Abstract: In the face of environmental and energy challenges, the search for cleaner and sustainable energy sources has become a global priority. In this scenario, biodiesel is an important biofuel for diversifying the Brazilian energy matrix and mitigating greenhouse gas emissions. Biodiesel is commercially produced through the transesterification process of vegetable oils or animal fats with a short-chain alcohol in the presence of a catalyst. Various oilseeds can be used for biodiesel production, with soybeans being the most commonly used in the national context, using methanol as the alcohol and sodium hydroxide as the catalyst. RenovaBio is Brazil’s National Biofuels Policy established in 2017. Its main objective is to rejuvenate the bioenergy industry in Brazil and reduce greenhouse gas emissions. It aims to stimulate a more sustainable biofuel production based on performance assessments of production units, reflecting individual performance in mitigating emissions compared to fossil fuels for carbon credit issuance. Since different feedstocks generate different environmental burdens in biodiesel production, evaluating various production alternatives is essential within the perspectives of new public policies incentivizing the production of biofuels with a lower carbon footprint. In this context, the objective of this study was to analyze the environmental impact resulting from biodiesel production using different feedstocks in the Brazilian scenario through a Life Cycle Assessment (LCA) methodology. The SimaPro software was used for LCA analyses, utilizing the Ecoinvent 3 database. For the assessment of the potential impact of climate change, the IPCC 2021 method with a 100-year methodology was employed. The following raw materials were compared: Brazilian soybean mix, cotton, and animal fat, with the analysis indicating the best environmental performance for animal fat biodiesel. A comparison was made between soybean biodiesel produced in four different states in Brazil – Goiás, Paraná, Rio Grande do Sul, and Mato Grosso. Small variations in emissions were observed based on the production of each state, with a higher contribution from the agricultural phase of soybean production in the emissions impact during the biodiesel production chain. Finally, an analysis was conducted on the substitution of methanol with ethanol during production, revealing an increase in greenhouse gas emissions related to the agricultural phase of sugarcane production. Even in the worst-case scenarios studied, when compared to petroleum diesel, biodiesel is the best alternative fuel for use in diesel cycle engines to reduce greenhouse gas emissions.

Keywords: Biodiesel, LCA, Soybean, Global Warming Potential