Techno-Economic Assessment of Integrated Upstream–Downstream Energy Systems for Decarbonized Mining Haulage

This study presents a techno-economic assessment of integrated upstream–downstream energy systems for open pit mining haulage using hydrogen-diesel dual fuel trucks and battery electric trucks over the period 2025–2050. Both pathways are modeled to deliver an equivalent payload for a representative large Australian mining operation with annual production of 20 Mt, under progressively tightening emissions constraints. Solar photovoltaics are assumed as the renewable energy source. For the hydrogen pathway, electricity is converted to hydrogen via proton exchange membrane electrolysis, followed by compression and pressurized storage, whereas the battery pathway stores electricity directly in lithium ion batteries. Component sizing is determined through hourly simulations and a cost minimization optimization that accounts for efficiency losses, degradation, replacement cycles, and operational reliability. The result shows that the optimized hydrogen upstream system requires a 14–22 MW AC/DC converter, a 13–21 MW electrolyzer, a 0.7 MW compressor, and 6–9 t of hydrogen storage, with annualized upstream costs increasing from approximately AU$4 million in 2025 to AU$6.5 million by 2050. The battery-based system requires an 8–9 MW AC/DC converter and a 43–45 MW battery, corresponding to energy capacity of 86–90 MWh at a 0.5C charge rate, with annualized upstream costs remaining near AU$6.3 million. When combined with downstream fleet costs, the hydrogen pathway consistently achieves lower total system costs than the battery electric alternative, primarily due to smaller fleet size requirements. Operational energy analysis shows that battery electric trucks draw a relatively steady 26–28 GWh/year of electricity, whereas downstream electrical demand for the hydrogen pathway increases from ≈3 GWh in 2025 to ≈40 GWh by 2050 as hydrogen progressively displaces diesel in the dual-fuel operation. While both systems meet annual emission compliance requirements, lifetime embodied energy differs. The hydrogen-based system exhibits lower embodied energy, stemming from a smaller required fleet and lower embodied-energy intensity of the upstream infrastructure than the battery–electric system. Sensitivity analyses confirm the robustness of these findings.