以长江上游某大型水电站为案例,根据国际标准化组织碳足迹量化标准(ISO14067)评价流程,对该水电站全生命周期(建设阶段,运行维护阶段,退役阶段)碳足迹进行估算,并着重考虑了蓄水前后水库温室气体通量差异。研究以碳足迹系数和能源回收率作为指标进行评价,结果表明生命周期碳足迹为5 417.0万t CO2eq,碳足迹系数为7.0-13.1 g CO2eq/kW·h,中位值为9.4 g CO2eq/kW·h,该水电站项目能源回收率达236.4。与各种能源电站以及国内外同类型水电站相比较,该水电站碳足迹明显较低,且能源回收率显著较高,说明以该水电站为代表的我国西南水电具有显著的优质性,大力开发水电能有效节能减排,明确了生命周期评价方法对于水电站碳足迹评估的适用性。
This paper selects a large hydropower station in the upper Yangtze River as a case. Life cycle assessment was used to estimate its greenhouse gas(GHGs) emission according to the standardized processes(ISO14067) for carbon footprint quantization,focusing on the difference before and after the impoundment from three stages, i. e. construction, operation and decommission. Carbon emissions factors kW · hand energy payback ratio are selected as the indicators of cleanliness and quality. The results showed that: the carbon footprint of the hydropower station was 54. 17 million tons CO2eq,carbon emission kW·hfactor of the hydropower station was 7. 0-13. 1 g CO2eq/kW · h,and energy payback ratio was 236. 4. Compared with other kinds of power plants and other hydropower stations with reservoir,the carbon footprint is obviously lower and energy payback ratio is significantly higher. This implies the high quality and cleanliness of hydropower resource in the Southwest China. We came to a conclusion that hydropower development may promote the energy-saving and emission-reduction; life cycle assessment(LCA) is applicable for analysis on carbon footprint of hydropower project.