Abstract

This paper analyses what post 2020 targets may be necessary for the European CO2 legislation for passenger cars in order to reach the overall sectoral goal of 60% reduction of transport's greenhouse gas emissions by 2050 relative to 1990, as defined in the European Commission's White Paper. The required target levels are found to depend strongly on the contribution that passenger cars need to make to reaching the overall target, on the assumed growth of passenger car mobility, and on the extent to which biofuels could be available for fuelling passenger cars. To what extent electric vehicles and other low emission vehicles such as plug-in hybrids and fuel cell electric vehicles are needed to meet the post-2020 targets depends on the target level and on the minimum CO2 emissions that can be reached in conventional vehicles. Almost all assessed scenarios, require significant amounts of low emission vehicles to be sold from 2030 or 2035 onwards. Electric and plug-in vehicles are in the early stage of market introduction now, but developments are fragile could end up in a 'valley of death'. Defining a sufficiently low passenger car CO2 target for 2025 may be an effective instrument to motivate manufacturers to continue their efforts in the marketing and further development of these vehicles. This is important for maintaining the momentum of the transition towards large-scale application of low CO2 emitting vehicles. Document type: Article

Abstract

Comparisons of measured and model-predicted atmospheric copper concentrations show a severe underestimation of the observed concentrations by the models. This underestimation may be (partly) due to underestimated emissions of copper to air. Since the phase out of asbestos brake lining material, the composition of brake lining material has changed and may contain up to ∼15% copper. This makes brake wear from vehicles potentially an important source of atmospheric (particulate) copper concentrations. In this paper, we reassess the copper emissions due to exhaust emissions and brake wear from road transport. Overall, our reassessments result in an estimate of total copper emission to air in UNECE-Europe of 4.0-5.5 ktonnes yr-1, which is substantially higher than the previous estimate of 2.8 ktonnes yr-1. Copper concentrations over Europe are calculated with the LOTOS-EUROS model using the revised emission data as model input. The results show that the revised emission estimates are a major step towards gap closure of predicted versus observed copper concentrations in ambient air. Brake wear emissions may be responsible for 50-75% of the total copper emissions to air for most of Western Europe. The hypothesis that road transport is an important source of copper emissions is tested and confirmed by (1) reviewing available literature data of chemically speciated PM data from road tunnel studies and (2) the gradient observed in copper concentrations from ambient PM monitoring going from rural sites to street stations. The literature review and observational data suggest that the majority of the emitted PM10 brake wear particles is in the PM2.5-10 size range. The results of this study indicate that modification of brake lining composition is an important mitigation option to reduce copper exposure of the population in Western Europe. © 2007 Elsevier Ltd. All rights reserved.