The European Commission identifies Hydrogen and fuel cells among the portfolio of technologies that could address the common energy problems. This technology is identified as having the potential to provide solutions for issues such as energy supply security, while reducing local air pollution and increasing employment. Hydrogen and fuel cells development and deployment requires large scale integrated actions with the necessary critical mass, as well as mobilising private business, Member States and the Commission in public private partnerships.
In 2000 the transit authorities of Amsterdam, Barcelona, Hamburg, London, Luxembourg, Madrid, Porto, Stockholm and Stuttgart decided to participate in a joint fuel cell bus and hydrogen fleet test to significantly enhance the development of Clean Urban Transport for Europe. They joined with leading infrastructure companies such as BP, Norsk Hydro, Shell and Vattenfall, and withDaimler Chrysler and its bus subsidiary Evobus. In order to strenghten the development of the new technology and to support the efforts of the transport companies, in 2001 the European Commission decided to support this project with one of the largest budgets ever for a single research and demonstration project.
The overall objective of the project was to develop and demonstrate an emission-free and low-noise transport system, including the accompanying hydrogen production and refuelling infrastructure.
This combination of these new technologies shows the greatest potential for the reduction of global greenhouse gas emissions and improving the quality of the atmosphere and life in densely populated areas, while conserving fossil resources. It also has the potential to strenghten the technological competitiveness of the European economy.
Specific objectives of the project were:
- Demonstration of 27 fuel cell powered Mercedes-Benz Citaro buses over a period of two years in European metropolitan areas in order to gain knowledge on the operational practicability of the fuel cell technology under real life conditions.
- Design, construction and operation of the necessary infrastructure for hydrogen production and refuelling stations. The hydrogen was produced partly on-site, partly off-site from different sources such as water (electrolysis), natural gas (steam reforming) and different processes in oil refineries.
- Development of the necessary knowledge to certify the fuel cell buses as well as the hydrogen infrastructure for safe operation in the participating European countries.
- To build-up a knoledge base on the environmental performance of the new transportation system through the lifecycle assessment approach and to compare the fuel cell technology with conventional technologies such as diesel/compressed natural gas powered buses.
- Increasing public knowledge and acceptance of fuel cell and hydrogen technology through the operation of the fuel cell buses in inner city areas.
The work programme was structured into the following different groups of activities addressing tasks and objectives of the project:
- Set-up and operation of the hydrogen production infrastructure. These actvities addressed issues relating to the supply of hydrogen. This was achieved either by on-site production or transportation (by truck) from distant sources). They also included the provision and use of the local infrastructure necessary for the operation of the buses consisting of a refuelling station and a bus depot.
- Operation of 27 fuel cell Citaro buses. This group of activities formed the heart of the project and concerned the demonstration ad evaluation of the behaviour and performance of the bus system in regular service in European inner city areas under different climatic, topographical and traffic-related conditions.
- Accompanying studies, which include the implementation of a Quality & Safety Monitoring system for the setting up and operation of a fuel cell hydrogen powered bus system, including the certification and homologation of the various system components. They also addressed issues concerning appropriate training and education of the personnel involved, as well as informing the public to give them a better understanding of this new propulsion system. Finally studies were carried out on the ecological and economic effects of introducing the new technology in Europe in order to better assess the medium and long-term effects of the new transport system.
- Exploitation and dissemination of the project’s findings.
1) Overview of the results
The fuel cell buses and some aspects of the hydrogen infrastructure gave surprisingly high levels of availability. The project also demonstrated that the vision of a future transport system based on fuel cells and hydrogen can become a reality when all the optimisation potentials identified in CUTE are realised and transferred into series production.
More than 4 Millions passengers were transported and directly experienced fuel cells. This extraordinary level of exposure is far greater than all other fuel cell projects currently running added together.
The distance driven and the number of operating hours of the bus fleet are perhaps the most impressive figures from this project. They document the huge step forward with regard to the lifetime and durability of the fuel cell system. Never before has a hydrogen technology project demonstrated such an outstanding operating success. Buses driven by regular bus drivers in regular traffic under normal operating conditions completed a distance of more than 20 times around the globe, producing a wealth of data and building a vast pool of experiences.
2) The fuel cell buses
- Over the 2 years of operation (the project finished in December 2005) the 27 CUTE buses travelled a distance of almost 865.000 km in the 9 partner cities and were operated for over 64.000 hours, demonstrating their reliability, collecting information and gathering experiences on fuel cell buses.
- The distance driven in each city ranged from some 40.000 km up to more than 140.000 km, depending on the conditions in the particular city, while the operating hours ranged from about 3300 hours up to close to 10.000 hours.
- The longest lifetime of a single fuel cell stack was more than 3200 operating hours, which greatly exceeded all expectations.
- The buses performed with a better than expected reliability and availability. The data obtained also showed the optimisation potential of this prototype bus with regard to fuel consumption. Simulations showed that the fuel consumption could be reduced by up to 50% using hybridisation and more elctric drive train related technology.
- The fuel cell technology itself and the hydrogen components did not show any significant weak-point, but other electrical components such as the inverter need to be improved.
3) The Hydrogen infrastructure
- All filling stations except one were operational (avai
- The overall cost structure must be improved for both the fuel cell buses and for the hydrogen refuelling technology including the production of hydrogen. The prices for fuel cell buses must be significantoly reduced in order to become competitive.
- The overall efficiency of the hydrogen production and distribution needs to be greatly improved.
- The durability and power density of the fuel cells has to be further enhanced, while the hydrogen storage systems need to be simplified and less expensive.
- The complete drive train of future fuel cell buses needs to be improved especially with regad to electrical components such as electric motors, high voltage battery systems and their associated control strategies.
- Community demand for the development of sustainable transport energies must become stronger in order to speed up the development and commercialisation of the technology.
- Increased community and political awareness must b translated into long term investment not only through the funding of projects such as CUTE, but also through the necessary legislative support. Currently the technology is still not mature enough to be rolled out in mass production within the next 5 years and this support is critical to reduce this time frame.