Quantifying On-Road Black Carbon Emission Factors in Türkiye: Historical Assessment and Mid-Century Scenario

This study evaluates Well-to-Wheels (WTW) black carbon (BC) emission factors across road-transport vehicle technologies in Türkiye. Historical WTW BC emission factors for the 2013–2023 period were assessed to characterize changes across vehicle and powertrain technologies, while hypothetical 2040 and 2050 scenarios were examined under alternative vehicle-technology and electricity-generation pathways. The analysis considers conventional and alternative powertrains, including internal combustion engine vehicles, hybrid vehicles, battery electric vehicles, and fuel cell vehicles, together with changes in vehicle technology and electricity-generation pathways. The results indicate a decline in the calculated WTW BC emission factors for the evaluated vehicle technologies over the historical assessment period, with changes associated with the time-dependent vehicle and fuel parameters incorporated into the model. The 2040 and 2050 results further show that WTW BC emission factors for electrified and hydrogen-based powertrains vary substantially depending on the upstream electricity-generation pathway. In particular, low-BC electricity pathways result in substantially lower WTW BC emission factors within the defined system boundary. These findings provide a comparative assessment of WTW BC emission factors across vehicle and energy pathways and contribute to the evaluation of BC mitigation options in Türkiye’s road-transport sector.