A trolley system using overhead lines was tested at an iron ore mine in Austria. The system allows for switchbacks. (Photo: Liebherr)

Part of an effort to cut fuel burn and emissions, miner VA Erzberg GmbH and Liebherr tested a trolley-assist system for T 236 diesel-electric haul trucks at the Erzberg iron ore mine near Eisenerz, Austria. The $23.5 million project hopes to prove unique purpose-built technologies.

For the tests, a truck was modified to operate with an overhead line connected through a current collector on a 500-m-long uphill-haulage test track. The arrangement, differing from conventional pantograph systems, allows for small radii and switchbacks, and for better usage of the haul road.

When in trolley mode, the full power capacity of the electric wheel motors can go to building speed while the diesel engine idles. This cuts fuel consumption and emissions, two goals of the project.

The miner reported it burns 4.5 million liters per year of diesel to transport more than 13 million metric tons per year (mt/y) of rock. That figure could be reduced by 3 million liters if the new system performs as planned, the mine reported.

“In addition to the positive environmental effects, an investment in this new technology also secures the sustainable extraction of iron ore for domestic steel production,” said Josef Pappenreiter, technical director, VA Erzberg.

At the end of September, the trolley line was extended to 5 km. The miner will now track how Alpine winter weather affects the overhead lines and the performance of six T 236 trucks.