As near-surface deposits deplete and global demand for mineral resources soars, the mining industry faces the dual challenge of maximising resource extraction while optimising operational efficiency. The adoption of electrically powered haulage solutions presents a potential alternative to conventional diesel-powered trucks, but this transition is highly capital-intensive, requiring reliable data insights to assess feasibility. This study employs stochastic Discrete Event Simulations (DES) to evaluate the operational, energy efficiency, and economic impacts of replacing diesel-powered haul trucks with battery-electric haul trucks in an open pit mining operation in the USA. The simulation model, validated to within 5 per cent of operational data, reveals that transitioning to battery-electric haul trucks reduces productivity by up to 23 per cent. Despite this decline, the shift significantly improves energy efficiency, with potential reductions in fuel costs and overall energy expenditures by approximately 34 per cent. These findings provide critical insights into the trade-offs between productivity and cost efficiency, supporting data-driven decision-making for mining operations.