Open Access

Francisco Cancino

• Brazil, the largest sugarcane producer and the second-largest bioethanol producer worldwide relies on this product to spearhead its energy transition, strengthen energy security, mitigate the environmental impact of fossil fuels, and drive economic development. Two complementary energy programs—the Brazilian Alcohol Protocol (Proálcool) and the RenovaBio program—drive the expansion of sugarcane-based ethanol production. These programs aim to reduce Brazil’s dependency on imported oil and integrate biofuels into the energy matrix by promoting ethanol as a renewable fuel alternative. Despite the benefits, the expansion of sugarcane-based ethanol production poses significant environmental challenges. Effective water management is critical, as the industry heavily relies on water for both crop cultivation and processing. Sugarcane farming is water-intensive, requiring large amounts of water for irrigation, which can stress local water resources. Additionally, vinasse, a nutrient-rich by-product of ethanol production, can be beneficially used for fertigation. However, improper management can lead to nutrient runoff, water pollution, and eutrophication of water bodies. Proper strategies for vinasse disposal and utilization include controlled application and treatment before disposal to mitigate its environmental impact. Addressing these environmental challenges requires a holistic approach that includes implementing sustainable agricultural practices, advancing technological innovations, and enforcing regulatory measures. By adopting efficient water use and water circular principles, the sugarcane agroindustry can mitigate its environmental impact and contribute to a more sustainable energy transition and economic development. This research uses field studies and data analysis to assess water use efficiency and vinasse management practices at a sugar and bioethanol plant in Campos dos Goytacazes, Brazil. As the results indicate, the implementation of integrated vinasse management systems could lead to water recovery, estimated to range from 257,405 m3 to 727,490 m3 per year with a unit cost between 0.66 and 3.33 US$ per m3, depending on the system installed. The implementation of these solutions is CAPEX intensive, requiring an initial investment of at least US$ 2.2 million to US$ 8.8 million, corresponding to more than 50% of the total cost of the projects evaluated. Using recycled water in industrial processes and transferring current water withdrawal permits from industrial to agricultural use could increase sugarcane crop yields by up to 79%. This would lead to substantial additional annual revenues to fund the solution. In the best-case scenario, the income-to-cost ratio varies between 6.87 and 25.45, indicating a potential new income from higher ethanol production of up to US$14.7 million per year. The total additional revenue from the implementation of new vinasse management solutions would be beneficial to local agribusiness in water-scarce areas. Improvements in water management practices in ethanol production would make agribusiness more resource-efficient and reduce its environmental impact. This includes reducing the impact caused by vinasse fertigation and decreasing the water footprint of bioethanol production from sugarcane, potentially by up to 34%. Importantly, these water efficiency gains can be achieved without increasing COAGRO's current water withdrawal rates, demonstrating the viability of sustainable water management solutions within the existing operational framework. Furthermore, the research shows that treating vinasse in water-scarce areas can have a positive economic impact, emphasizing the advantages of sustainable water resource management. However, further research into water losses, environmental impacts, and additional infrastructure costs. Assessing how reusing water affects product quality and energy demand is also important. There is potential to improve industrial processes' efficiency and evaluate the impact of enhancements in irrigation and water transport systems.