Potential of on-board energy recovery systems to reduce the costs of diesel–electric mine truck haulage

Abstract

On-board energy recovery systems (ERSs) are expected to reduce fuel consumption of open-pit mine haul trucks. However, the additional mass of an ERS would reduce the truck's payload, hence reducing productivity, effectively increasing other haul-related costs. Using a simulation program incorporating appropriate models for a diesel-electric mine haul truck, capital costs, operating costs and four energy recovery technologies, this paper investigates how various ERS technologies would affect overall haulage cost. Two energy re-use strategies are considered. The power augmentation strategy, which aims to reduce cycle times, promises greater savings than the fuel replacement strategy, which reduces engine power using recovered power. The ERS technologies found to be best suited to the application are fast charging LiFePO₄ batteries, and electro-mechanical flywheels. Using the power augmentation strategy, the potential cost reduction for both technologies under ideal conditions is 7%. Restrictions on exploiting the full potential of ERS systems are highlighted and discussed.