Dresdner Verkehrsbetriebe uses the OMNIplus Driver Training course to familiarise its drivers with the fully electric eCitaro. Mercedes-Benz Omnibus Magazine was there to observe.
Omnibus Magazine
“Learning to sail with the eCitaro”
The OMNIplus Driver Training course fully explores the all-new possibilities of the eCitaro.
“Learning to sail with the eCitaro”
Today, in central Dresden, a very special bus trip is taking place. On board the Mercedes-Benz eCitaro are nine drivers from Dresdner Verkehrsbetriebe (DVB) and Jörg Spieß from Bus & Coach Training OMNIplus. The experienced driving trainer is on an exciting mission. His task is to acquaint the drivers with the fully electric city bus. The goals of the session: to drive with the greatest level of safety and control, while saving energy.
20 eCitaro buses for Dresdner Verkehrsbetriebe.
The ride is just one part of the professional OMNIplus Driver Training course, during which, on this sunny day in April, the DVB drivers will be familiarised with the fully electric city bus. The public transport company in the Saxon state capital is to take on a total of 20 climate-friendly eCitaro buses by summer. The electric buses – two solo and 18 articulated – will replace, among others, eight Citaro hybrids procured in 2011, which have run reliably in Dresden up to today. “In the OMNIplus Driver Training course, we show participants how the eCitaro works and what the essential differences are between it and a Citaro diesel. The driver should be able to fully utilise all the technical possibilities offered by an electric bus,” Jörg Spieß states.
But everything must be in the right order. It goes without saying that theory comes before practice. At the start of the course, Jörg Spieß from EvoBus greets the nine participants at the DVB training room on Dresden’s Tiergartenstraße, where the eCitaro will also later find a home. Spieß has been at the company since 1987 and is a trainer since 1999. His focus is on city buses. For two years, he has carried out training for the eCitaro. Spieß suggests that everyone gets on first-name terms from the beginning; a suggestion which is welcomed by all participants. Dropping formalities creates a sense of closeness between them and lightens the atmosphere. In a short presentation, Spieß then gives an introduction to the vehicle. One thing is palpable: the experienced bus drivers are open to, excited about and curious to get to grips with the new technology.
Going rapidly from the training room to the bus.
After the initial questions have been answered, Spieß doesn't hang around in the training room but takes the participants to meet the vehicle. Spieß: “a practical link is important and it is best to transfer knowledge about the electric bus with the eCitaro right in front of you.” The object under scrutiny is a 12-metre solo bus with a capacity of 75 passengers. This is already charged and waiting at the depot. Spieß starts the training content off from the back of the vehicle, looking at the battery packs situated at the rear. Then they circle round the entire bus. The topic of temperature and climate management in an eCitaro is fully explored.
“Detailed information about the electric bus is best given right next to the eCitaro itself.”
The optimum temperature for batteries is between 20 and 25 degrees.
Here, Spieß also underlines the importance of pre-conditioning, carried out in the eCitaro using the operational management system. “For economic reasons too, it is not advisable to set off from the depot with a cold vehicle,” Spieß notes. “This uses up excessive energy.” The optimum temperature for batteries is between 20 and 25 degrees. “The goal is to keep the battery cells at around 23 degrees so that they achieve optimum efficiency,” he underlines. This is important for optimising the range of the electric bus – something over which the driver has a lot of influence, as Spieß explains to the OMNIplus Training participants in Dresden.
Demanding topography and long return trips.
Optimum energy management has priority for DVB when deploying the eCitaro. “The articulated bus lines will have distances of between 300 to 450 kilometres,” explains Rico Seipel, head of e-mobility projects at Dresdner Verkehrsbetriebe. In Dresden, a combination of depot and intermediate charging will need to be used because of the demanding topography and the long routes. The electric buses are planned to run for 80,000 kilometres for year – “and we’ll make sure we achieve that too,” Seipel asserts.
“The electric buses are planned to run for 80,000 kilometres per year.”
It all comes down to the drag torque.
After instruction at the depot, the drivers are itching to hit the road in the eCitaro. The first driver steers the eCitaro out of the depot and filters into Dresden's city traffic. The electric bus hums quietly through the streets. “So, now we’ll let the eCitaro sail,” declares Jörg Spieß after a while. Sailing mode, into which the driver now switches, is a special feature of the eCitaro. By releasing the “gas”, the bus driver can cunningly make use of the low-level drag torque. Spieß: “Compared to a diesel, an electric bus only loses speed slowly. With a forward-looking driving style, a driver can thus save valuable energy.”
“With a forward-looking driving style, a driver can save valuable energy.”
Charging is a matter of a “click”.
How to charge the bus also needs explaining. For this reason, a stop is made en route at a so-called “MOBIpunkt”. At the e-charging columns, Spieß demonstrates intermediate charging. This is carried out via plug, with the trainer urging the drivers to keep their ears open: “listen to what happens!” A click indicates the mechanical locks have engaged. Then, Spieß points to the display showing how far the charging process has progressed. Later, the eCitaro is recharged en route using the roof-mounted pantographs. When charging is over, the plug is unclipped again. “Don’t pull it with any force,” the trainer insists. But no worries: during the charging process, we see that all participants have a very light touch. The OMNIplus trainer is satisfied. And in the bright sunshine, all return to the depot - naturally, in sailing mode again.
