FIRST DRIVE | 17
eCitaro
from Mercedes-Benz
O
f t he com mercia l vehicle manufacturers, Mercedes-Benz was later than most to bring a fully electric bus to the market. One of the statements from the German brand when asked about progress in having an electric bus was that “we do not want to be the fi rst, rather the best.” Well, at last it has arrived, as the MercedesBenz eCitaro is now available for delivery (with right-hand drive versions available mid-2019). At the end of last year, the City of Hamburg took delivery of two electric Citaros, the fi rst of an order of twenty. The operator, Hamburger Hochbahn, runs 1,000 buses with a commitment that by 2020 it will only purchase emission free buses. Furthermore, it plans to have no diesel engine buses in its fleet by 2027. From an Irish perspective, some commitments have been made by the Irish Government on behalf of Transport Infrastructure Ireland (TII) in terms of more environmentally friendly buses, so let us hope sensible and cost effective decisions are made here. Going to alternative power is not as simple as buying vehicles. Daimler Bus CEO Gustav Tuschen stated recently that system design and consultancy are just some of the services the company provides to cities and companies considering introducing improvements for their public transport system. Irish cities need to make decisions around sustainable transport and should take all advice that
Text: Sean Murtagh - sean@fleet.ie
is available. In putt ing plans together the decision makers should be mindful of Mr. Tuschen’s statement:“electric power does not mean the end of the internal combustion engine, bio-gas engines are almost at zero emission, the goal is to reduce CO2 emissions overall.” eCitaro from a driver’s point of view Up to the end of last year, over 55,000 Citaros have been delivered to customers all-over the world. It is a bus that has seen many improvements in design and quality since its debut. The driver’s area is similar to previous models, while storage areas are generous and handy, and all of the regular controls within easy reach. Noise levels in the Citaro have always been at a low level and therefore any reductions in the new bus are not as immediately noticeable. Some developments in the steering are positive and an improved curvature on the windscreen improves visibility. One noticeable feature is how the bus can “coast”. When one takes the foot off the accelerator, it freewheels rather than going into retard mode. Of course, one can set it to retard, allowing the unit to regenerate energy from the braking action. As a driver, some experience is required to decide which is the more economical method. Some training will help here. Something else that adds to the simplicity of driving is the instrument display cluster. Over the years, I have driven electric buses where the functions of various gauges for battery consumption and regeneration were difficult to make sense of, even when explained. eCitaro has replaced the revcounter from the diesel bus with a power
meter. Remaining battery life is displayed in a similar fashion to a fuel gauge. Safety Mercedes-Benz is offering “Side Assist” on the new eCitaro, offering a new level of protection to pedestrians and cyclists. Th is radar type function picks up a cyclist or pedestrian on the driver's offside. It will also detect a traffic bollard. A warning indication will appear on the dash while a small icon on the exterior mirror illuminates. If the driver does something that causes the system to think a collision is imminent - such as making a steering movement to the left, it will intervene. Battery Management Successful operation of electric buses requires careful management in advance of use. The trade-off is between range distance and weight. Charging is also a consideration, most will rely on plug-in charging in the depot at night time but for some it may be necessary to have “opportunity charging” during the day at the depot or at locations along the services route. Standard equipment on the Citaro is two battery packs containing 8 cells in all, two at the front and six at the rear. The number can increase to ten, but the extra weight will reduce the number of passengers carried. In normal, circumstances, the range distance is estimated at 250km. However, in extreme weather this can be reduced to 150km. One thing that all manufacturers are saying is that with the improvements taking place in battery development, more efficiency is to come in the near future. Something cities and operators should keep in mind when making decisions. www.fleet.ie