Sustainable aviation fuels: Evaluating environmental and operational impacts

Abstract

Between 2013 and 2018, commercial aviation saw a 70% increase in carbon dioxide (CO2) emissions, significantly outpacing United Nations projections. This alarming trend is anticipated to continue, with emissions potentially tripling by 2050, driven by economic expansion and an increasing dependence on fossil fuels. In 2022, the aviation industry’s energy consumption reached 12.1 MJ/RTK, with projections forecasting a 2.8 to 3.9-fold increase by 2040. Without a strategic shift towards sustainable alternatives, aviation emissions are expected to reach 2,000 megatons by mid-century, posing a severe threat to global climate stability. This study emphasizes the urgent need for the aviation sector to adopt high-energy, reliable alternative fuels that can mitigate its environmental impact. A comprehensive evaluation and comparison of potential alternative fuels are presented, focusing on their energy densities, production processes, and ecological footprints. The research highlights the potential of these alternatives to meet the industry’s energy demands while significantly reducing greenhouse gas emissions. Technological advancements in fuel production and aircraft propulsion are also explored, underscoring their role in achieving meaningful emissions reductions. The study argues that integrating sustainable practices and fostering innovation within the aviation sector is critical for ensuring long-term sustainability and resilience. By transitioning to alternative fuels and embracing new technologies, the aviation industry can address its environmental challenges and lead the way in global efforts to combat climate change and achieve net-zero emissions by 2050.

Keywords

• Aviation
• CO2 Emission
• Hydrogen
• SAF
• sustainable fuels

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