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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 LiFePO 4 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.

The installation of energy recovery systems (ERSs) on-board diesel-electric mine haul trucks to capture energy when braking and re-inject stored energy on acceleration and ramp ascent, is proposed to reduce haul costs in surface mining. ERSs would add to equipment cost and reduce truck payload, reducing productivity and effectively increasing other haul-related costs. However, stored energy could reduce fuel consumption and could be used to reduce cycle time thereby improving productivity when conditions are favourable. This paper investigates how the installation of fixed size electro-mechanical flywheel (EMFW) or lithium iron phosphate (LiFePO 4 ) based ERSs could affect the overall cost of truck haulage over the 20-year life of a metalliferous surface mine reaching 600 m deep. The simulation study suggests LiFePO 4 technology can be expected to provide significantly greater haul cost reductions than the EMFW technology by reducing haul costs by 1.4-6.2% depending on the energy re-injection strategy employed.

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This thesis investigates the technical and economic feasibility, as well as emissions related benefits, of incorporating energy recovery systems (ERSs) on board mine haul trucks (MHTs) used in surface mining. More specifically it aims to answer the research question: "What practical combination of hybrid drive topology, and energy storage technology, capacity and use on board mine haul trucks, will maximise the economic benefit of energy recovery and re-use, considering variation in haul route characteristics and the time value of money through the life of a surface mining project?" To answer this question, a simulation program was developed and progressively expanded to conduct each of four main stages of the research. In Stage One, the simulation program was used to determine the potential of various technologies to reduce the fuel consumption per tonne mined for each of a range of pit depths. Appropriately informing the simulation program required identifying and quantifying representative input values for truck, haul route, and ERS characteristics. Truck and haul route characteristics determine the energy recovery rate and amount of energy recoverable to the trucks' DC-links. ERS characteristics enable evaluating the potential and practical implications of each ERS technology to capture this recovered energy. ERS technologies considered include ultra-capacitors, lithium-ion capacitors, chemical batteries, and electro-mechanical flywheels (EMFWs).