## 1 Introduction  
Over the past several decades, global conversations and strategies have increasingly focused on sustainability and environmental conservation [1]. This heightened interest has been driven by mounting scientific evidence revealing the detrimental impacts of human activities on Earth's ecosystems, climate, and biodiversity [2]. A significant portion of these adversities can be attributed to the relentless emission of greenhouse gases (GHGs) into the atmosphere [3]. At the core of the climate challenge is the combustion of fossil fuels, which is deeply embedded in modern economies across sectors such as transportation, energy generation, and industrial activities [4, 5, 6]. Fossil fuel combustion releases substantial amounts of carbon dioxide (CO\({}_{2}\)), methane (CH\({}_{4}\)), and other GHGs [7, 8]. Achieving emissions reduction goals is inherently tied to reducing CO\({}_{2}\) emissions [9]. These gases trap heat in the Earth's atmosphere, leading to global warming and driving the cascade of changes known as climate change [10]. Aviation accounts for almost 3% of global CO\({}_{2}\) emissions, and aviation's emissions are rising as other industries' emissions decline [11]. Figure 1 illustrates global carbon dioxide emissions from aviation. Highlighting the magnitude of this challenge, the International Energy Agency (IEA) has presented alarming data: the energy sector alone is responsible for nearly three-quarters of global GHG emissions [12, 13]. This paints a concerning picture, considering the vast array of other sectors and their cumulative contribution to this global challenge [14, 15]. A particularly pressing concern is the rapid expansion of the global transportation sector [16, 17]. Forecasts suggest that by 2050, the number of vehicles on the planet will have doubled [18, 19]. This escalation not only is indicative of an increased demand for mobility solutions but also represents an enormous surge in energy consumption and associated carbon emissions [20; 21]. With current technologies and fuels, this growth will likely lead to an unsustainable increase in GHG emissions, exacerbating the already severe impacts of climate change [22; 23]. Amidst this challenging backdrop, the emergence of e-fuels offers a glimmer of hope [24; 25]. Sustainable aviation fuel (SAF) emerges as a more accessible intermediate-term solution for reducing the aviation industry's carbon footprint compared to other renewable energy such as hydrogen and batteries [26]. This accessibility is primarily driven by SAF's compatibility with existing aircraft engines and fuel infrastructure, allowing for a seamless transition without the need for extensive modifications. Unlike hydrogen, which requires significant advancements in storage and handling technology due to its low energy density and cryogenic requirements, SAF can be integrated into current fuelling systems with minimal changes. Batteries, on the other hand, face limitations in energy density and weight, making them less viable for long-haul flights where significant power and endurance are essential. Figure 2 compares the technological potential of renewable aviation fuels. MPP's Aviation Transition Strategy outlines a shared vision for a low-carbon future in the industry, with milestones for both 2050 and the near term. For instance, it specifies that 10-15% of jet fuel demand must be met with SAFs by 2030 to initiate the transition to net-zero emissions in the 2030s and 2040s [27]. SAF, derived from renewable sources such as biomass, waste oils, and synthetic processes, offers a practical and scalable approach to decarbonising aviation. It leverages existing supply chains and technologies while providing a substantial reduction in greenhouse gas emissions, thus serving as a critical bridge towards more sustainable aviation in the near future. Figure 1: The global CO\({}_{2}\) emissions of the aviation industry since the beginning of the aviation industry [11].