies, the energy density of vehicle batteries is being continually improved. However, batteries will continue to represent a significant weight factor for the foreseeable future. A battery that had to store the entire amount of energy required to operate a heavy-duty truck would take up a considerable part of that vehicle's payload. This is why the research vehicle has a so-called range extender on board. The range extender supplies the battery with electrical energy via a generator whenever it is needed.
The function of the range extender is filled by a modern, compact diesel engine designed for use in passenger cars. In the MAN Metropolis this is a V6 TDI engine from the Volkswagen Group: in conjunction with a generator, this engine ensures the efficient production of electricity. The three-litre TDI engine delivers 150 kW (204 hp). An engine management program is responsible for seeing that diesel engine always runs within its most efficient range in terms of consumption.
MAN Metropolis in hard practical test – as refuse collection vehicle
In order to test the practicality and the economic viability of the vehicle concept, MAN and SITA have chosen one of the toughest types of operation for a heavy truck in an urban environment: waste collection. The Metropolis will be operated, as a fully operational “front-line” vehicle, by SITA in Belgium from January 2013, with rigorous monitoring for a period up to two years.
SITA, a subsidiary of SUEZ ENVIRONNEMENT, is one of the leading pro-viders of waste management and recovery solutions and an expert in the waste cycle as a whole. The company aims to offer its clients solutions to collectively build green growth that is more respectful of people and consistent with the circular economy. SITA brings to the project its recent experience in design, development and the operation of low carbon emission vehicles such as the “Full electric collection truck” developed and used by SITA France since 2010. The primary difference between the two designs “Full electric” and Metropolis, is the introduction of a small diesel engine which is designed to act as a range extender by intermittently driving an electricity generator recharging the batteries and when needed, providing direct drive support.
SITA currently utilises several types of alternative fuel vehicles in Europe (Electricity, biodiesel, natural gas). The partnership between SITA and MAN, developed over several years, has allowed this exciting new solution to be brought from the drawing board to reality. Focusing on reducing greenhouse gas emissions generated by waste collection activities.
In low-noise mode, the MAN Metropolis drives using only electricity; the drive to lift the refuse containers and compress the waste is electro-hydraulic. To make this possible, the MAN Metropolis was fitted with a special hybrid body by Faun: the compression rear loader with lifter was specially designed for fully electrical operation and has a total capacity of 22 m³. Because driving and collecting operations are electrically powered, the noise of operation has been significantly reduced. The MAN Metropolis is way within the usual noise-restriction limits applying in inner cities. This means that operators will in future be able to provide supply and disposal services in the mornings/evenings when traffic volumes are reduced, without disturbing residents or impeding other municipal traffic. The refuse collection vehicles also offer better capacity utilisation.
Electric operation is designed for a full day shift, comprising two cycles each with four hours' collection work and a distance of 15 km in stop-and-go operation. The range extender is used only occasionally during the day shift. Viewing the balance as a whole, from the generation of electricity to the moving vehicle (well-to-wheel), the CO2 savings potential is a very big one: it will be the task of the field test from the end of 2012 on to verify and quantify this potential. The project aims to reduce CO2 emissions by 60 percent compared with a conventional diesel vehicle.
Vision for greater road safety in urban areas
In this project, SITA and MAN are particularly committed to enhance safety and risk prevention. The Metropolis concept vehicle will be equipped with a “Birdview" camera system, which visualises traffic in the vicinity of the vehicle for the driver, from a 360° bird's eye perspective. This system is in itself innovative technology aimed at further enhancing road safety in urban environments and simplifying safer manoeuvring for drivers.
The Birdview system consolidates the information from four individual camera pictures into visual information for the driver. The cameras are attached to the sides of the vehicle in the center. A graphic computer resolves the individual images to a three-dimensional overall image that is able to show various different angles.
The generated image is then displayed on a monitor for the driver. The information supplied by this image supplements the information the driver gets by looking out of the cab and using the mirror. The system automatically selects the viewing angle to suit the driving situation. For this purpose it evaluates vehicle information such as the direction in which it is travelling and its speed. For example, if the driver indicates a right turn, the perspective changes and visualises the area to the front right of the vehicle, where there may be pedestrians or cyclists. The all-round bird's eye perspective is also very useful for manoeuvring in areas where the driver has no clear view.