Abstract
The ‘Dieselgate’ emissions scandal has highlighted long standing concerns that the performance gap between ‘real world’ and'official’ energy use and pollutant emissions of cars is increasing to a level that renders ‘official’ certification ratings virtually ineffective while misleading consumers and damaging human health of the wider population. This paper aims to explore the scale and timing of historic and future impacts on energy use and emissions of the UK car market. To achieve this aim it applies a bespoke disaggregated model of the transport-energy-environment system to explore the impacts of retrospective and future policy scenarios on the UK car market, trade-offs between greenhouse gas and air quality emissions, and fuel use and associated tax revenues. The results suggest that the impacts on human health of ‘real world’ excess NOX emissions in the UK are significant. Future ‘low diesel’ policies can have significant air quality benefits while showing few (if any) carbon disbenefits, suggesting future car pricing incentives may need to be rebalanced taking more account of effects of local air pollution. Car pricing incentives are however unlikely to transform the car market without additional market changes, industry push, infrastructure investment and policy pull aimed at cleaner, lower carbon vehicles.
Highlights
While real world CO2 emissions have been shown to be on average a third higher (Committee on Climate Change (CCC), 2015b; ICCT, 2014a; TandE, 2015a), NOX emissions can be up to 40 times higher than official certification values and standards operating in the EU (Hagman et al, 2015; ICCT, 2014b; Weiss et al, 2012), the US (Barrett et al, 2015) and China (Lau et al, 2015; Shen et al, 2015)
This paper aims to fill existing gaps in the work going on relating to the assessment of ‘real world’ vs ‘official’ emissions and potential policy responses elsewhere which: (a) ignores the potential tradeoffs between human health and climate change mitigation impacts; (b) lacks detailed analysis of how policy and market signals can change the evolution of the car market; (c) ignores wider fuel and/or vehicle life cycle emissions impacts in comparing different pathways; and (d) lacks investigating the impacts on transport fuel use and associated tax revenues
In terms of carbon emissions the results showed that already in the forward-looking baseline case (REF’) direct emissions of CO2 from cars fell substantially, from the 2015 level of 65 Million tons of CO2 (MtCO2) to 61 MtCO2 in 2020, 53 MtCO2 in 2030 and 45 MtCO2 in 2050.11 While the post-2008 economic downturn and rising fuel costs were major factors underlying the short term fall before 2015 (Fig. 2), the longer-term decrease of about 18% between 2015 and 2030 is largely the result of improvements in fuel efficiency and emissions performance of new cars penetrating the fleet and some fuel switching to hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV), offsetting the overall growth in the demand for car travel
Summary
Concerns that the performance gap between ‘real world’ and ‘official’ energy use and air pollutant emissions of road vehicles is increasing to a level that renders ‘official’ certification ratings virtually ineffective while misleading consumers and damaging human health of the wider population. In the UK, for instance, diesel vehicles accounted for fewer than 1 per cent of cars on the road in 1984 – last year that figure had risen to more than a third, with new registrations totalling about 1.35 million (or half) of all new cars in 2014 (SMMT, 2014). This compares to the almost 1.2 million VW diesel vehicles affected in the UK, and about 11 million VW diesel vehicles worldwide (Sheffield, 2015; Yeomans, 2015)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
