
In discussions regarding electric vehicles, the argument is often heard that electric drives have to surrender to internal combustion drives when it comes to output power. That is a myth, as is proved by giant electrically driven mining trucks of 3,000 hp.
These trucks are used in mines throughout the world. They convert power from a diesel engine into electricity, which is then used in an electric drive system. The main reason for this energetic detour is to ease braking and speed regulation. Using an internal combustion engine for such a powerful truck would require an enormous gearbox and a complex braking system, involving a considerable amount of maintenance.
Siemens recently developed a new technology for improving the performance of this kind of electric vehicle: trolley trucks.
The trolley mining trucks function like streetcars, using pantographs that connect to catenaries. This enables the doubling of the power output from the usual 3,000 hp to 6,000 hp. Such a high power is especially useful on steep mining slopes. The system makes use of grid electricity instead of a diesel engine, which significantly increases the environmental performance and reduces the energy cost.
Thanks to the improved operational performance and the lowered energy cost, the trolley installation is paid back in three years. The trolley system also allows for connecting the trucks to nearby renewable energy generation units.