Beyond greenhouse gases - a natural capital-based sustainability assessment framework for the waste-to-energy approach

Although greenhouse gas (GHG) emissions and marine plastic reduction have been recognised as essential factors for the sustainability performance of waste-to-energy (WTE) facilities, there is a lack of comprehensive evaluation tool for quantifying the environmental, social and economic impacts caused by WTE projects. To fill the gap, this study developed a natural capital-based sustainability assessment (NCSA) framework for evaluating the sustainability of WTE projects. The merits of the NCSA framework include (1) the quantification of the benefits caused by the avoidance of marine plastic pollution by WTE projects, and (2) an inclusive sustainability evaluation framework that holistically assesses the environmental, social and economic performance associated with GHG and marine plastic reduction. The NCSA framework has been demonstrated in the case study on the Sanya WTE Project. The results showed that the Sanya WTE Project emitted 265,376 tonnes of CO2e of GHG and prevented 28,242 - 75,312 tonnes of marine plastic during the study period, which is equivalent to a net benefit of CNY41.90 million - 464.45 million. The case study demonstrated that the NCSA framework is a comprehensive evaluation tool that provides clear and sound results for guiding decisions towards sustainable waste management and the overall sustainability of cities.