Power plants burning fossil fuels still generate almost half of the electricity in the EU. Photo: Flickr.com / Spiros Vathis CC BY-ND

Set strict emission limits for power plants

It is now up to the member states to set ambitious emission standards for large combustion plants, in line with the strictest recommended air pollution limit values.

A recent analysis by the European Environment Agency (EEA) shows that applying strict but realistic emission limits for the power sector could cut emissions of key air pollutants by 79–91 per cent by 2030.

Adopted in July 2017, the new EU air pollution standards are set out in a reference document for best available techniques (BREF) for large combustion plants under the 2010 Industrial Emissions Directive (IED).

The EEA analysis1 has looked at the potential benefits of an ambitious implementation of the new BREF emission limits in the EU power sector. The BREF document sets a range of emission limits that member states must use for emission permits right now for new plants, and by 2021 at the latest for existing plants. The upper (less strict) emission limits represent the absolute minimum member states must do, while the lower (more strict) emission limits are a reference for more ambitious targets.

According to the EEA, implementing the upper emission limits of the new requirements would, by 2030, result in emission cuts of 66 per cent for sulphur dioxide (SO2), 56 per cent for particulate matter (PM) and 51 per cent for nitrogen oxides (NOx), compared with 2016 emissions. However, implementing the more ambitious targets would result in significantly more substantial emission reductions of 91 per cent for SO2, 82 per cent for PM and 79 per cent for NOx (see Figure).

The additional NOx emission reductions associated with achieving the more ambitious level of implementation are, for 2030 alone, comparable to the lifetime NOx emissions of 220,000 modern (average Euro 6) diesel cars on European roads (assuming a lifetime mileage of 150,000 km).

Power plants burning fossil fuels still generate almost half of the electricity in the EU and are responsible for the release of more than half of the total SO2 emissions, 15 per cent of NOx emissions and 4 per cent of PM emissions, as well as other toxic pollutants, such as mercury.

Emissions of SO2 and PM from power plants in the EU have decreased by more than three-quarters since 2004, primarily because of environmental regulation, according to a study2 commissioned by the EEA and carried out by environmental consultants Trinomics.

The study looked at the period between 2004 and 2015 and found that, at EU level, the most important factor in reducing emissions of SO2, NOx and PM from electricity-generating large combustion plants (LCPs) was improvements in the emission factor – i.e. the quantity of pollutant emitted per unit of fuel consumed for a given pollutant and fuel type.

In particular, for SO2 and PM, changes in emissions factors would have resulted in 71 and 75 per cent decreases in emissions respectively, had all other factors remained constant. For both these pollutants, the most rapid period of decline in emissions was between 2007 and 2008, which coincides with implementation of the stricter SO2 standards of the LCP Directive in 2008.

For NOx, the emission factor effect was smaller, but it was still the most important single factor, contributing to a 38 per cent decrease in emissions.

According to the study, other important factors affecting emissions at the EU level as well as for individual member states, were changes in the energy mix of electricity generation, in the energy intensity of the economy, and in the degree of electrification of final energy consumption:

  • At the EU level, a general reduction in the energy intensity of economic sectors contributed to a decrease in emissions of between 6 and 11 per cent for all four pollutants.
  • An overall rise in economic activity at the EU level contributed to a small increase (4–7%) in emissions of the pollutants studied. There was also an increase in the degree of electrification that increased the demand for electricity from LCPs, which contributed to a rise in emissions of between 6 and 9 per cent, depending on the pollutant.
  • Finally, shifts in the energy mix of electricity generation helped to reduce emissions at the EU level, by 13, 15, 12 and 17 per cent for SO2, NOx, PM and CO2 respectively. The main driver of this effect was a small decline in the use of “other solid fuels” (i.e. coal) in electricity generation (from 31 to 25 per cent share of generation).

The report concludes that, overall, the most important driver of reductions in emissions from electricity-generating LCPs was the change in the environmental performance of coal-burning LCPs. The LCP Directive impacted this change primarily in two ways: firstly, through installation of abatement technologies so that plants could comply with the Directive’s emission limit values by 2008; and secondly, through the closure of LCPs that were unable to meet those emission limit values.

LCPs that “opted-out” (i.e. using Article 4(4) of the Directive) closed at various times during the period 2008–2015, because retrofitting abatement technologies was not economically viable for many of these plants, which were often near the end of their operational lifespan.

After some years of levelling off after 2010, emissions from LCPs began to decrease again after 2013, probably in anticipation of the stricter emission limit values imposed by the Industrial Emissions Directive, which fully came into force from 2016.

Christer Ågren

EEA Briefing: “Greening the power sector: benefits of an ambitious implementation of Europe’s environment and climate policies” (December 2018). https://www.eea.europa.eu
1 “Emission scenarios for large combustion plants under the IED regime” (November 2018). Eionet Report — ETC/ACM 2018/16. Link: https://acm.eionet.europa.eu/reports/EIONET_Rep_ETCACM_2018_16_IEDregime...
2 “Decomposition analysis for air pollutants and CO2 emissions from large combustion plants across Europe” (March 2018). By Trinomics/Aether. Link: http://www.aether-uk.com/CMSPages/GetFile.aspx?guid=14ca8d73-614e-42db-8...

Figure: Total projected annual emissions from large combustion plants (in kilotonnes per year) in 2021, 2025 and 2030 for SO2, NOx and dust in case current IED limits, upper or lower levels of the new requirements (LCP BREF) are used to set permit conditions.


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