Emissions of nitrogen oxides (NOx) in the Netherlands decreased in 2011, for the first time to a level below the cap set by the European Union for 2010. Hereby, the Netherlands complies with all four national emission ceilings (NEC). In 2010, it already complied with emission ceilings for ammonia (NH3), sulphur dioxide (SO2) and non-methane volatile organic compounds (NMVOC).
This has become apparent from the explanation of Dutch emission data on transboundary air polluting substances in the 2013 Informative Inventory Report (IIR) by the National Institute for Public Health and the Environment (RIVM). For this report, PBL Netherlands Environmental Assessment Agency has contributed to the calculation and reporting of air polluting emissions in the Netherlands.
The report describes emission trends and levels for SO2, NOx, NMVOC, NH3, carbon monoxide (CO), particulate matter (PM), heavy metals and persistent organic pollutants (POPs) in the Netherlands, for the 1990–2011 period. For all these substances, emissions have decreased. The downward trend may be attributed in particular to cleaner fuels, cleaner car engines and to emission reductions in the industrial sectors.
Fewer Lower emission levels of pollutants from old passenger cars
Emission levels related to traffic are calculated by a number of task forces of the Dutch Pollutant Release and Transfer Register (PRTR). New methods for calculating emissions, over the years, have led to results that are ever more accurate. This year, a major improvement was made in emission calculations for passenger cars in the Netherlands. Consequently, the emission levels from cars with petrol engines without catalytic converter appeared to have been lower in recent years than previously estimated. In particular, because these cars on average drove fewer kilometres per year than previously assumed. Statistics Netherlands (CBS) in the past have monitored the kilometres driven by passenger cars in greater detail, and this time by further categorising them according to vehicle age and fuel type. They estimated that, between 2005 and 2010, total NOx emission levels from passenger cars were about 15% lower than estimated last year. NMVOC emission levels were 25% lower than previously estimated.
NOx emission levels from diesel vehicles in the so-called Euro 5 category appear to be higher than previously assumed. The term Euro 5 refers to the European emission standards for pollutants emitted from passenger vehicles and light commercial vehicles. Euro 5 vehicles entered the Dutch market in 2008. Measurements from TNO in 2012 show that NOx emission levels from Euro 5 vehicles are considerably higher than the standard; how much higher depends on road and traffic conditions and driving behaviour. As a consequence, reported NOx emission levels from passenger vehicles in 2010 were 6% higher than reported last year.
Role of PBL Netherlands Environmental Assessment Agency in the national air pollutants inventory
Until 2009, PBL Netherlands Environmental Assessment Agency was the coordinating institute for the Dutch Pollutant Release and Transfer Register (PRTR). This role has since been taken over by the National Institute for Public Health and the Environment (RIVM), while PBL continues to be a member of the various task forces of the Dutch PRTR. The PRTR comprises task forces for specific economic sectors, such as transport, industry and agriculture. Task forces both supply and assess emission estimates, guard the quality and robustness of methods, keep pace with new scientific insights and, where necessary, are responsible for implementing new methods. Involvement is important to PBL, in order to remain up to date on emission developments and to use this knowledge in its outlook studies, assessments, evaluations and calculations of policy options.