Epsilon Open Archive

This report is a pre-study of factors influencing Hybridisation of non-road mobile machinery. The study has included incentives and constraints for hybridisation and an overview of the current state of research and development in the area as well as the commercialization of
hybrid vehicles.

Non-road hybrid vehicles have to some extent the same advantages and disadvantages as hybrid road vehicles, such as reduced fuel consumption and reduced emissions at the expense of increased manufacturing costs. However, there are also differences. Concerning technical aspects important benefits of hybridisation specific to non-road vehicles include high torque at low speeds and increased controllability, while on the other hand the environment is
tougher for electric components. The economic competitiveness of non-road hybrids is positively affected by the increased productivity originating from the higher torque at low speeds, while the possibility of green PR is limited is comparison with road vehicles.

With the exception of some minor sectors (such as forklifts) hybrid non-road mobile machinery are in an introductory phase. Many different types of topographies (serial, parallel), storage devices (batteries, super capacitors) and control strategies are tested and few
clear-cut trends exist for these factors. However, it is quite clear which parts of the vehicles that are the focus for hybridisation. For excavators, it is the rotation of the upper body that is hybridised, while for wheel loaders it is the wheel drivetrain that is the focus of hybridisation. Information on how much fuel consumption can be reduced varies considerably between different research groups and manufacturers, corresponding to variation in degree of hybridisation, duty cycle etc. Development of vehicles powered by fuel cells take place in the forklift sector, but is otherwise limited to concept vehicles.