Emission Inventory Prague
Topic of the practice
The City of Prague uses an emission inventory for air quality pollutants which is based on the national air quality emission inventory for the Czech Republic referred to as the Air Pollution and Sources Register (the corresponding Czech acronym is REZZO). The major difference between the national inventory and Prague’s inventory is that Prague’s one is used for city-wide air quality modelling and therefore has temporal and spatial characteristics suitable for such an application.
Good Practice Information
Calculation of emissions for the national inventory generally follows the methodology for emissions calculation that is set out in the EMEP (EEA) air pollutant emission inventory guidebook. Point sources in the emission inventory are represented by measured emissions (where possible) for large sources and calculated emissions for smaller sources. The calculations for these smaller sources are based on fuel consumption and EMEP emission factors. Combustion source characteristics are described by stack height and diameter, flue gas temperature, flow rate and velocity. Source specific information on these sources is provided by plant operators and validated by the Czech National Environmental Inspectorate. Temporal variation of emissions from large combustion sources is accounted for by annual profiles. Sources which have weekly, daily, or irregular shifts in emission profiles are described with a higher temporal resolution and the highest temporal resolution is daily.
Emissions from small sources such as home heating systems are not calculated individually in the national inventory. For the inventory they are calculated over an area using land use and population data and ambient temperature and season. A similar methodology is applied to mobile emissions (e.g cars). Therefore, for Prague's emission inventory the calculation of mobile source emissions includes additional information such as traffic volumes, diurnal emission profiles, locations of tunnels and car-parks and bus depots.
Mobile emissions are then able to be modelled as line sources (for major roads) and area sources (for minor roads).
Evidence of success
Prague's emission inventory (EI) for air quality includes emissions from the national inventory therefore, where possible, the calculation methods for Prague’s emission inventory follow the national rules using the official classifications by source type and using approved calculation methods. This brings consistency to the emissions in both inventories. When compared to the national inventory, more detailed calculations are made for some source groups. These groups include mobile sources (e.g. vehicles on the roads). This is done to allow the dispersion of emissions to be modelled on an hourly basis. The EI allows Prague to keep track of mass-totals of substances released into the air and also, from the dispersion modelling, produce maps of modelled air quality in Prague. This information allows the City of Prague to communicate the state of Prague's air environment to the public.The information also informs city planning and development processes.
Contact details to obtain further information on the practice
Czech Hydrometeorological Institute
Annex completed on: 04-23-2011