From 2030 no more diesel buses
Daimler e-Citaro – charging stops are no longer necessary
Next year, Mercedes wants to enter the e-Citaro with a significantly improved battery. The city bus should now have a range of 400 kilometers and thus manage its daily journeys without recharging. But the Stuttgart even revives an almost forgotten technology.
Citaro city buses with the Mercedes star circulate all over the world, so far almost all of them have a powerful diesel engine. Although the first electrically powered Daimler buses were added four years ago, with just 600 e-Citaros sold since then, Mercedes is number one in Europe but still plays a minor role. For comparison: in the Chinese city of Shenzen, which has a population of 12 million, there are nearly 18,000 electric buses.
In Mannheim, Till Oberwörder, head of Daimler Buses, announces that diesel will make its debut on city buses by 2030. The first new e-Citaro is expected to arrive in cities as early as next year. They can do everything better than before, they can travel up to 400 kilometers on a single battery charge, depending on the model, recharge faster than before and, above all, have a sort of “spare tank” on board. A 60 kWh hydrogen fuel cell produces electricity on board, which then supports batteries up to 686 kWh. This eliminates the need for “intermediate refills” in the depot, which previously slowed city buses on their daily runs.
Fuel cell as a range extender
The fuel cell comes from Toyota and acts as a so-called “range extender” capable of recharging the batteries while driving. A technique that is also known from automobiles. For example, the BMW i3, one of the first electric cars in Germany, had a 650cc two-cylinder petrol engine of a scooter, which integrated the battery, which from today’s perspective is modest, with just under 19 kW when it was threatened with collapse. As is well known, this idea of extending the range has not caught on in passenger cars.
Other dimensions apply to city buses. As before, the new generation of solid state batteries is composed of nickel, manganese and cobalt and is therefore referred to as NMC. The batteries of up to seven packs provide a good 70% more energy than the current e-Citaro model. In the articulated Citaro, they consist of up to 5,400 individual cells. The capacity of up to 686 kWh is huge compared to the 108 kWh of the Mercedes EQS luxury electric vehicle.
Charging also possible with pantograph
Depending on the size of the urban area, a customer can choose between different battery sizes and their possible ranges. A single bus, i.e. without the back of an articulated bus, can travel an impressive 300 kilometers. If the application area requires more kilometers, for example in cities with over a million inhabitants, the “Range Extender” comes into play, delivering another 100 kilometers. It is charged at the socket up to 150 kW. It is twice as fast with a so-called “pantograph”, as pantographs are called in technical jargon, for example on trains or trams. Such scissor-like structures can also be mounted on the e-Citaro.
Daimler is building an extensive service package related to the city bus business. Transport companies are advised so that their electric buses are tailored exactly to local needs. There is also support for expanding charging options at depots, including planning, construction work and electrical installation. Also included in Daimler’s carefree package are software programs for traffic control or remote monitoring.
The bus and truck departments work together on all innovations. Range extender technology could also end up in commercial vehicles. The next goal is the more climate-friendly operation of buses during long journeys. As a hybrid, the Mercedes Intouro with diesel engine is equipped with an additional electric motor that supports the combustion engine when starting or accelerating. The advantage is lower fuel consumption.