Thermodynamic analysis of sugarcane-corn integration for flex ethanol and bioenergy production

Addressing the volatility of global oil markets and the increasing demand for sustainable bioenergy systems, this study conducts a comprehensive thermodynamic assessment of a flex biorefinery integrating sugarcane and corn for continuous ethanol and power production. Three operational scenarios are evaluated: (i) a conventional sugarcane-only plant operating during the harvest season; (ii) a sequential configuration producing corn ethanol during the off-season using stored bagasse; and (iii) a fully integrated, year-round operation with simultaneous sugarcane and corn processing. Mass, energy, and exergy balances are applied to quantify steam distribution, cogeneration performance, and overall system efficiency under each scenario. The results demonstrate that operational integration significantly enhances resource utilization and reduces idle capacity. Compared to the baseline configuration, the fully integrated scenario increases the overall annual energy efficiency from 25.3% to 61.3% and raises ethanol production from approximately 162,000 m³/year to 862,000 m³/year. Moreover, the Energy Economy due to Cogeneration (EEC) improves from negative values to a positive index (EEC = 0.16), indicating a transition from energy self-consumption to net energy surplus. These results provide quantitative evidence that flex biorefineries with simultaneous sugarcane–corn operation offer substantial thermodynamic advantages, including higher efficiency, improved cogeneration performance, and enhanced production continuity. The proposed framework supports the strategic development of flexible bioenergy systems for the Brazilian sugar-energy sector and other biomass-based industries.