Heavy mining equipment relies on specialized electrical power transmission systems, primarily overhead trolley lines and trailing cables. Overhead trolley systems, like ABB’s eMine™ Trolley, electrify haul trucks, allowing them to draw power from overhead lines.
This significantly reduces diesel consumption (up to 90%) and enables higher speeds on inclines, which battery-only solutions may not achieve. These systems are modular and can be relocated (ABB, n.d.).
Trailing cables are robust, flexible, high-voltage cables designed to power large mobile equipment such as draglines and shovels. They are constructed with durable insulation (rubber, TPE, XLPE) to withstand harsh underground conditions like abrasion, vibration, and moisture (Greater Wire, n.d.).
Power is supplied from surface substations, which transform high-voltage grid power (up to 25KV) down to appropriate underground transmission and utilization voltages (e.g., 4160V, 995V) via underground substations and Mine Load Centers (IE Corp, n.d.).
Strict MSHA regulations govern electrical safety, mandating proper grounding of equipment frames and continuous ground check monitoring for trailing cables to prevent shock hazards (MSHA, n.d.).
Corrosion protection, using materials like PVC-coated conduits and vapor corrosion inhibitors, is also crucial for electrical infrastructure longevity in the harsh mine environment (Zerust, 2025).
Why do you think mines still use trailing cables and overhead lines instead of relying only on batteries? Share your thoughts!


