HZwo: HyWheelTank
Integration and Testing of a Wheel-Integrated Energy Storage Solution for Heavy Mobile Machinery: The Case of a Wheel Loader
| Funding: | European Regional Development Fund (ERDF), Development Bank of Saxony (SAB) |
| Grant ID: | 100807190 |
| Partners: |
Hörmann Vehicle Engineering GmbH (consortium leader) |
| Duration: | June 2026 – October 2028 |
| Contact: |
Motivation
The use of hydrogen as an energy source for heavy construction machinery is becoming increasingly important in light of the need for decarbonization and the achievement of climate goals. A technological shift toward low-emission propulsion concepts therefore offers significant potential for reducing emissions. Hydrogen-based propulsion systems for wheel loaders, dump trucks, and excavators represent a promising alternative in this regard. Leading machinery manufacturers are already actively pursuing various technological paths.
Challenge
A key technical challenge—one that has not yet been adequately resolved—for the widespread adoption of this technology lies in integrating the necessary hydrogen storage capacity into the machine. With currently available storage technologies, it has not yet been possible to achieve anywhere near the same operating time as with conventional diesel-powered machines. However, long and, as far as possible, uninterrupted operating times are an essential prerequisite for economical and practical construction site operations. A major reason for this is the low volumetric energy density of gaseous hydrogen compared to diesel. The high-pressure storage tanks required for this have correspondingly large dimensions and can only be integrated to a limited extent into the existing, already severely constrained installation spaces of modern construction machinery. To nevertheless integrate the required storage capacity into existing vehicle structures, novel storage concepts and approaches for creating additional installation space are therefore necessary.
Technical Approach
One promising approach involves ring-shaped hydrogen pressure storage tanks, which can be integrated into existing structural elements—such as the wheel or rim structure—particularly in mobile construction machinery. This allows previously unused installation space to be utilized for hydrogen storage without increasing the machine’s external dimensions. This enables an increase in the total available storage volume and thus contributes to extending the operating life and improving the cost-effectiveness of hydrogen-powered mobile machinery.
Konzeptentwurf zur Integration ringförmiger Wasserstoffdruckspeicher in einen Radlader.
However, modifying the existing wheel structure with the innovative H₂ storage system affects the traction, vibration, and wheel-to-ground behavior of mobile construction machinery. As part of the subproject led by the Chair of Construction Machinery, the effects on traction, rolling resistance, and ride comfort are quantitatively investigated and evaluated using simulation models. In addition, a parameter influence analysis is being conducted to examine the concept’s applicability to other machine classes. At the same time, the newly developed H₂ storage solution is being integrated into a 24-metric-ton wheel loader and validated under real-world operating conditions.