Stefan Kalt looks pleased. The director of RVBW, the Baden-Wettingen regional transport services (Regionalen Verkehrsbetriebe Baden-Wettingen), stands casually in the depot chatting to his guests. An eCitaro electric bus is currently charging behind him. The temperature is frosty but the sun is shining over Wettingen on this December day – perfect for the festive occasion.

The all-electric Mercedes-Benz city bus at the RVBW depot is part of a mega project that Daimler Buses has been intensively preparing, developing and implementing for the Swiss transport operator since March 2022 in collaboration with expert partners. What makes it special is that Daimler Buses is not only supplying ten eCitaro Solo buses, they also acted as the general contractor responsible for the complete eMobility system, including charging infrastructure, charging management and structural alterations.

Today is the day of the final acceptance inspection at RVBW and all project participants are attending. “We are really impressed with how everyone has worked towards this joint success” says Stefan Kalt and calls the undertaking an “extremely important project for RVBW”.

“The RVBW project is actually a real milestone for the transition to electric mobility in Switzerland”, explains Marcel Wolf. The tender manager from Daimler Buses Switzerland acted as the central coordinator. As manager of the RVBW project, Wolf coordinated cooperation between charger manufacturers and charging management providers. Or as Marcel Wolf puts it: “one project partner called the shots”.

Coordination is a word mentioned frequently on this special day. But how well did it actually work in practice? Wolf acted as the central point of contact for all areas of this complete e-mobility system on behalf of RVBW. The advantage: the transport operator did not have to contact various service providers individually if they had any questions – instead it took just a single phone call.

And there were plenty of questions during the course of the project, as Werner Fischer, Head of Technology at RVBW, can tell us. The Baden-Wettingen regional transport operator had to overcome a whole raft of specific challenges.

Fischer laughs and explains that they have learned very well what the abbreviation SCR stands for during the course of their intensive cooperation with Daimler Buses: special customer request. “I was impressed by how Daimler Buses responded to individual requirements and overcame any challenges with great professionalism” says Fischer in admiration, “especially given the large number of people involved in this project”.

After all, not all participants were always present on site and had to be involved digitally. In total, up to 20 people were involved in the project and their cooperation was managed by Daimler Buses.

RVBW has opted for a depot charging strategy. The charging infrastructure required was supplied by Swiss provider Furrer+Frey. The electric buses are charged by high-performance busbars on the vehicles combined with top-down pantographs. Werner Fischer points up to where the technology made by Furrer+Frey can be clearly seen under the roof of the depot.

“Pantograph charging has many advantages”, explains Mathis Noisternig, the responsible project manager at Furrer+Frey. "All the electronics are integrated in one device. This saves space and keeps everything looking clean and tidy." And this technology makes it considerably easier for drivers to start the charging process. They simply have to push a button and there is no need to insert a bulky plug.

Communication between the vehicle and the control centre is managed entirely by a secure network. Vehicle data is stored in a secure cloud. This is where the software provider for load and charging management comes into play. In the case of RVBW, this is IVU Traffic Technologies – an established e-mobility partner of Daimler Buses.

“Working with Daimler Buses, we implemented a technical solution for preconditioning at RVBW that is the first of its kind in the world”, explains Matthias Feldmann, project engineer at IVU Traffic Technologies Switzerland. A substitute interface from OMNIplus ON sends the preconditioning command from IVU directly to the vehicle. Feldmann stands by the driver’s cockpit of the eCitaro and points to the display, which shows the current state of charge.

Wi-Fi communication between the bus and charging infrastructure has many advantages, but can also be tricky due to a host of interference factors. Therefore, RFID tags were installed in vehicles as a practical solution. “This prevents a bus on the left carriageway from connecting to the pantograph on the right carriageway, which would cause a dangerous situation”, explains Wolf.

As the eCitaro finally drives with a quiet hum out of the depot and into the sunny courtyard with its batteries fully charged, the moment has something almost magical about it. But the path to successful completion of the project was anything but witchcraft. The run-up to the launch involved exhaustive testing and analysis of possible problems to ensure that everything would run smoothly in RVBW's day-to-day operations.

“In the summer of 2023, we conducted two weeks of intensive testing using our demonstration vehicle and a vehicle from a third-party customer”, explains Marcel Wolf. The tests were carried out in accordance with the OppCharge data communication standard, which ensures smooth communication between vehicles and chargers. The standardised application protocol OCPP (Open Charge Point Protocol) is used for data communication between the charger and IVU's backend. “We optimised every aspect until everything was perfect”, recalls Matthias Feldmann.

“This project is packed with expertise”, confirms RVBW Director Stefan Kalt, as he invites all guests to board the cosily preconditioned bus for the inaugural trip. And, as if in agreement, the sun continues to beam down from the Swiss sky as the eCitaro glides up the road to the hills of Wettingen.