Techno-economic analysis, emergy assessment, and optimization using response surface methodology of a solar and biomass-based co-generation system

Integrating renewable energy sources into systems is crucial for sustainability and reducing CO₂ emissions. The sorption-enhanced gasification process, when combined with renewables, offers a path toward sustainable energy systems. In this study, a novel integration of a solar-based sorption-enhanced gasification process for biomass is proposed, aiming for electricity and hydrogen generation. The entire system's performance has been investigated from the perspectives of energy, exergy, economics, and emergy analysis.

Furthermore, response surface methodology is employed to optimize the overall system performance in terms of energy and exergy efficiencies and the levelized cost of energy. The study's results reveal that the integrated system shows its optimum operational condition at a steam-to-biomass ratio of 0.53 and a CO₂ capture efficiency of 65 %. The optimum energy efficiency of the overall system is determined to be 67.2 % with a net electrical power generation of 5.251 MW. The optimum exergy efficiency for the whole system is determined at 71.89 %. Optimization results report a levelized cost of energy of 7.87 $/MWh. From a sustainability analysis perspective, emergy analysis results indicate that the introduced system, with a renewability index of 0.22, has a low dependency on non-renewable inputs. With a sustainability index of 1.95, the system qualifies as moderately sustainable, demonstrating superior performance compared to conventional co-generation systems.