Unleashing the Power in Waste: Comparison of Greenhouse Gas and Other Performance Indicators for Waste-to-Energy Concepts and Landfilling

A CO₂-evaluation is made for landfill and Waste-to-Energy (WtE) concepts. Different concepts are identified and compared for their performance on energy and materials recovery. Performance indicators for WtE are compared; like energy efficiency, EXergy efficiency, the R1-D10 formula from the EU Waste Framework directive, and CO₂-emission and avoidance. It is shown that, due to the biomass content and the avoidance effect due to the recovery of energy and materials, conventional WtE has a near zero CO₂-emission per ton of waste. Optimised WtE can have a significant negative overall emission of 200–300 kgCO₂/ton of waste. This means an absolute net avoidance of CO₂ by WtE. The reduction relative to land filling is as much as 500–1200 kgCO₂/ton of waste. The potential for optimisation of the energy recovery as well as the material recovery of the WtE infrastructure is demonstrated. If WtE is evaluated as a power plant, an optimised plant can have an emission of only 0,336 kgCO₂/kWh, lower than a gas fired electrical power plant, and this absolute figure does not include the avoided landfill emissions. With CHP this can be reduced even further. The actual potential of electricity production from WtE for the EU-15 is calculated to be over 7,5% of total electricity production. Additionally heat and the metal recoveries could be doubled.