Evaluation of parameter-based vehicle emissions targets in the EU

Fuel Economy and gHg standards design series the author would like to thank his colleagues John german, anup Bandivadekar and Joe schultz for their guidance and constructive comments, as well as all icct internal and external reviewers of this paper. ExEcutivE Summary the current carbon dioxide (co 2) emission performance standards for new passenger cars in the European Union are based on vehicle weight. the corresponding regulation (Ec) no 443/2009 defines a long-term target of 95 g/km to be met by 2020 and asks for a review of the exact modalities for reaching this target, including a potential change from mass to another utility parameter, in particular vehicle footprint, for determining emission targets. a list of assessment criteria was developed and applied to an extended list of potential index parameters. only few qualified for further investigation. in particular, it was found that a size-based emission target system would provide several advantages compared to the current weight-based system. in contrast to a weight-based system, under a size-based system emission reductions from vehicle weight reduction are fully taken into account, thereby allowing higher emission reductions and more flexibility for manufacturers in meeting their targets at equal or even lower compliance costs. Furthermore, a size-based target system is less prone to gaming (i.e., manufacturers making changes to the characteristics of their vehicles for the purpose of meeting their targets while emissions stay constant or even increase) and correlates better with vehicle utility than weight. when deciding between vehicle footprint or pan area (shadow) as an index parameter, footprint offers several advantages; in particular, footprint data is already systematically collected under the existing regulation (Ec) no 443/2009. making use of an extensive database of 2009 sales of passenger cars in the European Union, the effects of different target systems on manufacturers and individual vehicles were analyzed. the results show that differences in the required 2009–2020 emission reductions between the most likely versions of a weight and a size-based system amount to a maximum of 2–4 g/km for the main manufacturers. similarly, it was found that none of the major vehicle types would be overly penalized or preferred under any of the systems. Based on these findings it is recommended that not vehicle mass but vehicle size, and preferably footprint, be used as a utility parameter for meeting the 95 g/km target by 2020 and for future European Union co 2 emission targets. curb weight …