Techno-econo-environmental comparisons of zero- and low-emission heavy-duty trucks

This paper presents the results of techno-econo-environmental modelling of options to decarbonise fleets of four-axle trucks in the quarrying sector. The key parameter used to evaluate the performance of transitioning from diesel heavy-duty trucks (HDT) to zero- or low-emission heavy-duty trucks (ZLETs) is the total cost of carbon abatement (TCA). TCA is calculated by using the total cost of truck ownership on a discounted cost per km basis (TCO) and well-to-wheel (WTW) life-cycle greenhouse gas (GHG) emissions. TCO includes the costs of the vehicle, infrastructure, fuel, maintenance, and resale, and is evaluated for five different powertrain configurations: (1) battery electric heavy-duty truck (BET), (2) plug-in hybrid electric heavy-duty truck (PHET), (3) diesel internal combustion engine heavy-duty truck (ICET), (4) diesel-hydrogen dual-fuel engine heavy-duty truck (DFET), and (5) hydrogen fuel cell electric heavy-duty truck (FCET). Combinations of wind and/or grid electricity supply BETs and PHETs. Hydrogen is also produced from the same energy sources via electrolysis for DFETs and FCETs. The hourly electricity and hydrogen production and refuelling performance for each powertrain are assessed for on- and off-grid systems. The production capacity and costs can be optimally sized using the total number of trucks, annual operational distance, and fuel economy to meet the annual fuel demand for each powertrain. Results show the fuel cost is the largest contributor to TCOs for all powertrains except the BET, which is dominated by infrastructure cost. The TCOs for all powertrains in off-grid system are higher compared to on-grid systems, which require smaller equipment sizes. In contrast, more WTW emissions for all powertrains can be abated by off-grid system compared to on-grid system. The minimum TCAs for fleets of 100 trucks in on- and off-grid systems are found for BETs and DFETs, respectively. The total number of trucks has a significant impact on the reduction of TCO and TCA. Higher carbon tax (€/ tonne of CO₂ emitted) in the future can also help the ZLETs to be more competitive.