EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Quantifying CO2 emissions of power plants with the CO2M mission

Gerrit Kuhlmann1, Stephan Henne1, Yasjka Meijer2, Lukas Emmenegger1, and Dominik Brunner1
Gerrit Kuhlmann et al.
  • 1Empa, Air Pollution / Environmental Technology, Dübendorf, Switzerland (
  • 2European Space Agency (ESA), ESTEC, Noordwijk, The Netherlands

In this study, we analyse the capability of the Copernicus CO2 monitoring (CO2M) satellite mission to quantify the CO2 emissions of individual power plants, which is one of the prime goals of the mission. The study relies on synthetic CO2 and NO2 satellite observations over parts of the Czech Republic, Germany and Poland and quantifies the CO2 and NOx emissions of the 15 largest power plants in that region using a data-driven mass-balance approach.

The synthetic observations were generated for six CO2M satellites based on high-resolution simulations of the atmospheric transport model COSMO-GHG. To identify the emission plumes, we developed a plume detection algorithm that identifies the location, orientation and extent of multiple plumes from CO2M's NO2 observations. Afterwards, a mass-balance approach was applied to individual plumes to estimate CO2 and NOx emissions by fitting Gaussian curves to the across-plume signals. Annual emissions were obtained by interpolating the temporally sparse individual estimates applying a low-order spline fit.

Individual CO2 emissions were estimated with an accuracy <65% for a source strength >10 Mt CO2 yr-1, while NOx emissions >10 kt NO2 yr-1 were estimated with <56% accuracy. NO2 observations were essential for detecting the plume and constraining the shape of the Gaussian curve. With three CO2M satellites, annual CO2 emissions were estimated with an uncertainty <30% for source strengths larger than 10 Mt yr-1, which includes an estimate of the uncertainty in the temporal variability of emissions. Annual NOx emissions were estimated with an uncertainty <21%. Since NOx emissions can be determined with better accuracy, estimating CO2 emissions directly from the NOx emissions by applying a representative CO2:NOx emission ratio  seems appealing but this approach was found to suffer significantly from the high uncertainty in the  CO2:NOx emission ratios determined from the same CO2M observations.

Our study shows that CO2M should be able to quantify the emissions of the 400 largest point sources globally with emissions larger than 10 Mt yr-1 that account for about 20 % of global anthropogenic CO2 emissions. However, the mass-balance approach used here has relatively high uncertainties that are dominated by the uncertainties in the estimated CO2 background and the wind speed in the plume, and uncertainties associated with the sparse temporal sampling of the varying emissions. Estimates could be significantly improved if these parameters can be better constrained, e.g., with atmospheric transport simulations and independent observations.

How to cite: Kuhlmann, G., Henne, S., Meijer, Y., Emmenegger, L., and Brunner, D.: Quantifying CO2 emissions of power plants with the CO2M mission, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-3260,, 2021.

Display materials

Display file

Comments on the display material

to access the discussion