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In general, the certified pathways for the production of sustainable aviation fuels (SAFs) are still far from being competitive with fossil kerosene, although they have the potential to reduce greenhouse gas (GHG) emissions. However, the mitigation costs related to SAFs and how they compete with the carbon credits market remain unclear. The present study addressed these issues, evaluating SAF pathways based on hydrotreatment (HEFA process) of soybean oil, palm oil, used cooking oil (UCO) and beef tallow; dehydration and oligomerization of ethanol (ATJ technology) obtained from sugarcane, lignocellulosic residues, and steel off‐gases; and the thermochemical conversion of lignocellulosic residues using the Fischer–Tropsch (FT) process and hydrothermal liquefaction (HTL). Residue‐based pathways had lower mitigation costs. Used cooking oil / HEFA had the lowest value (185 USD tCO2e−1), followed by the thermochemical conversion of forestry residues (234–263 USD tCO2e−1). Of the 1G pathways, SAF production from 1G sugarcane ethanol (SC‐1G/ATJ) performed better (495 USD tCO2e−1) than oil‐based ones. In comparison with the carbon market, the mitigation costs of SAFs are much higher than the current prices or even future ones. However, several concerns about the credibility of the emission units and their effective mitigation effects indicate that SAFs could play an important role in aviation sector goals. Considering the potential of supplying SAF and mitigating emissions, SC‐1G/ATJ was suggested as a preferred alternative in the short term. Of the residue‐based pathways, tallow / HEFA and FT of forestry residues are suggested as strategic alternatives. © 2020 The Authors. Biofuels, Bioproducts, and Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd

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The biodiesel blending mandate was launched at 2005 in Brazil, by a governmental program based mainly on sustainability concerns, especially toward social and environmental aspects. Since 2007, B7, i.e., 7% biodiesel in diesel, in volume terms, has been mandatory, and B10 is the next target. In this context, this paper aims to evaluate the biodiesel program along the ten years from 2005 to 2015 in Brazil, considering the evolution of the estimated costs and the auction prices intending to verify some tendency in a learning curve perspective. A decreasing tendency of the biodiesel production costs and prices was observed, with a reduction of the profit margin in recent years, suggesting a learning trend. The Progress Ratio (PR) of the whole period was 101.7%, but in the 2011–2015, it was estimated at 59.3%. Relevant technology changes in biodiesel production process were not verified, but the increased competitiveness in the market, the gains of scale of plant profiles, and mainly the decrease of soybean oil prices explain this evolution. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd