A Thermo-Economic and Exergy-Based Analysis of Sustainable Aviation Fuel Production in Brazil: Policy, Efficiency, and Decarbonization Pathways

The global aviation sector faces mounting pressure to decarbonize, with sustainable aviation fuels (SAFs) representing a critical transitional solution. Brazil, endowed with abundant biomass resources and a mature biofuel industry, holds significant potential for SAF production. However, the economic viability, energy efficiency, and environmental impact of SAF pathways remain underexplored through integrative energy economics frameworks. This study applies principles of thermo-economics and exergy economics to evaluate the technical, economic, and policy dimensions of SAF production in Brazil. By examining the exergetic efficiency and life-cycle costs of key production routes, such as HEFA, ATJ, Fischer–Tropsch, and SIP, we aim to identify optimal pathways for scaling SAF within Brazil’s energy and climate policy landscape.

The methodology integrates a systematic review of Brazilian SAF initiatives, regulatory frameworks, and production technologies with thermo-economic and exergy analyses. Data were drawn from government publications, technical reports, academic literature, and industry roadmaps (2010–2025). Exergy analysis was applied to quantify the useful energy potential and irreversibilities of each SAF conversion pathway. Thermo-economic models were developed to assess the cost of exergy destruction and the trade-offs between capital investment, operating costs, and thermodynamic performance. Policy instruments such as RenovaBio, the Fuel of the Future Program, and tax incentives were evaluated for their impact on the exergy–economic competitiveness of SAFs relative to conventional aviation kerosene.

The analysis reveals that while Brazil possesses sufficient feedstock potential (particularly from sugarcane residues, wood waste, and used cooking oil), the exergy efficiency of SAF production varies significantly across technologies. Fischer–Tropsch and ATJ routes showed higher exergetic performance for lignocellulosic feedstocks, whereas HEFA exhibited lower exergy losses but faced feedstock limitations and higher hydrogen demand. Thermo-economic assessment indicated that SAF production costs remain 20–80% above fossil kerosene, largely due to exergy inefficiencies in conversion and upgrading stages. The study also highlights regulatory gaps, including the absence of a SAF-specific mandate, complex environmental licensing, and post-blending taxation issues, which collectively hinder investment and scale-up. The integration of exergy-based metrics into policy design could prioritize high-efficiency pathways and align incentives with decarbonization goals.

To accelerate SAF deployment, Brazil must adopt an integrated energy policy approach that combines thermo-economic optimization with supportive regulation. The principal recommendations include (1) introducing exergy-based subsidies to reward high-efficiency SAF pathways; (2) simplifying environmental licensing through multi-level governance coordination; (3) establishing an SAF blending mandate linked to carbon intensity reduction; and (4) fostering public–private partnerships for R&D in exergy-efficient conversion technologies. This study demonstrates that thermo-economic and exergy analyses provide a robust framework for guiding SAF policy, enabling Brazil to leverage its bioenergy potential while advancing toward its climate commitments under the Paris Agreement.