Retro-techno-economic-environmental analysis improves the operation efficiency of 1G-2G bioethanol and bioelectricity facilities

In order to assess the feasibility of new, environmentally friendly technologies for energy generation in a neutral carbon economy, economic and environmental metrics must be simultaneously assessed. Retro-Techno-Economic-Environmental Analysis (RTEEA) is a computational method that identifies ranges of feasible operation for industrial processes, condensing complex information into graphic plots that are easily interpreted by users. RTEEA was applied to define windows of feasible operations for a biorefinery that produces first- and second-generation ethanol plus bioelectricity from sugarcane. The net present value of the business and environmental metrics, using the CML-IA impact assessment method, were combined. Influential process variables were identified with global sensitivity analysis. The metrics were clustered into three groups, and RTEEA diagrams showed the range of feasible operations for each metric, after an uncertainty analysis. It was observed that if economic feasibility is achieved, all environmental impacts of second-generation ethanol will be lower than the first-generation ethanol, except for the photochemical oxidation index.