Baseline options and greenhouse gas emission reduction of clean development mechanism project in urban solid waste management

The Clean Development Mechanism (CDM) was adopted in the Kyoto Protocol as a flexibility mechanism to reduce greenhouse gases (GHGs) and has been started with such projects as improving efficiency of individual technology. Although applying various countermeasures to urban areas has significant potentials for reducing GHGs, these countermeasures have not been proposed as CDM projects in the practical stage. A CDM project needs to be validated that it will reduce GHGs additionally compared with a baseline, that is, a predictive value of GHG emissions in the absence of the project. This study examined the introduction of solid waste incineration with electricity generation into three different cities, A, B and C. The combination of main solid waste treatment and fuel source are landfill and coal, respectively, in City A, incineration and natural gas in City B, and landfill and hydro in City C. GHG emission reductions of each city under several baseline options assumed here were evaluated. Even if the same technology is introduced, the emission reduction greatly varies according to the current condition and the future plan of the city: 1043–1406 kg CO₂/t of waste in City A, 198–580 kg CO₂/t in City B, and wide range of zero to over 1000 kg CO₂/tin City C. Baseline options also cause significant difference in the emission reduction even in the same city (City C). Incinerating solid waste after removing plastics by source separation in City B increased GHG emission reduction potential up to 730–900 kg CO₂/t, which enhances the effectiveness as a CDM project. This revised version was published online in August 2006 with corrections to the Cover Date.