Regulated and Non-Regulated Emissions from Euro 6 Diesel, Gasoline and CNG Vehicles under Real-World Driving Conditions

The transport sector is one of the main sources air pollutants. Different exhaust after-treatment systems have been implemented over the years to control the emissions of criteria pollutants. However, while reducing the emissions of the target compounds these systems can lead to the emissions of other pollutants and/or greenhouse gases such as NH3 or N2O. Following the implementation of the Real Driving Emissions (RDE) test procedure in the EU, vehicles have been equipped with more complex after-treatment configurations. The impact that these technologies may have on the emissions of non-regulated pollutants during real-world driving have not been evaluated until now. In the current study we present the on-road emissions of a series of non-regulated pollutants, including NH3, N2O, CH4 and HCHO, measured with a portable FTIR from a series of Euro 6d, Euro 6c and Euro 6d-TEMP, gasoline diesel and compressed natural gas (CNG) vehicles during real-world testing. The obtained results show that it is possible to measure N2O, NH3, CH4 and HCHO during on-road operation. The results also highlight the importance of the measurement of the emissions of these pollutants during real-world driving, as the emissions of NH3 (a particulate matter precursor) and those of N2O and CH4 (green-house gases) can be high from some vehicle technologies. NH3 emissions were up to 49 mg/km for gasoline passenger cars, up to 69 mg/km for the CNG light-commercial vehicle and up to 17 mg/km a diesel passenger car equipped with a selective catalytic reduction system (SCR). On the other hand, N2O and CH4 emissions accounted for up to 9.8 g CO2 eqv/km for a diesel passenger car equipped with a combination of diesel oxidation catalysts (DOC), lean NOx traps (LNT), SCR and possibly an ammonia slip catalyst ASC

Effect of Biodiesel Fuels on Pollutant Emissions from EURO 3 LD Diesel Vehicles (1)

Transport is a key factor in modern economies. However, the EU transport system is currently not sustainable, and in many respects moving away from sustainability rather than towards it. The European Environment Agency highlights in particular the sector's growing CO2 emissions that threaten the EU meeting its target under the Kyoto protocol. Transport also represents a key challenge to sustainability in terms of depletion of resources and European competitiveness, safety and security concerns, especially due to the monolithic reliance on a single energy source. As stated in the Commission’s November 2000 Green Paper on security of supply, in 1998 energy consumption in the transport sector was to blame for 28 % of emissions of CO2, the leading greenhouse gas. In particular, road transport alone accounts for 84 % of the CO2 emissions attributable to transport. Furthermore, in terms of security of energy supply, there is growing concern for the current situation of transport sector that depends on crude oil for more than 99%. In the above mentioned Green Paper the European Commission has also identified the measures to tackle these problems and, among them, one the most important is the promotion of alternative fuels; the ambitious target that has been proposed by the Commission is to replace 20% of conventional fuels with substitute fuels by 2020. According to the Commission White Paper “European transport policy for 2010: time to decide” the most promising forms are biofuels in the short and medium term, natural gas in the medium and long term and hydrogen in the very long term. On the basis of the above mentioned Papers, in 2003 the European Union has adopted two Directives, the EC/2003/30 and the EC/2003/96, with the overall objective of promoting the use of biofuels. The first Directive set the targets for market share of biofuels for 2005 (2% in terms of energy content) and 2010 (5.75%); the second Directive set the framework for tax incentives for the promotion of biofuels. Biodiesel is currently the most produced biofuel in Europe: the production in 2003 was about of 1500000 (EU25) tons with an increase of more than 32% compared to the 2002 figure. Within this policy framework, the Joint Research Centre and the European Biodiesel Board have decided to cooperate to investigate the effect of biodiesel on pollutant emissions from diesel engines. In particular, in this report the effect of biodiesel fuels produced from different raw materials on the regulated emissions from light duty diesel vehicles are compared to the effect on other regulated and unregulated pollutants.JRC.H.4-Transport and air qualit

The role of cognitive reserve and clinical symptoms in the association between genetic liability for educational attainment and functioning in first-episode psychosis: a mediation analysis

Background: Polygenic risk scores for educational attainment (PRSEA), cognitive reserve (CR), and clinical symptoms are associated with psychosocial functioning in first-episode psychosis (FEP). Nevertheless, the mechanisms underlying their complex interaction is yet to be explored. This study aimed to assess the mediating role of CR and clinical symptoms, both negative (NS) and positive (PS), on the interrelationship between PRSEA and functionality, one year after a FEP.Methods: A total of 162 FEP patients underwent clinical, functional, and genetic assessments. Using genome-wide association study (GWAS) summary results, PRSEA were constructed for each individual. Two mediation models were explored. The parallel mediation model explored the relationship of PRSEA with functionality through CR and clinical symptoms, NS, and PS. The serial mediation model tested a causal chain of the three mediators: CR, NS and PS. Mediation analysis was performed using the PROCESS function V.4.1 in SPSS V.22.Results: A serial mediation model revealed a causal chain for PRSEA > CR > NS > Functionality (β=-0.35, 95%CI [-0.85, -0.04], pConclusions: Both CR and NS mediate the relationship between PRSEA and functionality at one-year follow-up, using serial mediation analysis. This may be relevant for prevention and personalized early intervention to reduce illness impact and improve functional outcomes in FEP patients.</p

Source Apportionment of Ozone Precursor VOCs in Urban Atmospheres by Receptor Modelling

The chemical mass balance (CMB) and positive matrix factorization (PMF) receptor models have been used to identify and apportion the dominating sources for individual C2-C9 hydrocarbons specified in the European Ozone Directive 2002/3/EC in Milan (I) and Lille (F). A new approach estimating the uncertainties in the ambient concentrations as a function of the analytical precision and the atmospheric half-lives of the VOCs gave results which compared well for both receptor models and give a good insight into the emission sources for ozone precursors. In this conference proceeding short-paper a detailed discussion of the results obtained for Milan is presented. Data and results for Lille will be discussed in full in the oral presentation at the 5th International Conference on Urban Air Quality, 29-31 March 2005, Valencia.JRC.H.4-Transport and air qualit

Effect of Low Ambient Temperature on Emissions and Electric Range of Plug-In Hybrid Electric Vehicles

Plug-in hybrid electrical vehicles (PHEVs) are generally considered to be a cleaner alternative to conventional passenger cars. However, there is still very limited information available regarding criteria pollutant emissions from these vehicles. This paper shows, for the first time, the emissions of criteria pollutants, unregulated pollutants, and CO2 and also electric range from two very different PHEVs, one Euro 6 parallel plug-in hybrid and one range-extended battery electric vehicle (BEVx), applying the new world harmonized light-duty test procedure at ambient temperatures equal to 23 and −7 °C. The impact of using a cabin air heating system on vehicle electric range and emissions at cold temperature has also been studied. Cold ambient temperatures and, to a larger extent, the use of heating systems have been shown to lead to a pronounced negative impact on emissions and shorter electric ranges. Results also show that modern PHEVs can emit similar, or even higher, levels of pollutants (e.g., particle number) as Euro 6 conventional gasoline and diesel vehicles

Chemical Speciation of PM (PAH, Heavy Metals, Trace Elements)

Abstract is not availableJRC.H.4-Transport and air qualit

Effect of Water/Fuel Emulsions and a Cerium-based Combustion Improver Additive on HD and LD Diesel Exhaust Emissions

One of the major technological challenges for the transport sector is to cut emissions of particulate matter (PM) and nitrogen oxides (NOx) simultaneously from diesel vehicles to meet future emission standards and to reduce their contribution to the pollution of ambient air. Installation of particle filters in all existing diesel vehicles (for new vehicles, the feasibility is proven) is an efficient but expensive and complicated solution; thus other short-term alternatives have been proposed. It is well known that water/diesel (W/ D) emulsions with up to 20% water can reduce PM and NOx emissions in heavy-duty (HD) engines. The amount of water that can be used in emulsions for the technically more susceptible light-duty (LD) vehicles is much lower, due to risks of impairing engine performance and durability. The present study investigates the potential emission reductions of an experimental 6% W/D emulsion with EURO-3 LD diesel vehicles in comparison to a commercial 12% W/D emulsion with a EURO-3 HD engine and to a Ceriumbased combustion improver additive. For PM, the emulsions reduced the emissions with -32% for LD vehicles (mass/km) and -59% for the HD engine (mass/ kWh). However, NOx emissions remained unchanged, and emissions of other pollutants were actually increased for the LD vehicles with +26% for hydrocarbons (HC), +18% for CO, and +25% for PM-associated benzo[a]pyrene toxicity equivalents (TEQ). In contrast, CO (-32%), TEQ (-14%), and NOx (-6%) were reduced by the emulsion for the HD engine, and only hydrocarbons were slightly increased (+16%). Whereas the Cerium-based additive was inefficient in the HD engine for all emissions except for TEQ (-39%), it markedly reduced all emissions for the LD vehicles (PM -13%, CO -18%, HC -26%, TEQ -25%) except for NOx, which remained unchanged. The presented data indicate a strong potential for reductions in PM emissions from current diesel engines by optimizing the fuel composition.JRC.H.4-Transport and air qualit

Chemical Characterization of Main Sources For Receptor Modeling

See attached documentJRC.H.4-Transport and air qualit