Mercedes-Benz has recently delivered the first three of 48 fully electric eCitaro articulated buses with a 60 kW fuel cell as a range extender to Rhein-Neckar-Verkehr GmbH (rnv), a public transport operator in the Rhine-Neckar region of Germany. These buses are the world’s first series-production vehicles of their kind, and they offer a range of up to 400 kilometers on one charge, making them ideal for urban traffic.
What are fuel cell buses, and how do they work?
Fuel cell buses are buses that use hydrogen as a fuel source to generate electricity for propulsion. Unlike battery-electric buses, which rely on rechargeable batteries, fuel cell buses can run on hydrogen for longer distances without needing to be plugged in. The only by-product of fuel cell operation is water vapor, which means that fuel cell buses have zero tailpipe emissions and can reduce local air pollution.
Fuel cells consist of two main components: an electrochemical cell that converts hydrogen and oxygen into electricity and water and a heat exchanger that transfers the heat from the reaction to a cooling system. The electricity produced by the fuel cell powers an electric motor that drives the wheels of the bus. The hydrogen is stored in high-pressure tanks or cylinders on board the bus, and it can be refueled at dedicated hydrogen stations along the route.
What are the benefits of eCitaro G fuel cell buses?
The Mercedes-Benz eCitaro G fuel cell buses are based on the eCitaro solo bus, introduced in 2019 as a battery-electric city bus with a range of up to 200 kilometers. The eCitaro G adds a 60 kW fuel cell as a range extender, increasing the range to 400 kilometers on one charge. This means that rnv can operate its fleet of 48 eCitaro G buses for up to four days without refueling.
The eCitaro G also offers several advantages over battery-electric buses, such as:
- Faster refueling time: The hydrogen tanks can be filled up in about five minutes at standard hydrogen stations, compared to several hours at battery-electric charging stations.
- Higher efficiency: The fuel cell has an efficiency of about 60%, compared to about 80% for battery-electric motors.
- Lower weight: The fuel cell adds only about 100 kg of weight to the bus, compared to about 500 kg for batteries.
- Higher reliability: The fuel cell has fewer moving parts than batteries, which reduces the risk of failure and maintenance costs.
How does rnv plan to use its eCitaro G fleet?
rnv has set itself an ambitious goal of converting its entire vehicle fleet in Mannheim-Ludwigshafen-Heidelberg metropolitan area to locally emission-free drives by 2032. To achieve this goal, rnv has ordered 48 eCitaro G fuel cell articulated buses from Daimler Buses by mid-2025. Of these, 40 will be used for regular service in Mannheim and Heidelberg, while eight will be used in Ludwigshafen am Rhein.
The rnv depot at Bergheimer Strasse 155 in Heidelberg will serve as one of the main hubs for storing and refueling the hydrogen tanks. rnv has also partnered with H2Rhein-Neckar and H2Rivers projects, which aim to develop hydrogen infrastructure along major transport corridors in Germany. By using these projects’ facilities and networks, rnv hopes to reduce its operational costs and increase its flexibility.
In addition, rnv has an order option for an additional 27 eCitaro G fuel cell articulated buses by mid-2027 if required. This would bring its total number of locally emission-free vehicles provided by Daimler Buses. rnv is not only committed to reducing its environmental impact but also improving its customer experience. By using locally emission-free vehicles that offer high performance and reliability, rnv aims to provide more comfortable and convenient travel options for its passengers.
The Mercedes-Benz eCitaro G fuel cell buses are a breakthrough innovation that demonstrates how sustainable urban transport can be achieved with hydrogen technology. By using these vehicles, rnv sets an important standard for increasing environmental friendliness in local public transport within Germany’s Rhine-Neckar region.