Trolley assist systems have seen renewed interest, with several major mines deploying or constructing new installations. Current setups use diesel-electric trucks but are being designed to support future battery trolley operations—such as Komatsu’s Power Agnostic 930E at Boliden Aitik, which is expected to operate on battery power by 2026. Caterpillar’s Dynamic Energy Transfer technology also supports both diesel-electric and battery-electric trucks.
While rigid trucks currently use trolleys, wide-body dump trucks—gaining popularity for their lower costs—are being considered for trolley operation. Zoomlion’s 70-ton ZT115DPEV, built on its electric ZT115EV model, has already undergone successful trolley trials in China. According to Zoomlion, limitations in battery energy density hinder wider adoption of electric trucks due to frequent charging needs, especially on routes without regenerative downhill braking.
The ZT115DPEV uses overhead power lines to supplement battery power, eliminating the need for frequent stops and enabling higher operational efficiency and range. Its design allows the truck to operate under trolley power and charge its battery simultaneously, switching to battery-only mode when off the line. With a dual-motor system and four-speed transmission, it achieves speeds over 15 km/h on continuous 10% grades, increasing productivity compared to traditional diesel or purely battery-powered vehicles.
Additionally, the ZT115DPEV’s narrower 4.2 m width and self-adjusting pantograph provide greater flexibility and maneuverability on mine ramps than larger rigid trolley trucks, supporting more efficient operations in varied mining environments.
