BHP is preparing to trial Caterpillar’s Dynamic Energy Transfer (DET) system at its Jimblebar iron ore operation in Western Australia’s Pilbara region during the 2027 financial year (FY27), as it investigates ways to electrify its haul truck fleet without compromising productivity.
During a recent environmental, social and governance roundtable, BHP highlighted the potential productivity impact of static charging. Its modelling estimates that a battery-electric haul truck could lose approximately 1,000 operating hours annually compared with a diesel-powered equivalent if charging requires multiple stops throughout the day.
According to BHP’s September 16 presentation, the estimate is based on a theoretical, pre-commercial 220-tonne-class battery-electric truck equipped with a three-megawatt-hour battery. The model assumes six to eight static charging stops of approximately 30 minutes each over 24 hours, compared with a single 15-minute refuelling stop for a diesel truck. Actual charging requirements will depend on haul cycles and energy consumption.
The 1,000-hour figure is a modelling estimate rather than downtime recorded during BHP’s existing trials. However, it highlights a significant challenge facing mining companies seeking to reduce diesel consumption while maintaining material movement and operational efficiency.
Caterpillar’s DET technology is designed to supply electricity to electric-drive haul trucks while they are moving around a mine site. For battery-electric trucks, the system could enable charging during operation, reducing the need to remove vehicles from the haul cycle for extended periods.
BHP is assessing how dynamic charging could be combined with conventional static charging and integrated with autonomous haulage systems. The company aims to determine whether these technologies can work together to support the operational demands of large-scale mining.
The miner has already commenced proof-of-concept trials involving two battery-electric haul trucks on a dedicated test track at Jimblebar. The trials are evaluating vehicle range, energy consumption, battery performance, charging efficiency, reliability, safety and overall productivity.
The DET program will expand this work, with BHP also planning to commission high-power static charging infrastructure at Jimblebar during FY27. Findings from these initiatives will help the company assess whether battery-electric haulage can meet the requirements of a continuously operating iron ore mine.
BHP and Caterpillar first announced plans to trial the technology in 2024, including testing with Cat 793 trucks at Jimblebar and Cat 798 trucks at Escondida in Chile. The latest assessment highlights the importance of maintaining productivity as mining operations transition towards electric-powered equipment.
Beyond the trucks and charging systems, successful deployment will require coordinated investment in electricity supply and supporting infrastructure. BHP has indicated that investments will be staged as equipment and technologies mature. For remote mining operations, sufficient power capacity and reliable electricity supply will also be critical considerations.
The company continues to identify battery-electric equipment as its preferred long-term pathway for reducing diesel use, while considering renewable diesel, hybrid trucks and other technologies for applications where they may be more suitable.
Safety remains another priority as mining fleets become increasingly electrified. BHP has identified potential hazards associated with high-voltage systems, direct-current arc flash and batteries. The company is working with equipment manufacturers to develop appropriate controls and validate safety measures before broader deployment.
The planned trials at Jimblebar will help establish how electric haul trucks, charging infrastructure, power systems and existing mining operations can be integrated effectively. Their results will be important in determining whether dynamic charging can reduce interruptions to the haul cycle and support the productivity levels required for large-scale iron ore mining.