CDT Studentship in Modelling real-world vehicle emissions of greenhouse gases and air quality

This project will build on an existing collaboration with Emissions Analytics (our CASE partner) in analysing real-world measurements of vehicle emissions and exceedances of prescribed emission standards for both CO2 and NOx. Real-world vehicle fuel efficiency is consistently worse than advertised to the consumer. Furthermore, real-world emissions of NOx from the newest Euro 6 diesel cars have shown high variability between different vehicle manufacturers and models. While some vehicles have been shown to meet EC standards, others have emissions that are up to 15 times the standard, with important implications for air quality and development of government policy (as highlighted by the recent VW publicity). Moreover some vehicles show a high proportion of NOx emitted as primary NO2 which is not regulated, and it is the concentrations of NO2 rather than the total NOx that are of concern for human health- a factor that is generally overlooked.

The aim of this studentship will be to explore how real-world emissions data of different vehicles collected by Emissions Analytics can be used to define and explain the variation in emissions between different vehicles and technologies, and the role of driving behaviour. The number of vehicles (over 1000) and different technologies that this studentship will have access to is unprecedented and therefore represents a significant opportunity. Emissions, engine and GPS data collected at 1 Hz captures peak emission events that occur during acceleration or steep slopes along routes. This will be used to compare to existing instantaneous vehicle emissions modelling techniques based on engine loading and develop advancements to these models. Detailed information will be gathered on emissions control technologies deployed on the different vehicles and their configuration. It is also hoped to extend this analysis to a wider range of vehicles, including new direct-injection petrol engines, hybrids and heavier vehicle classes.

Working with the Integrated Assessment Unit in the Centre for Environmental Policy the observed emissions will also be compared with those currently used in air pollution modelling. It is hoped that the emissions model developments will inform the next generation of national inventories of greenhouse gases and air quality pollutants. The effects of real-world emissions on pollutant concentrations will be explored using the UKIAM model of Imperial College applied to London for different vehicle emission scenarios.