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E-mobility: european visions and experiences

Development prospects of the E-bus technology


A conversation between Catia Chiusaroli, Co-ordinator of the Urban Plan for Mobility of the Metropolitan City of Bologna, and Anja Georgi, CEO of Mobilität Stadtwerke Offenbach, the public transport company in Offenbach (Germany). A collection of real experiences and reflections that give a glimpse into what the developments of e-mobility in public transport are and could be in Europe in the next 10 years

E-bus technology is rapidly growing in the field of public transport services. What is the main E-bus public transport services project you are working on, or have already implemented? What are the main innovative features? What are the expected benefits or those being generated in terms of social and environmental impacts?


Anja Georgi – In the last two years we have “redesigned” our bus depot to make the use of e-buses for public transport in the city of Offenbach possible. The first seven e-buses have been running in public service since December 2020 and 17 more are on their way by June (at the latest). In Autumn 2021, 12 more e-buses will be integrated into our fleet so that nearly 50% of the whole fleet will be e-buses by the end of the year.

Previously, a bus was replaced by another bus with higher emission standards. Now the main innovative feature is the We expect a huge impact on the environmental side concerning emissions (CO2, NOx and noise),

complete change of the drive type which goes along with the change in infrastructure, driving and repairing skills and also a totally different planning of routes and services. So nearly everybody in the company has to update their knowledge to make this change work.

a smoother drive experience for the drivers and users of public transport and, in the long term, we want to generate financial benefits concerning energy, repair and maintenance costs.

Catia Chiusaroli – The first project we are working on is the Metrobus lines, road corridors that have been designed to provide a fast, frequent, efficient, convenient, effective, sustainable and recognisable metropolitan public transport service. The Metrobus lines are part of the Metropolitan Public Transport (TPM) network envisaged by the Urban Plan for Mobility (PUMS), and are closely connected to the Metropolitan Railway Service (SFM), which has more than 83 stations within the metropolitan area, and the tram network of Bologna, consisting of 4 lines.

The Metrobus lines are the first fully electric solution to serve the metropolitan area, responding to the need to connect the metropolitan municipalities with Bologna through fast and frequent services, especially in areas not served by the SFM.


The vehicles are fully electric, calibrated for lines about 30 km long, and with a vehicle rotation system designed to limit the number of recharging points at the terminals while maintaining the efficiency of the batteries.

The project allows a reduction of 20% in LPT emissions in terms of COequivalent compared to an increase of more than 50% in the offer on the two routes concerned, net of the reorganisation of the adduction networks. If only renewable sources are used for recharging electric vehicles used for the Metrobus service, the cut in emissions would be more than 4,000 t of CO2equivalent a year. Then there is the addition of benefits arising from the diversion to LPT of more than the 900,000 movements a year currently made with more polluting types of transport.

Another innovative aspect is the type of infrastructural solutions and interventions that enable land consumption to be limited, if not eliminated, in compliance with regional laws in force, and therefore with further attention to the environmental sustainability of the project.

Lastly, the service envisages the use of ITS and MaaS systems to improve its performance, info-mobility, ticketing systems, safety, recharging systems, and management of traffic lights, etc., all in an integrated manner, at both metropolitan and municipal levels.

Socially, we expect to be able to provide all metropolitan citizens with a high-level, zero-emission public transport service that is a valid alternative to use of the car, thus increasing the modal split in favour of sustainable modes, reducing atmospheric emissions, and also reducing congestion in the central area.

The Metrobus network coherently integrates and interchanges with all the other transport modes and road public transport services, which are the adduction services to the Metrobus, so that the catchment area can be widened as much as possible, increasing the equity of transport services in the metropolitan area and reducing inequalities in the economic and social opportunities of the metropolitan citizens. This element is very important because it allows for better liveability of the entire metropolitan area and therefore more widespread competitiveness.

The project also envisages the redevelopment of all the platforms and shelters, and also the cycle and pedestrian access routes, so that architectural barriers can be taken down, universal accessibility guaranteed and user safety improved, not only through the reorganisation of shared spaces but also through the use of ITS systems. The improved performance of the service will also allow for a significant reduction in travel time, enabling the so-called “catch-up” and bringing services closer to all metropolitan citizens.

The energy supply of public transport fleets is a relevant issue today. Electricity and hydrogen are the main alternative technologies to the traditional power supply, posing new challenges, both in terms of infrastructures and processes. In the next 10 years, what evolution do you think the E-bus will have in this new context nationally (respectively in Italy and Germany) in terms of diffusion, development and use?
What infrastructural constraints and what opportunities do you see for the E-bus?

Catia Chiusaroli – National policies are moving cohesively towards fleet reconversion on several fronts. On one hand, the Ministry of Infrastructure and Sustainable Mobility has set up a fund for financing rapid mass transport systems, also including the so-called “electric busways”, powered by continuous or discrete systems; on the other, the National Strategic Plan for Sustainable Mobility has provided for multi-year funding (2019 – 2033) of over 3.7 billion euros aimed at regions, metropolitan cities and municipalities with more than 100,000 inhabitants. The aim is therefore to support public administrations in faster renewal of their LPT fleets, speeding up the implementation of the European DAFI directive and supporting the production chain of alternative fuel fleets. In addition, all the PUMS approved in recent years by the municipalities and metropolitan cities required to draw one up, provide for a progressive modernisation of fleets towards more environmentally friendly, mainly electrically powered, vehicles.

This context also favours research by manufacturers and progress in the technology of charging systems and battery performance. I therefore believe that the evolution towards e-buses is a very valid option that will see rapid development in the coming years.

However, the various players in this process need to pay particular attention to the overall sustainability of the policy with specific focus on the issue of energy production from renewable sources and the management of the entire life cycle of batteries.

Infrastructural constraints can be many, as happens during the development of new technologies that have to face a number of different challenges. As far as infrastructural constraints are concerned, we can already see issues related to the location of electricity substations capable of powering increasingly large fleets, and also the risks of electromagnetic pollution.

The opportunities are obviously linked to the benefits discussed above but also to the development of new technologies necessarily linked to the development of this type of material and the related ITS and MaaS technologies.

Anja Georgi – Nobody will deny that there is a general need to reduce air pollution while offering the needed mobility. To prevent driving bans for combustion vehicles in city centres, we have to think about new technologies for transport and especially public transport as these vehicles run millions of kilometres per year in cities. Regardless of whether we choose BEV or HEV buses, we are able to support the European, national and local goals to reduce all emissions set by the Clean Vehicle Directive by using the great potential of electric buses. Many practical examples worldwide already show that the future is buses with alternative drive technology.

As Ms Chiusaroli mentioned, battery performance is a key for more use in different transport situations. There is a need to build new value chains concerning the development of batteries and drive technology (e.g. range and resource optimisation) to make sure that batteries can be re-used as energy storage or dismantled for re-use of the rare raw materials.

In this way, as my colleague said, we’ll be able to “spoon out” the whole life cycle of batteries without wasting any materials – another precondition to protecting our environment.

This transformation of driving technology goes along with the megatrend of digitalisation which will become more and more important for public transport in the next 10 years. Topics like depot management, avoidance of load peaks to protect the energy network and also customer requirements in modern mobility “mobility as a Service” modes will require a totally different strategy of the bus companies compared to the last few decades. I am totally convinced that the concerns about how far e-buses can go, at the moment, a really important point, will no longer be a problem in 10 years’ time.

Italian Ministry of Transport guidelines regarding low-emission public transport funding have led to investments in this area. Is the German regulatory framework going in the same direction? Do you believe that further specific local factors will influence investment decisions on the E-bus – flexibility of the network, orography of the area and level of mobility demand? Did some of these factors enter your choice process? Did you consider any others? If so, which ones?

Anja Georgi – Yes, there are some programmes in Germany which are run by different Ministries (mainly Transport and Environment) on different levels – i.e. the federal state and small towns – to support the change in public transport by co-funding. Public transport operators are able to invest in this new technology just based on this. Everyone has certainly got to consider local circumstances for the implementation of low emission public transport. Our main point was to make sure that the services can be run by the same number of drivers and the same number of buses as before because, otherwise, the extra costs for this technical change would have been too high. Therefore, we started with a pre-study to show what was needed to reach this goal and what technical and financial resources would have to be available to implement the project.

We also considered other fuels like gas or hydrogen. But the circumstances, like the (local) zero emission goal and the impossibility of moving to a newly-built depot, so we had to work round a depot more than 130 years old surrounded by railway tracks, housing and a historic graveyard, made this step even more challenging while running normal services. So there is no “one project plan suits all”. You can learn about the kind of challenges awaiting you and how to deal with those points by talking to colleagues from other cities and companies but, in the end, you have to develop your own project plan tailored for your specific local factors.

Catia Chiusaroli – I agree with my German colleague that local factors and the relative costs of an electric public transport system must be considered in the definition of the service. It’s not just a question of the features of the technology and area but also being able to seize the investment opportunities and create synergic projects so that investments can be optimised, infrastructure shared between different LPT services created, accessibility improved overall with sustainable vehicles and the existing elements (infrastructure, recharging systems, depots, etc.) valorised.

Differently from Germany, the Metrobus service designed by the metropolitan city has also been strengthened in terms of an increase in frequency and numbers in the fleet to meet the aim of the PUMS of increasing the current modal share of LPT use by more than 6 percentage points by 2030, taking it to 20% in the metropolitan area. This is an ambitious objective but it is imposed by the air quality in the Po valley.

Despite the recent development in the use of methane fuels (CNG and LNG), the choice has been oriented to electric power, given the close interconnection between metrobus lines and the Bolognese tram network, the planned development of the trolley-bus networks in the Bolognese region and also to achieve the clean air objectives in the most effective way.

Some alternatives were assessed:

  • the traditional trolley-bus;
  • the In Motion Charge trolley-bus;
  • e-buses with maximum battery capacity and recharging stations at the terminuses;
  • e- bus with minimum battery capacity and flash recharging stations along the route.

After analysing the capacity of the vehicles, the features of the route and the compatibility of the system with the regional and technological contexts, the operational model, the overall costs of the system, the flexibility, autonomy of the batteries, recharging, positioning and type of recharging systems, etc. the best choice in terms of costs/benefits (social, environmental and economic) was the e-bus with maximum battery capacity and recharging stations at the terminuses.

Given the number of variables at play, each project must be adapted to the specific context. I agree with my German colleague on the fact that a comparison with the experiences of other cities is useful in enlarging the technical horizons, understanding their limits and potential and the implications but, in the end, they are made-to-measure projects.

After graduating in Regional, Urban and Environmental Planning, Catia Chiusaroli worked in the consultancy, research, design and co-ordination of mobility and town planning for several years. She has been Head of Mobility Planning for the Metropolitan City of Bologna for more than 15 years and, since 2017, she has also been Head of the Urban Sustainable Mobility Plan.

Anja Georgi is a member of the Hessian Public Transport Systems consortium and the Financing and Customer-Services Committee of the German governmental Public Transport consortium. Since 2001, she has written several articles for DER NAHVERKEHR, the leading monthly magazine for public passenger transport in the German-speaking world. She is a speaker at events on Public Transport worldwide. She has been CEO of the Mobilität Stadtwerke Offenbach (Germany) since 2013.

Suburban Infrastructure for E-Buses