A Review on Green Propulsion Technologies using Aerospace Biofuels

Abstract

The integration of biofuels in aviation propulsion systems is a promising solution to mitigate the environmental impact of air travel, particularly by reducing greenhouse gas emissions and reliance on fossil fuels. This review explores the potential of second- and third-generation biofuels, derived from algae, agricultural waste, and municipal waste, which are highly sustainable and offer emissions reductions of up to 50% compared to conventional jet fuel. The production costs, however, remain a challenge, with advanced biofuels such as HEFA-SPK costing 2-3 times more than traditional jet fuels. The adoption of hybrid propulsion systems combining biofuels with electric and hydrogen technologies is emerging as a pathway to further improve fuel efficiency by up to 20% and reduce emissions by 50% or more.Technological advancements in fuel conversion processes and the development of new feedstocks are essential for scaling biofuel production to meet the growing demand for aviation fuels. Furthermore, the integration of biofuels with hydrogen can potentially reduce the carbon footprint of aviation, achieving a 50%+ reduction in GHG emissions and enhancing overall aircraft performance. Policy frameworks, including subsidies, regulatory support, and fuel certification standards, are critical to fostering the development of sustainable aviation fuels (SAFs). The future of aviation lies in the continued innovation of biofuel production technologies, the integration of hybrid propulsion systems, and the collaboration between industry and government to ensure a low-carbon aviation future.