Life Cycle Assessment of a Co-Firing Power Generation System in China

Coal and biomass co-firing for power generation can effectively reduce the emissions of CO2 and SO2, which is an economically feasible technology in near term. In this paper, the life cycle assessment (LCA) method was applied on a coal and biomass co-firing project (5% biomass, on an energy basis) and an inventory analysis was conducted on fuel acquisition, fuel transportation, and power plant operation. The fuel consumption and the environmental impacts were calculated for these phases, respectively. Results showed that the total energy input for 10,000 kWh electric power generated by the co-firing system was 108,188.29 MJ. Coal is the major part of all the resources consumed. The greenhouse gas emissions for 10,000 kWh power include CO2 9,190.22 kg, smoke/soot 751.53 kg, SO2 32.61 kg, NOx 32.14 kg, and CH4 30.85 kg. Compared to coal-burning power generation, the co-firing system can reduce the emission of CO2 by 0.0810 kg per kWh or 8.10%. The total environmental impact load was 29.02 standard per capita equivalent (PE) and the main impact on environment was from the emission of dust. If the dust can be appropriately managed, the environmental impact load can also be effectively reduced.