Daimler Trucks is focusing on hydrogen-powered fuel-cells for the electrification of its vehicles for flexible and demanding long-haul transport, aiming to achieve ranges of up to 1,000 km and more without any stops for refuelling.
In late April, the truck manufacturer began to conduct rigorous tests of the first newly enhanced prototype of its Mercedes-Benz GenH2 Truck, which was unveiled in 2020. This marks an important milestone on the path to series production.
The extensive series of tests is very demanding for the vehicle and its components, and focusses, among other things, on continuous operation, different weather and road conditions, and various driving manoeuvres.
According to Daimler Trucks’ development plan, the vehicle will also be tested on public roads before the end of the year. While customer trials are scheduled to begin in 2023, the first series-produced GenH2 Trucks are expected to be handed over to customers starting in 2027.
Martin Daum, Chairman of the Board of Management, Daimler Truck AG and Member of the Board of Management, Daimler AG said, “We are consistently pursuing our technology strategy for the electrification of our trucks. We want to offer our customers the best locally CO2-neutral trucks — powered by either batteries or hydrogen-based fuel-cells, depending on the use case. We’re right on schedule and I’m delighted that the rigorous tests of the GenH2 Truck have started successfully.”
The hydrogen-powered fuel-cell drive will become indispensable for CO2-neutral long-haul road transport in the future, Daum added. This is also confirmed by Daimler’s many partners with whom it is working together at full steam to put this technology on the road in series-production vehicles.
“Moreover, considerable momentum is being generated by the clear commitment of national and European regulators to the use of hydrogen for road freight transport. Political support plays an important role in promoting the creation of an infrastructure for green hydrogen and making an economically viable use of fuel-cell trucks possible for our customers,” he said.
Demanding Tests
The GenH2 truck is being designed to ensure the vehicle and its components meet the same durability requirements as a comparable conventional Mercedes-Benz Actros. This would mean that over a 10 year period, the truck would need to be tested over 1.2 mn km on the road in over 25,000 hours of operation.
Daimler said the vehicle, in the first few weeks of testing, has already covered hundreds of kilometres under continuous load on a road-to-rig test stand. It has undergone extreme situations that are based on real-life operating conditions.
New Concept, New Components
The GenH2 truck has been newly designed, and features completely new components as well, including the fuel-cell system, the all-electric powertrain, and all associated systems like the special cooling unit.
The new components’ specific weight and position in the vehicle affect the truck’s handling properties, which results in vibrations caused by bumpy roads, for example.
During the tests, Daimler loaded the current prototype with a payload of up to 25 tonne for a gross vehicle weight of about 40 tonne. This is identical with the specifications planned for the series-produced variant of the GenH2 Truck.
What Are The Advantages Of Liquid Hydrogen?
Hydrogen in its liquid form has a far higher energy density in relation to volume than gaseous hydrogen. As a result, the tanks of a fuel-cell truck using liquid hydrogen are much smaller and, due to the lower pressure, significantly lighter. This gives the trucks more cargo space and a higher payload.
Carrying more hydrogen significantly increases the trucks’ range. This makes the series GenH2 Truck, like conventional diesel trucks, suitable for multi-day, difficult-to-plan long-haul transport and where the daily energy throughput is high, the company claims.
On the basis of a predefined development plan, Daimler Trucks is also forging ahead with the development of tank technologies for liquid hydrogen. The new prototype tank system is expected to become sufficiently mature by the end of the year to be used for the on-going tests.
The vehicle tests will then be conducted exclusively with liquid hydrogen tank systems until the series-production stage is reached. Until this can be done, the extensive internal testing of the GenH2 Truck will use a gaseous hydrogen tank system as an interim solution.
Daimler Trucks is thus demonstrating that both variants – gaseous and liquid – can be technically implemented.