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6C - LCA and Economics: Input/Output Analysis (TU2/2) Hybrid Life-cycle Assessment of Electricity Generation. Horvath, Arpad1, Pacca, Sergio1, 1 University of California, Berkeley, Berkeley, CA, USA ABSTRACT- With ever-increasing demand for electricity worldwide, it is essential to perform life-cycle assessments (LCA) of various electricity generation technologies. Studies conducted in the U.S. have not yet assessed the environmental effects of building and maintaining the power plants, but have focused largely on smokestack emissions. A hybrid LCA study of electricity generation technologies from renewable (photovoltaics, wind, and hydropower) and non-renewable (coal and natural gas) sources is discussed. A combination of process-based (SETAC-ISO) and economic input-output analysis-based LCA (EIO-LCA) is employed. The hybrid LCA method allows for an integration that may enhance the advantages and eliminate the disadvantages from the analysis. We quantify greenhouse gas emissions and the corresponding global warming effect (GWE) from construction and maintenance, fuel burning, flooded biomass decay in the hydropower plant′s reservoir, and loss of net ecosystem production (NEP). The economic costs of the various options are integrated with the environmental results. All power plants reflect U.S. conditions, and have been scaled and co-located so that a comparison becomes appropriate. The time frame of the analysis was constrained to 40 years due to recognition of uncertain technological advances in energy systems over extended planning horizons. We discuss sensitivity analysis of the technologies due to periodic upgrades and ecosystem variations for technologies where NEP is important: hydropower plants (reservoirs) and location of photovoltaic systems. Of the five electricity generation options, a wind farm and a hydropower plant in an arid zone have the lowest GWE. However, varying the ecosystem type in the hydropower plant′s flooded reservoir may change the ranking dramatically. The results indicate that a hydropower plant′s periodic upgrade is an environmentally and economically beneficial alternative that increases capacity at a negligible GWE. Key words: input-output analysis, Life-Cycle Assessment, electricity, emissions |
