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You are here: Home / Data and maps / Indicators / Nitrogen oxides (NOx) emissions / Nitrogen oxides (NOx) emissions (APE 002) - Assessment published Dec 2011

Nitrogen oxides (NOx) emissions (APE 002) - Assessment published Dec 2011

Generic metadata

Topics:

Air pollution Air pollution (Primary topic)

Environment and health Environment and health

Industry Industry

Tags:
air quality | csi | nox | air emissions | nitrogen | air pollution indicators | pollution
DPSIR: Pressure
Typology: Performance indicator (Type B - Does it matter?)
Indicator codes
  • APE 002
Dynamic
Temporal coverage:
1990-2010
 
Contents
 

Key policy question: What progress is being made in reducing emissions of NOx?

Key messages

  • EEA-32 emissions of nitrogen oxides (NOX) have decreased by 41% between 1990 and 2009. In 2009, the most significant sources of NOX emissions were the ‘Road transport’ sector (38%), ‘Energy production and distribution’ sector (22%), ‘Commercial, institutional and households’ sector (15%) and the ‘Energy use in industry’ sector (13%).
  • The largest reduction of emissions in absolute terms since 1990 has occurred in the road transport sector. These reductions have been achieved despite the general increase in activity within this sector since the early 1990s and have primarily been achieved as a result of fitting three-way catalysts to petrol fuelled vehicles. However, ambient urban concentrations of NO2 in EU-27 countries in recent years have not fallen by as much as reported emissions. Since 2002, NO2 average annual mean concentrations at urban background sites have fallen by just 9 %, as indicated in CSI 004, during which time the reported NOX emissions for the EU-27 decreased by 23%. This discrepancy may be a result of a general under-estimation of the effect of catalytic degradation in newer cars, in which case a number of member states’ NOX emissions could be significantly higher than currently calculated.
  • In the electricity/energy production sector reductions have also occurred, in these instances as a result of measures such as the introduction of combustion modification technologies (such as use of low NOX burners), implementation of flue-gas abatement techniques (e.g NOX scrubbers and selective (SCR) and non-selective (SNCR) catalytic reduction techniques) and fuel-switching from coal to gas.
  • The National Emission Ceilings Directive (NECD) specifies NOX emission ceilings for Member States that must be met by 2010. In general, the newer EU Member States have made substantially better progress towards meeting their respective NOX ceilings than the older Member States of the EU-15. Ten of the twelve post-2004 Member States had already reduced their 2009 emissions beyond what is required under the NECD, with the remaining two reporting NOX emissions less than 2% above the NECD target . In contrast, only four of the EU-15 Member States reported emissions for 2009 within their respective national ceilings. Thus many Member States required a significant reduction of NOX emissions to have been made in 2010 if they are to meet their obligations under the NECD. Of the three non-EU countries having emission ceilings set under the UNECE/CLRTAP Gothenburg protocol (Liechtenstein, Norway and Switzerland) only for Switzerland were emissions in 2009 below the level of their 2010 ceiling.
  • Environmental context: NOX contributes to acid deposition and eutrophication. The subsequent impacts of acid deposition can be significant, including adverse effects on aquatic ecosystems in rivers and lakes and damage to forests, crops and other vegetation. Eutrophication can lead to severe reductions in water quality with subsequent impacts including decreased biodiversity, changes in species composition and dominance, and toxicity effects. It is NO2 that is associated with adverse affects on human health, as at high concentrations it can cause inflammation of the airways. NO2 also contributes to the formation of secondary particulate aerosols and tropospheric ozone in the atmosphere - both are important air pollutants due to their adverse impacts on human health.

Change in emissions of nitrogen oxides compared with the 2010 NECD and Gothenburg protocol targets (EEA member countries)

Note: The reported change in nitrogen oxide emissions (NOx) for each country, 1990-2009, in comparison with the 2010 NECD and Gothenburg protocol targets.

Data source:
Downloads and more info

Distance-to-target for EEA member countries

Note: The distance-to-target indicator shows how current emissions compare to a linear emission reduction 'target-path' between 1990 emission levels and the 2010 emission ceiling for each country. Negative percentage values indicate the current emissions in a country are below the linear target path; positive values show that current emission lie above a linear target path to 2010.

Data source:
Downloads and more info

Key assessment

EEA-32 NOX emissions have decreased by 41% between 1990 and 2009. The majority of EEA-32 countries have reported lower emissions of NOX in 2009 compared to 1990. The exceptions to this are Turkey (a 34% increase between 1990 and 2009), Cyprus (17%), Greece (14%), Malta (7%), Portugal (2%). National totals reported by Luxembourg and Hungary have also increased greatly from 1990 to 2009 (by factors of 118.7 and 20.6 respectively), due to the inclusion of sectors for which emissions were not reported in 1990; ‘Industrial processes’ emissions reported in CRF data represent over 99% of NOX in Hungary in 1990, and 100% in Luxembourg from 1990-2005, whilst in 2009 LRTAP submissions they represent 4% and 0% in Hungary and Luxembourg respectively.

The recession that commenced mid-2008 played a key role in the emission reduction of NOX emissions between 2007 and 2009, by reducing the level of industrial activities etc across Europe. Total emissions reduced by 15% between these two years, compared to a 4% reduction between 2005 and 2007.

In general, the newer Member States of the European Union have made substantially better progress towards meeting their respective NOX ceilings than the older EU-15 Member States. Ten of the twelve post-2004 Member States have already reduced emissions beyond what is required under the NECD, and two reported NOX emissions less than 2% above the NECD target in 2009. In contrast, only four EU-15 Member States had 2009 emissions within their respective national ceilings.

Emissions reported in 2009 indicate that many Member States are not considered to be on track towards meeting their obligations under the NECD. In particular Luxembourg, Austria, Ireland, Spain, and France would require significant (>10%) reductions in NOX emissions to have been made in 2010 if they were to meet their obligations under the NECD. As noted above, emissions have actually increased in seven countries during the period 1990 to 2009, despite all countries having obligations to reduce emissions under the NECD and Gothenburg Protocol. Since 2005 however emissions have fallen in all but one of these countries, indicating that by 2009 some progress had been made towards moving to their NECD ceiling directive limits.

Iceland, Lichtenstein, Norway, Switzerland and Turkey are not members of the European Union and hence have no emission ceilings set under the NECD. However, Norway and Switzerland have ratified the UNECE LRTAP Convention’s Gothenburg Protocol, requiring them to reduce their emissions to the agreed ceiling specified in the protocol by 2010. Liechtenstein has also signed, but not ratified the protocol. While Switzerland has reported emissions in 2009 that were lower than their ceiling, neither Liechtenstein nor Norway has yet met their national ceilings, and thus must still make significant reductions in order to ensure compliance.

The NECD and Gothenburg protocol are currently being reviewed. The revision of the NECD is part of the implementation of the Thematic Strategy on Air Pollution, and a proposal for a revised directive is expected by 2013. A proposal for a revised Gothenburg protocol is presently under international negotiation. The revised protocol is expected to include emission ceilings to be met by 2020 for the four already regulated substances (NOX, NMVOCs, SOX and NH3) and in addition for primary emissions of PM2.5.

Specific policy question: How do different sectors and processes contribute to emissions of NOx?

Sector share of nitrogen oxides emissions (EEA member countries)

Note: The contribution made by different sectors to emissions of nitrogen oxides.

Data source:
Downloads and more info

Change in nitrogen oxides emissions for each sector between 1990 and 2009 (EEA member countries)

Note: Percentage change in nitrogen oxide (NOx) emissions for each sector between 1990 and 2009.

Data source:
Downloads and more info

Contribution to total change in nitrogen oxides emissions for each sector (EEA member countries)

Note: The contribution made by each sector to the total change in nitrogen oxide (NOx) emissions between 1990 and 2009.

Data source:
Downloads and more info

Specific assessment

Reductions of NOX have occurred in all economic sectors apart from the ‘Solvent and product use’ sector, where emissions have increased by almost seven-fold during this period, though in absolute terms this sector makes an insignificant contribution to the total NOX emissions. The three sectors responsible for the vast majority of the decline in NOX emissions are 'Road transport' (contributing 43% of the total reduction in NOX emissions reported by countries), 'Energy production and distribution' (contributing 26%), and 'Other' (contributing 17%).

Significant reductions have occurred in the 'Road transport' sector since the early 1990s, with an overall 44% decline in emissions between 1990 and 2009. This has been achieved despite the general increase in transport activity within this sector over the period. The emission reductions have primarily been achieved as a result of fitting catalysts to vehicles (driven by the legislative 'Euro' standards). However, across Europe there is also an increasing awareness of the contribution made to NOX pollutant emissions by national and international ship traffic (a more detailed discussion of this issue is contained in the TERM indicator fact sheet TERM03 - Transport emissions of air pollutants).

Emissions of NOX have also declined in the 'Energy production and distribution' sector (45% reduction between 1990 and 2009). In the electricity/energy production sector this has been achieved through the implementation of measures such as combustion modification, introduction of flue-gas abatement techniques and a fuel-switching from coal to gas. One of the most common forms of combustion modification is to use low NOX burners, which typically can reduce NOX emissions by up to 40%. Flue gas treatment techniques (e.g. NOX scrubbers and selective (SCR) and non-selective (SNCR) catalytic reduction techniques) can also be used to remove NOX from the flue gases. Emissions of NOX are higher from coal-fired power plants than from gas-fired plants as a result of coal containing significant amounts of nitrogen (unlike gas) and their less efficient combustion processes.

The newer Member States of the European Union have in a number of cases also undergone significant economic structural changes since the early 1990s which has led to a general decline in certain activities which previously contributed to high levels of NOX emissions e.g. heavy industry and the closure of older inefficient power plants.

Data sources

More information about this indicator

See this indicator specification for more details.

Contacts and ownership

EEA Contact Info

Martin Adams

Ownership

EEA Management Plan

2011 1.1.2 (note: EEA internal system)

Dates

Frequency of updates

Updates are scheduled every 1 year in October-December (Q4)
Document Actions
European Environment Agency (EEA)
Kongens Nytorv 6
1050 Copenhagen K
Denmark
Phone: +45 3336 7100