Carbon capture and storage chains in Brazil: A multi-criteria assessment of the ethanol sector

Achieving negative emissions through bioenergy with carbon capture and storage is crucial for a net-zero future. In Brazil, this technology has strong potential in the ethanol sector, but cost-efficient deployment requires a multi-criteria assessment of CO2 transport and storage, considering geophysical, economic, social, and political factors. This paper assesses optimal onshore regions for such systems deployment employing a hybrid framework based on geographic information systems and multi-criteria decision-making method, assessing five scenarios. The Central and Northern regions of São Paulo state emerged as the most suitable for capturing and storing CO2 from ethanol fermentation, enabling up to 40% emissions reduction per year, with a cumulative storage of 290 MtCO2 by 2050. Transport and storage costs range from 22.86 to 56.06 US$2018/tCO2. Notably, minimizing source-sink distance is not always advantageous. Under current carbon credit prices, some projects could already be viable if shared costs among stakeholders are kept low, while others require subsidies or tax credits for becoming feasible. Nevertheless, expanding data on saline formations is key to unlocking national carbon capture and storage chains.