To account for uncertainty and variability in existing datapoints, the model assumptions (that could change depending on regional and operational dynamics) and future cost trajectories, a scenario and sensitivity analysis was also undertaken. Geographical factors, market dynamics and operational needs can affect the assumptions used for the analysis, requiring flexibility in the assessment performed. This sensitivity analysis thus aimed to identify the key variables influencing the levelized cost of ownership (LCO, €/km) for each bus technology scenario: diesel, retrofitted, battery electric and hydrogen (see Figure 7). Certain variables, such as bus driver salary, utilization rate and government subsidies, are significant drivers of cost across all technologies. Driver salary, in particular, represents a substantial share of operational expenditure. Utilization rate – defined as the proportion of time a bus is actively in service carrying passengers – directly impacts the amortization of fixed costs and is a key determinant of LCO for all scenarios. The longer a bus is in service carrying passengers, the more its fixed costs are spread out, lowering the overall cost per km. Conversely, if buses are used less, the cost per km can rise dramatically, sometimes by as much as 300% for some of the technology scenarios.3.3 Sensitivity analysis Sensitivity analysis for each technology scenario – Main parameters driving levellized €/km priceFIGURE 7 Common Across Options 2.50383.71€/km (Baseline) 25.6k 6.56 150k 1.08 0.28 0.5718 54.87k 2.56 350k 2.26 0.4 0.69 3.00 4.00 5.00 3.50 4.50 5.50Diesel bus maintenance cost (€/km)Diesel bus fuel consumption (l/km)Diesel fuel price (€/litre)Diesel bus unit price (€)WACC (%)Bus driver salary (€)Bus utilization (%)Diesel bus TCO sensitivity E-bus TCO sensitivity EV bus maintenance cost (€/km)Charging station number of unitYear of investment Electricity price (€/kWh)EV bus unit price (€)EV bus government subsidy (%) WACC (%)Bus driver salary (€/driver)Bus utilization (%) 2.50 3.00 4.00 5.00 3.50 4.50 5.50EV bus battery replacement cost (% of new bus price)38 25.6k 75 6.56 368k 2050 0.0918 54.87k 0 2.56 750k 2050 0.30 25 45 13 50 0.30 0.433.35€/km (Baseline) Decarbonizing Aviation Ground Operations: Alternative Bus Technologies 21

Decarbonizing Aviation Ground Operations 2025