Simulating diesel and battery-electric haulage in underground mines: productivity, heat load, and energy usage

Battery-electric vehicles can improve ambient conditions in underground mines by reducing the amount of heat and diesel exhaust produced during the execution of mining activities (e.g., hauling fragmented rock). Literature comparing diesel- and battery-powered vehicles considers differences in cost, productivity, and heat load between individual vehicles or one type of vehicle (e.g., only trucks or only loaders); this paper determines the effect of electrifying an entire haulage fleet on the productivity, heat load, energy usage, and emissions of an underground mine using discrete-event simulation. Battery-electric loaders and haul trucks reduce heat load by 76 to 82%, CO2 emissions by 39 to 48%, and energy cost by 50 to 57%, while the amount of material extracted is 90 to 105% that of an equivalent diesel fleet. A further evaluation of the trade-offs between fast charging and battery swapping finds that fast charging results in more than twice the peak power consumption relative to battery swapping, and that recharging equipment contributes an additional heat load of up to 26% compared to vehicle operation alone. This information is important as mine operators assess vehicle electrification as a means to achieve greenhouse gas emissions reduction targets and safer mine environments.