【摘要】 电力碳足迹旨在测度发电过程中所引起的生命周期CO2排放水平。本研究从地球碳循环的角度入手,在综合大量研究数据的基础上,针对不同电力来源的碳排放特征,结合地表覆被的碳吸收能力,分类测算了全球平均电力碳足迹当量(即单位电力消费量所产生的生命周期碳足迹),并实证分析了2000—2008年全球电力碳足迹的构成及变化。结果表明:煤炭类火电(以下简称煤电)、石油类火电、天然气类火电、水电和核电的全球平均碳足迹当量分别为131.3×10-6、95.8×10-6、56.6×10-6、38.8×10-6、1.9×10-6hm2·(kW·h)-1,火电特别是煤电的环境影响显著大于水电和核电;2000—2008年,全球电力碳足迹由730.7×106hm2增至1101.8×106hm2,其中火电占比由60.0%增至68.1%,煤炭取代石油成为火电碳足迹的主要构成部分,而水电和核电占比则分别降至30.7%、1.3%;全球电力结构总体趋于劣化,平均碳排放系数由265.8×10-3kg·(kW·h)-1增至315.4×10-3kg·(kW·h)-1,火电特别是煤电在很大程度上决定着电力碳排放的强度与规模。更多还原

【Abstract】 Carbon footprint of electricity is a measurement of the amount of life cycle CO2 emission associated with the whole process of power generation. From the perspective of global carbon cycle, the characteristics of carbon emission from different power generations are partially the land cover’s carbon sequestration capacity. This paper calculated the average carbon footprint equivalent of global electricity, i.e., the life cycle carbon footprint for per unit of electricity consumed, and analyzed the composition of carbon footprint of global electricity and its changes in 2000-2008, based on the synthesis of large amount of investigation data. The world-average global carbon footprint equivalents of coal, oil, and natural gas used for thermal electricity generation, and of hydro-electricity and nuclear electricity were 131.3×10-6, 95.8×10-6, 56.6×10-6, 38.8×10-6, 1.9×10-6 hm2·(kW·h)-1, respectively, indicating that the environmental impact of thermal electricity, especially coal-based electricity, was significantly greater than that of hydro-electricity and nuclear electricity. From 2000 to 2008, the carbon footprint of global electricity increased from 730.7×106 hm2 to 1101.8×106 hm2, in which, the proportion of thermal electricity increased from 60.0% to 68.1%, in particular coal replaced oil to be the largest source of the carbon footprint of thermal electricity, while the proportion of hydro-electricity and nuclear electricity fell to 30.7% and 1.3%, respectively. Overall, the structure of global electricity revealed a trend towards deterioration, for the world-average carbon emission coefficient of electricity increased from 265.8×10-3 kg·(kW·h)-1 in 2000 to 315.4×10-3 kg·(kW·h)-1 in 2008. The results highlight the need for reducing the use of thermal electricity, especially coal-based electricity, which largely determines the intensity and scale of carbon emission from power generation.更多还原