据阿拉伯贸易网站3月9日消息称，根据国际能源署的最新分析，随着世界经济从疫情中复苏，并严重依赖煤炭为增长提供动力，全球能源相关的二氧化碳(CO2)排放量在2021年上升了6%，至363亿吨，创下历史最高水平。

国际能源署的分析显示，全球二氧化碳排放量增加了20多亿吨，以绝对值计算是历史上最大的，超过了前一年大流行导致的下降。

2021年，恶劣的天气和能源市场条件(尤其是天然气价格的飙升)加剧了能源需求的复苏，尽管可再生能源发电实现了有史以来最大的增长，但这导致了更多的煤炭燃烧。

全球二氧化碳排放量和能源需求数据基于 IEA对各个地区和燃料的详细分析得出的，这些分析依据的是最新的国家官方数据以及公开的能源、经济和天气数据。结合IEA上月发布的甲烷排放估计，以及一氧化二氮和燃除相关的二氧化碳排放估计，新的分析表明，能源领域的总体温室气体排放在2021年上升到有史以来的最高水平。

2021年，煤炭占全球二氧化碳排放总量增长的40%以上，达到153亿吨的历史最高水平。天然气的二氧化碳排放量反弹至75亿吨，远远高于2019年的水平。由于 2021 年全球运输活动（主要是航空业）的复苏有限，石油产生的二氧化碳排放量为 107 亿吨，远低于大流行前的水平。

尽管煤炭使用量出现反弹，但2021年可再生能源和核能在全球发电中所占份额高于煤炭。基于可再生能源的发电量达到了历史新高，2021年超过了8000太瓦时(TWh)，比2020年的水平高出了创纪录的500太瓦时。风能和太阳能光伏发电量分别增加了270太瓦时和170太瓦时，而水力发电由于干旱的影响而下降，尤其是在美国和巴西。

由于天然气价格创纪录高位，2021年煤炭发电的使用量有所增加。在2021年的大部分时间里，美国和许多欧洲电力系统现有燃煤电厂的运营成本大大低于天然气电厂。天然气转煤炭使全球发电的二氧化碳排放量增加了1亿吨以上，尤其是在美国和欧洲，天然气和煤炭发电厂之间的竞争最为激烈。

曹海斌 摘译自 阿拉伯贸易

原文如下：

Global CO2 emissions rebound to all-time high in 2021: IEA

Global energy-related carbon dioxide (CO2) emissions rose by 6% in 2021 to 36.3 billion tonnes, their highest ever level, as the world economy rebounded from the pandemic and relied heavily on coal to power that growth, according to new IEA analysis.

The increase in global CO2 emissions of over 2 billion tonnes was the largest in history in absolute terms, more than offsetting the previous year’s pandemic-induced decline, the IEA analysis shows.

The recovery of energy demand in 2021 was compounded by adverse weather and energy market conditions – notably the spikes in natural gas prices – which led to more coal being burned despite renewable power generation registering its largest ever growth. 

The global CO2 emissions and energy demand numbers are based on the IEA’s detailed region-by-region and fuel-by-fuel analysis, drawing on the latest official national data and publicly available energy, economic and weather data. Combined with the methane emissions estimates that the IEA published last month and estimates of nitrous oxide and flaring-related CO2 emissions, the new analysis shows that overall greenhouse gas emissions from energy rose to their highest ever level in 2021.

Coal accounted for over 40% of the overall growth in global CO2 emissions in 2021, reaching an all-time high of 15.3 billion tonnes. CO2 emissions from natural gas rebounded well above their 2019 levels to 7.5 billion tonnes. At 10.7 billion tonnes, CO2 emissions from oil remained significantly below pre-pandemic levels because of the limited recovery in global transport activity in 2021, mainly in the aviation sector.

Despite the rebound in coal use, renewable energy sources and nuclear power provided a higher share of global electricity generation than coal in 2021. Renewables-based generation reached an all-time high, exceeding 8 000 terawatt-hours (TWh) in 2021, a record 500 TWh above its 2020 level. Output from wind and solar PV increased by 270 TWh and 170 TWh, respectively, while hydro generation declined due to the impacts of drought, notably in the United States and Brazil.

The use of coal for electricity generation in 2021 was intensified by record high natural gas prices. The costs of operating existing coal power plants across the US and many European power systems were considerably lower than those of gas power plants for the majority of 2021. Gas-to-coal switching pushed up global CO2 emissions from electricity generation by well over 100 million tonnes, notably in the US and Europe where competition between gas and coal power plants is tightest.