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| Fuel Cell Drive for
Municipal Commercial Vehicles mobile future - clean environment - hydrogen
Fuel cell drive project for municipal commercial vehicles The objective of this project is to develop a low-floor bus with fuel cell drive. The companies participating in the project are Siemens AG Energieerzeugung KWU (fuel-cell system), Siemens AG Verkehrstechnik (electric motors), Linde AG (hydrogen supply and periphery), MAN Nutzfahrzeuge AG (low-floor bus) and MAN Technologie AG (hydrogen storage system). The project is being coordinated by Ludwig-Bölkow-Systemtechnik GmbH and enjoys 50 % sponsorship from the Bavarian Ministry for Economics, Transport and Technology in the context of the Hydrogen Initiative Bavaria. By the year 2000 it is to be demonstrated that fuel cell drive systems can be used successfully for satisfying municipal transport requirements. Practical operation, e.g. with the City of Erlangen, will provide valuable information for the next stages in the development and market launch of hydrogen drive systems. The road to emission-free transport is mapped out Transport services by road vehicles are rendered predominantly using fossil fuel sources. The consequence of this is pollution, particularly in areas where there is a high traffic density. The growing world population with its increasing demand for mobility will further heighten the problems inherent in these conditions.
The prime objective of avoiding both local and global pollution for human beings and the environment is coupled with the necessary protection of resources. In view of the dimension of the problems a rethink is unavoidable. Only a responsible and sparing use of energy sources will lead to a compatible supply of energy worldwide that is orientated towards long-term objectives. Hydrogen - the fuel of the future Hydrogen is the earth's most common chemical element. Most of it, however, is bound in water and cannot therefore be used as a fuel directly. An input of energy, e.g. by electrolysis, allows hydrogen to be produced. The availability of hydrogen is thus almost unlimited. Used as a fuel for vehicles, hydrogen operating with a fuel cell produces no emissions. If hydrogen is generated with renewable energy in future, fuel cell vehicles will potentially be able to ensure completely emission-free transport of goods and persons. Fuel cell drive - clean and efficient The fuel cell reverses the electrolysis process. Here hydrogen and oxygen are transformed to water direct, whereby electrical energy is released. The special feature of the PEM fuel cell is a proton-conducting membrane which is coated on both sides with a catalyst and at which the chemical transformation of hydrogen and oxygen takes place. PEM fuel cells occupy an important position among the various fuel cell types. They are particularly suitable for use in mobile systems. PEM technology offers:
The fuel-cell bus To demonstrate the advanced drive concept to the public at large an MAN low-floor bus will be equipped with the components for a fuel-cell drive system. The hydrogen storage system consisting of lightweight composite cylinders will be mounted on the roof of the bus. In these cylinders sufficient hydrogen for a range of about 200 to 300 km will be stored in compressed form. Fuel-cell modules with a total output of 120 kW will generate electrical energy for operation of the bus with two asynchronous motors. These two motors will be linked by a summation gearbox. Other components of the fuel cell system and the electric drive system will be housed at the rear of the vehicle. If fuel cell drive is used there will be no local emissions. In addition the electric drive system makes the bus extremely quiet and gives it a very high level of ride comfort.
Composite materials compressed hydrogen storage Prospects Hydrogen as fuel can considerably improve the environmental balance in the transport sector. Its use in vehicles is characterised by an excellent emission balance. If renewable energy sources are used the process of preparing hydrogen too can be designed on environmentally friendly lines. Fuel-cell drive has a number of features which make it a promising alternative to conventional vehicle propulsion systems. At present, however, fuel cells are very expensive and their use is limited because of the space they require in the vehicle and because of their weight. Intensive further development of fuel cell technology, the vehicle drive systems, the storage technology and the entire infrastructure will be necessary as preparation for switching to non-fossil energy sources if this switch is to be made in good time. As an almost inexhaustible source of energy hydrogen offers the best basis for this.
Table: Technical data on MAN low-floor bus with fuel-cell drive Contacts: MAN Nutzfahrzeuge AG · Postfach 50 06 20 Siemens AG·
Energieerzeugung (KWU) · FRN 4 Siemens AG ·
Verkehrstechnik · VT 51 MAN Technologie AG ·
Postfach 13 47 Linde AG· Werksgruppe
Technische Gase · Seitnerstraße 70 Ludwig-Bölkow-Systemtechnik GmbH · Reinhold Wurster |
