Environmental Impacts of Direct Combustion Waste-to-Energy as a Two-Pronged Solution for Waste Management and Power Generation in the Philippines

Potential impacts [<i>viz</i>. global warming potential (GWP), ecotoxicity (i.e., marine (METP) and terrestrial (TETP) ecotoxicity potentials), and human health (i.e., human toxicity (HTP), particulate matter formation (PMFP), and particulate ozone formation (POFP) potentials)] of the direct combustion (DC) waste-to-energy (WtE) technology have been evaluated, being prospected as a two-pronged solution for managing waste while potentially contributing to the Philippines’ renewable energy portfolio. Compared to other disposal methods [functional unit (FU) = 1kg MSW)], DC WtE has the least impact in terms of GWP and HTP, has comparable PMFP, POFP, and TETP with sanitary landfill, but has highest METP. Compared to other energy sources [FU = 1kWh], DC WtE can be benign in terms of PMFP, POFP, and GWP versus coal which has the highest impact. Lastly, DC WtE impacts were compared to the stacked overall impacts of coal and sanitary landfill (i.e., status quo; FU = 1kg MSW). Comparison shows that DC WtE has lesser impacts in terms of GWP and human health but has higher impacts in terms of ecotoxicity which necessitates the need of effective waste feed handling, air pollution and wastewater control process, based on current DC WtE model.