At the IAA Transportation 2022 show in Hanover, Mercedes-Benz Trucks reiterated it would expand its range of vehicles to include volume production trucks with hydrogen fuel cell drivetrains in the second half of the 2020s.
“Hydrogen-based drives can be the better solution especially for flexible and demanding applications in the important segment of heavy-duty transport and long-haul applications,” the company said.
“For electric trucks, the same as for conventional trucks applies. When choosing their vehicles, transport companies make rational purchasing decisions based on total cost of ownership.”
Further reasons to rely on a second zero-emission drive technology are the availability of a corresponding infrastructure and the availability of sufficient green energy. The truck maker said this energy requirement can only be covered quickly and cost effectively with green electricity and green hydrogen.
“Hardly any country in the world will be able to supply itself with green energy alone at competitive prices in the future. Consequently, there will have to be global trade with CO2-neutral energy sources.”
‘Green’ hydrogen would play a central role here and it assumes it will be “traded at very attractive prices in the future”.
The truck manufacturer also sees costs advantages and technical feasibility of the hydrogen infrastructure, as well as longer ranges, flexibility and shorter refueling times for customers.
“Therefore, hydrogen trucks can be a viable option for our customers, especially in tough long-haul operations and notably in terms of total cost of ownership.”
Development in progress
The first second generatrion hydrogen fuel cell prototypes have been undergoing testing since last year both on the in-house test track and on public roads.
Mercedes-Benz said it prefers liquid hydrogen as, in this aggregate state the ‘energy carrier’ has a significantly higher energy density versus volume compared to gaseous hydrogen. More can be carried which significantly increases the range and enables comparable performance of the vehicle with that of a conventional diesel truck.
The development objective for production is a range of 1,000 kilometres (600 miles) which makes the truck suitable for particularly flexible and demanding applications, especially in the important segment of heavy duty, long haul transport.
The GenH2 Truck is based on the conventional -Benz Actros long-haul truck in terms of payload, range and performance. The aim is to offer the series-produced H2 with a payload of 25 tonnes at a gross weight of 40 tonnes. Two special liquid hydrogen tanks and a particularly powerful fuel-cell system will enable this high payload and long range. The two stainless steel liquid-hydrogen tanks will have a particularly high storage capacity of 80kg for covering long distances. The tank system consists of two tubes, one within the other, that are connected to each other and vacuum insulated.
The fuel cell system will supply 2 x150 kilowatts and the battery an additional 400 kW temporarily. At 70 kWh, the storage capacity of the battery is relatively low, as it is not intended to meet energy needs, but mainly to be switched on to provide situational power support for the fuel-cell, for example during peak loads while accelerating or while driving uphill fully loaded. At the same time, the relatively light battery allows a higher payload. It will be recharged with braking energy and excess fuel cell output.
A core element of the fuel cell and battery system is a cooling and heating system that keeps all components at the ideal operating temperature, thus ensuring maximum durability. In a pre-series developemtn version, the two electric motors are designed for a total of 2 x 230 kW continuous power and 2 x 330 kW maximum power. Torque is 2 x 1577 Nm and 2 x 2071 Nm respectively.
Daimler Truck is also working with Linde on the development of a new process for handling liquid hydrogen (subcooled liquid hydrogen, sLH2 technology) which enables even higher storage density and easier refuelling compared to LH2. The companies plan for the first refuelling of a prototype vehicle at a pilot station in Germany in 2023. The goal is to collaborate with other companies and associations to develop their own refuelling and vehicle technology which uses the new liquid-hydrogen standard and establishes a global mass market for the new process.
An infrastructure for hydrogen filling stations along important transport routes in Europe will be essential so Daimler Truck is planning to work with Shell, BP and TotalEnergies and is also a shareholder in hydrogen filling station operator H2 Mobility Deutschland.
Separately, Daimler Truck, Iveco, Linde, OMV, Shell, TotalEnergies and Volvo Group have committed to work together to help create the conditions for the mass-market roll-out of hydrogen trucks in Europe as part of the H2Accelerate (H2A) interest group.
Fuel cell joint venture
Volvo Group and Daimler Truck companies founded a joint venture call cellcentric in 2021which plans to become one of the world’s leading manufacturers of fuel cell systems. It will set up series production facilities in Europe starting in 2025.