Project: NOx Modelling Tools and Heathrow Scenarios

Reference: AED 0809

Last update: 01/04/2010 10:28:52


This project has 3 tasks. Two of these were to gain additional evidence on air quality limits around Heathrow to enable the SoS to make a statement to parliament on Britain's transport infrastructure.

The other task involved studies and calculations of local air quality to support the work of the Committee on Aviation Environmental Protection (CAEP)


The tasks in relation to Heathrow were (a)additional scenarios on air quality modelling of segregated mode at Heathrow in 2030 required for comparison with third runway scenarios already conducted and (b) air quality modelling of impacts of the new road traffic emission factors for different scenarios for comparison with previously modelled scenarios.

The task in relation to CAEP was to contribute expertise and data into the modelling groups of CAEP


No contractors specified.

Contract details

Cost to the Department: £64,000.00

Actual start date: 01 December 2008

Actual completion date: 14 January 2010

Summary of results

  1. In relation to Heathrow air quality modelling of new road traffic emission factors, involved sensitivity tests carried out in late 2008 to explore the extent to which adopting the latest Euro 5&6 vehicle emission standards would potentially impact on the earlier air quality results. Using the 2015 mixed mode scenario results suggested that adopting the latest Euro standards would have been likely to have reduced the residual NO2 exceedences to around four properties in a 2015 mixed mode scenario.

    The additional scenarios on air quality modelling of segregated mode at Heathrow on 2030 was used to inform the Heathrow Equalities Impact Assessment so these could be taken into account in their assesment.

    For the Committee on Aviation Environmental Protection (CAEP) the potential global impacts of stringency changes were investigated and predictions made of the interdependency of NOx emissions with CO2 emissions and noise. Ten stringency options were assessed, for 2016, 2026 and 2036, using two stringency introduction dates, 31 December 2012 and 31 December 2016.

    A summary of the results is as follows
    - The NOx emissions below 3000 feet reduced by 1.4% to 9.8% relative to the no stringency case for the same year, depending on the severity of the stringency option.
    - The maximum overall potential increase in total fuel burn ranged from 0.01% to 0.19% relative to the no stringency case for the same year
    - There was no noise trade off associated with any stringency option