Grid Flexibility Enhancement through Operational Adjustments in Waste-to-Energy Plants

As renewable energy penetration increases, grid flexibility becomes critical for avoiding output curtailment. This study explores the potential of waste-to-energy (WtE) facilities to provide such flexibility through operational adjustments. Using one-minute interval operational data from two Japanese WtE plants, we developed a mathematical model linking waste input, steam generation, and power output. The analysis shows that dynamic reallocation of waste processing allows for significant power variation―1,757-2,204kWh and 946-1,688kWh per minute―particularly under single-incinerator operation. These findings suggest that existing WtE infrastructure, traditionally designed for stable operation, can act as a controllable resource. Building on facility-level insights, we estimated the national potential using statistical data on plant capacity and operating conditions. The results suggest a nationwide variable generation potential of approximately 4,182GWh annually, with around 934GWh available during typical curtailment hours (8: 00-16: 00). Although based on simplifying assumptions, such as uniform operating behavior and linear scalability, the estimates highlight a significant untapped resource. This suggests that re-evaluating WtE plants as distributed flexible assets could contribute meaningfully to integrating renewable energy without new infrastructure investment.