Research News

Satellite Successfully Monitors Power Plant CO2 Emissions from Space

February 24, 2023

The CO2 emissions from coal-fired power plants are a major source of carbon emissions in China. However, the existing emission inventory does not accurately reflect current emissions because of a lag in the statistical data and the accuracy limit for emissions factor. 
A research team led by Dr. SHI Yusheng from the Aerospace Information Research Institute (AIR) of the Chinese Academy of Sciences (CAS) developed a method for estimating CO2 emissions from coal-fired power plants based on an improved Gaussian plume model and the Orbiting Carbon Observatory 2/3 satellite. 

The study was published in Journal of Cleaner Production on Feb. 22.

The team quantified CO2 emissions from six coal-fired power plants (> 3000 MW) in China using 14 plumes from the OCO-2 (2014.09.06–2021.10.01) and OCO-3 (2019.08.06–2021.10.01) datasets. Four of the plumes are in good agreement with those from co-located the Tropospheric Monitoring Instrument measurements of co-emitted NO2. The estimated CO2 emissions ranged from 31.81–99.71 kt/d with correlation coefficient of 0.47–0.95. The uncertainty of individual plumes varied from 8% to 42% (1σ), with wind speed being the greatest source of uncertainty, and the average XCO2 enhancement of all power plants in this study is less than 1 ppm when the wind speed increases to about 10 m/s. 

After validation, the results show high agreement with the existing emission inventory. However, GUO Wenyue, the first author of this study, found that the Carbon Monitoring for Action may have underestimated the CO2 emissions from Tuoketuo due to the timing of the update, and carbon brief may have underestimated the emissions from Wujiaqu by ignoring the high emission factor of lignite. 

This study fills a gap in the monitoring of carbon emissions from important point sources and helps countries and regions to develop targeted carbon reduction policies. In addition, the estimated specific emission values can serve to validate emission inventories and identify unintentional and clandestine emissions, providing more accurate input data for atmospheric chemistry models.
 
Flowchart of satellite retrieved CO2 emissions from power plants. (Image by AIR)