What does the survey comprise?
To obtain data on the national atmospheric emissions by stationary sources.
Stationary sources. This population includes installations for fuel combustion (generation of heat, power or energy), installations for industrial processes, and other non-mobile activities (such as storage and transfer). The survey comprises the emissions of CO2, CH4, N2O, CO, VOC (non-methane), NH3, NOx, SO2, and PM10.
First year of survey
Yearly. StatLine provides data on 1990, 1995, and from 2000 onwards yearly.
Provisional figures are published 8 months after the year under review; definite are published about 17 months after the year under review.
The results of the survey are published in three StatLine tables (in English):
1. Emissions to the atmosphere: the actual emissions of all 9 substances (including by mobile sources).
2. IPCC emissions to the atmosphere: 3 greenhouse gases (CO2, CH4, N2O) calculated according to the IPCC protocol standards.
3. NEC emissions to the atmosphere: 5 substances which cause large scale air pollution (mainly substances causing acidification): non-methane VOC, NH3, NOx, SO2 and PM10 calculated according to the NEC standards.
Results are also published via the public website of the Dutch Emission Registration. An abstract of the emission data is also included in the CBS/PBL Compendium voor de Leefomgeving (Compendium for the human environment).
How is the survey carried out
The survey uses both an external registration (annual environmental enterprise reports) and Statistics Netherlands data. The survey takes place within the framework of the Dutch Emission Registration Project. Besides Statistics Netherlands (CBS) the following institutes participate in this project: the Dutch Environmental Assessment Agency (PBL), the Agricultural Economics Institute (LEI) and Alterra (both parts of Wageningen University and Research Centre), the Water Department of the DG for Public Works and Water Management, SenterNovem and TNO. The StatLine tables also include research results of the partners in this project.
• The greenhouse gas emissions from stationary sources are based on fuel consumption figures published in the National Energy Balance Sheet of Statistics Netherlands. Emission volumes are determined by multiplying these activity data with emission factors. For CO2 the emission factors from the ‘National list of fuels and standard CO2 emission factors’ or enterprise specific data are applied. These data originate for instance from the annual environmental reports. The methane and N2O emission factors per fuel type are derived from the monitoring protocol for stationary combustion fossil fuels in the framework of the National System for monitoring and reporting on greenhouse gases (see www.broeikasgassen.nl).
• The emissions of other substances are determined on the basis of data from annual environmental reports and relevant emission factors. Upscaling to national totals takes place with the aid of additional CBS production and energy figures.
The registration of annual environmental report comprises about 350 enterprises.
Checking and correction methods
Checking takes place by a trend analysis of the basic data from the individual enterprises published in their annual environmental reports. After the calculations a joint trend analysis is performed in the framework of the Emission Registration, in which the emissions per substance are assessed on plausibility and consistency by the various parties participating in the Emission Registration.
How accurate are the results?
• The quality of emission figures calculated from annual environmental report data, depends strongly on the quality of the environmental reports. If there is any doubt about the quality of an environmental report, the data concerned are not used in the emission calculations.
• Because of the many different data sources used and determination methods for the basic data on the one hand and the complexity of the calculation on the other hand, it is not possible to express the accuracy of the various emission data in exact figures.
• The emission calculation method was changed from registration year 1999 onwards, because of the introduction of the compulsory annual environmental report as the basis for the data collection. This change did not lead to demonstrable breaks in series for the presented pollutants.
• Since 2004 a new method is applied for the calculation of greenhouse gas emissions. This method is no longer based on the annual environmental reports but mainly on energy statistics form Statistics Netherlands. In addition, secondary information is used when necessary, particularly from annual environmental reports in which large industrial enterprises report their emissions, in order to determine enterprise-specific emission factors. In that case the data from these reports is compared with the data from the energy statistics. In order to be able to calculate CO2 emissions on the basis of energy statistics, the usefulness and consistency of the figures concerned were investigated in 2004. All years under review from 1990 onwards were recalculated according to this new method, so no break in series occurred.
Plausibility control by means of a trend analysis. The determination of the emission figures takes place within the cooperation framework of the Dutch Emission Registration Project.