Electric Power Conversion Australia (EPCA), a Perth, Western Australia-based company, is gaining attention for its advancements in electrifying heavy machinery, with its biggest project to date, a fully retrofitted Caterpillar 777 haul truck operating entirely on battery power, taking another step towards becoming a commercial proposition.
Founded by Clayton Franklin, who also leads its engineering team as Chief Engineer, the company plans to retrofit up to 70 trucks annually from diesel to battery-electric.
Having initially showcased this vehicle at The Electric Mine 2024, in Perth, in May, followed by an appearance in Kalgoorlie at Diggers and Dealers, the company has now progressed to trial operations.
At Bakers Hill, a sand mine located just 40 minutes north of Perth, EPCA’s fully battery-electric 91 t haulage truck has been hard at work for the past month. This test phase marks a significant step forward for the company, demonstrating EPCA’s commitment to sustainability, efficiency and innovation while enhancing operational efficiency and cutting costs, the company says.
The retrofit of the CAT 777 represents a complete overhaul, not just a minor upgrade. The diesel engine has been entirely replaced with an electric motor powered by high-capacity batteries (supplied by Xerotech), marking a radical shift in the truck’s operation. More than 5.9 t of components were removed and replaced by six batteries, each weighing 1.4 t. In the end, the truck is now 2.5 t lighter, thanks to the reduced weight of the custom-designed tray made by Austin Engineering, EPCA says.
This transformation offers far more than environmental benefits; it significantly enhances efficiency and operational viability, the company explains. Additionally, the electric truck is expected to reduce maintenance and operational costs for mining companies compared with the diesel equivalent, providing a cleaner, more cost-effective alternative to traditional diesel-powered trucks. EPCA assures that, over 20 years, the total cost of ownership for a diesel truck will be approximately A$25 million ($17 million), while the battery-electric truck’s total will come in at A$11.5 million.
Performance data and results
Bakers Hill, a privately held sand mine, provides the perfect environment for EPCA to push the limits of its technology, according to the company. The eastern side of the mine was prepared for testing, with a grader pushing up a ramp featuring a 17% incline and a turnback. Though it is a sand mine, the conditions and setup at Bakers Hill are comparable to a bauxite mine in terms of depth and incline, offering a realistic representation of the challenges this truck might face at commercial-scale mining operations.
In these conditions, the electric truck has shown impressive performance metrics, according to EPCA. During standard operations, the truck has consistently delivered over 10 hours of runtime on a single charge, with the battery taking just 50 minutes to fully recharge. This quick turnaround time ensures that the truck can maintain its productivity, minimising downtime while still offering substantial energy savings.
One of the key tests involved driving the truck on a 17% incline, where it consumed 252 kWh of energy. On the descent, the regenerative braking system was able to recover 35 kWh (15%). When stationary, with the auxiliary systems running, the truck consumes around 20 kWh/h.
The truck is designed for 91-t payloads, with the testing at Bakers Hill revealing that it can handle inclines of up to 27% under full load. This makes it an ideal candidate for some of the most challenging mining operations where steep inclines and heavy loads are standard, EPCA says.
Scalable fast-charging solution
Delivering charging infrastructure on mine sites is challenging. Mining companies are forced to deploy large and expensive infrastructure to be able to charge large electric fleets. EPCA has collaborated with Western Australia-based integrated energy solution provider UON Pty Ltd, who has developed the SMART™ (Scalable, Modular, Automated, Renewable, Temperature controlled) CELL DC Fast Charging solution, which can charge the CAT 777 haul truck in less than 50 minutes, according to the company. The UON charging solution has been designed to operate in harsh Western Australian mining conditions, ensuring reliable charging power at all times.
The UON SMART DC Fast Charging can be seamlessly connected to the existing grid or be powered completely by 100% renewable energy, such as solar, providing much-needed charging infrastructure in grid-constrained locations, the company says. Its all-in-one mobile Battery EV charging solution is fully mine-compliant and can be easily redeployed on any brownfield or greenfield mine, which enables mining companies to avoid a large investment in infrastructure, UON says.
Real-world demonstrations and future steps
EPCA has already showcased the truck at Bakers Hill to several Tier-One mining companies, all of whom have expressed very positive reactions, according to EPCA. “These real-world demonstrations are designed to showcase the truck’s capabilities and the benefits of electrification in reducing carbon emissions and operational costs,” it says.
Following the Bakers Hill trials, EPCA plans to move into endurance testing in 2025 and run this design for many thousands of hours before moving into mass production.
The company concluded: “EPCA is well positioned to meet the increasing demand for battery-electric mining trucks. Supported by a robust distribution network, the company is set to fulfil its order book of over 600 trucks, reinforcing its leadership in the electrification of the mining industry.
“The future of mining is electric, and EPCA’s work is leading the way in making that a reality.”