Abstract for: Uptake of Sustainable Aviation Fuels: Comparing Mandates, and Industry Targets Using a System Dynamics Air Transport Model

The aviation industry is under increasing pressure to transition toward Sustainable Aviation Fuels (SAFs) to meet decarbonization targets. However, SAF adoption varies significantly due to regional policy frameworks, economic constraints, and industry mandates. In this study we simulate different scenarios for global SAF uptake across different policy environments, assessing the potential availability and market penetration of SAFs by 2030 and 2035. The study utilizes the system dynamics Air Transport System (ATS) model, to evaluate SAF adoption under diverse policy scenarios. The model represents key interactions between airlines, aircraft manufacturers, fuel producers, air travel demand, regulatory mandates and industry targets integrated together with differential equations, allowing a comparative assessment across global regions Model simulations showcase that global SAF adoption will range between 1.8% and 2.7% of total jet fuel consumption by 2030, increasing to 5.7%–7.7% by 2035. The EU and North America are projected to lead SAF adoption due to strong policy incentives and production capacity. The IATA projection of 15%–17% SAF share by 2035 appears highly optimistic, as it does not fully account for production delays and policy uncertainties. The results highlight key bottlenecks in SAF adoption: limited production capacity, unattractive pricing, and HEFA feedstock constraints. Production expansion may take longer than anticipated, delaying supply growth. High costs deter both airlines and producers, requiring stronger incentives. HEFA alone cannot scale; alternative pathways like PtL and AtJ are needed. Without policy support, investment, and technological breakthroughs, SAF adoption may fall short, increasing reliance on carbon offsets instead of real emission reductions. Mostly in the context of writting and solving modelling bugs