Invited Session: Climate Change

Quantifying GHG Emissions Reduction from Waste and Resource Management Techniques

Tuesday, September 26, 2017
8:00 – 8:30
Convention Center

Life-cycle analysis (LCA) models evaluate the full benefits of waste management decisions and provide the perspective needed to guide long-term planning decisions for achieving environmental sustainability. LCA’s main limitations arise from the spatial and temporal scale of analysis, which make it less precise in defining time-dependent landfill methane emissions that dominate waste sector GHG emissions in many countries. This paper explores the effectiveness of LCA for guiding local solid waste management decisions in developing countries in light of uncertainties caused by the temporal and spatial scales of LCA and by its assumptions of linearity and heavy reliance on good waste composition data. To evaluate GHG emissions in developing countries where landfill methane dominates, and to monitor progress in emissions reduction from benchmark levels, city planners need models that provide realistic estimates of annual landfill methane emissions by accounting for ever-changing conditions at specific disposal sites. LCA’s scale of analysis is appropriate for setting goals, but compounds the large uncertainties in landfill emissions estimates, and is unable to evaluate the achievements of interim steps towards reaching sustainability that developing countries will need to undergo, including the closing and remediation of existing dump sites, and the collection and destruction of landfill methane.

Following this presentation, participants will be able understand the limitations of LCA, including the effects of the temporal and spatial scales of analysis, on its effectiveness for guiding local solid waste management decisions in developing countries.


Alex Stege, Senior Project Advisor, SCS Engineers, Arizona

Alex Stege

Alex Stege is a senior project advisor for SCS Engineers with over 30 years of experience in environmental research and consulting, including twenty-seven years at SCS Engineers. For the past 20 years, Mr. Stege has supported U.S EPA, the World Bank, landfill owners, and LFG project developers in evaluating landfill gas recovery potential and LFG utilization project feasibility at hundreds of sites throughout the world. Mr. Stege leads SCS’s LFG modeling practice, which is based on the scientific application of actual flow and site data to develop an empirically calibrated LFG recovery model. Mr. Stege has given presentations on modeling landfill methane generation and recovery at conferences hosted by the following organizations: ISWA, SWANA, LMOP, the Global Methane Initiative (GMI) Partnership, the Environmental Research and Education Foundation (EREF), and the Global Waste Management Symposium. Mr. Stege was the author of LMOP/GMI LFG models for Central and Eastern Europe (2014), Colombia (2010), Ukraine (2009), Mexico (Version 1 [2003] and Version 2 [2009]), and Central America (2007). Mr. Stege also is a primary author of the Solid Waste Emissions Estimation Tool (“SWEET”), which is currently being developed by SCS Engineers and Abt Associates for the Climate and Clean Air Coalition.