The NERVE model («Norwegian Emissions from Road Vehicle Exchaust») provides greenhouse gas and air pollutant emissions from road traffic. The NERVE model is based on bottom-up principles, and it provides emissions at the detail of road link and up to municipality and national level. The model uses road traffic from the Norwegian regional traffic model (RTM) combined with road properties from (NVDB). It uses HBEFA emission factors, and the Norwegian registry of road vehicles and their driving distances based on odometer readings (SSB). Traffic volume and congestion on individual road links are simulated by the regional road traffic model. Annual average daily traffic (ADT) is calculated separately for light, bus and heavy vehicles. Emissions for each road segment are calculated on an hourly basis. HBEFA emission factors for 470 vehicles subsegments and more than 1024 different driving situations (e.g., speed, road-type, slope and congestion) are used with the traffic, segment vehicle distribution and road properties to calculate emissions. The high level of detail makes it also possible to use as a research tool, by constructing different traffic, vehicle or road conditions, from past, predicted or hypothetical situations to calculate emissions.  

NOx emissions from road traffic for the year 2018 over Oslo, illustrating the output from the NERVE emission model

Main Contact person

Henrik Grythe (

Relevant links

Code: GitHub (to come)

Visualization of results:


Weydahl, T., Grythe, H., Haug, T. W.; Høyem, H. (2018) NERVE – Utslipsmodell for veitrafikk. Dokumentasjon av beregningsmodell for klimagassutslipp i norske kommuner. NILU Rapport 28/2018.