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The transport sector is one of the highest greenhouse gas emitters in the EU. The JRC's DIONE model calculates the costs for road transport CO2emission reduction, based on functions associating vehicle emission reduction with their costs (cost curves). This paper describes the development of cost curves for a wide range of additional powertrains and classes of trucks, busses and coaches, and trailers. The model extension is a basis for analyzing the socio-economic impacts of reducing CO2emissions from heavy-duty vehicles.

The monitoring and reporting of CO2emissions of light duty vehicles in Europe and other major markets is based on the New European Driving Cycle and the accompanying test protocol. This procedure has been proven non-representative of real world vehicle operation, fuel consumption and CO2emissions leading to a gap between officially reported emissions and the ones experienced during real world operation. This gap is reported to be increasing with time. To address this issue and improve the certification procedure for pollutant emissions of vehicles over real driving, the new Worldwide Harmonized Light duty vehicle Test Protocol was designed. This new test procedure is expected to provide more realistic emission and fuel consumption results. In this paper a first estimate of the certification-reality gap under the present (2015) conditions is attempted and the impact of the new test procedure is investigated. Tests were performed on three real vehicles over the two cycles which allowed the development of representative simulation models. A detailed simulation matrix was subsequently formulated, taking into account the two tests and expected conditions occurring during real world driving. Results show that for 2013-14 model year European passenger cars the difference in certified and actually emitted CO2emissions for an average European passenger car reaches up to 40 g CO2/km (~32% higher than certification). WLTP introduction is expected to improve the picture, however a shortfall of about 10-15% between official and real world may remain.

This paper presents a new technology-oriented modelling approach for assessing the effect of different technologies and fleet composition on energy consumption/CO2emissions. The methodology follows a hybrid approach between a statistically founded instantaneous emission model and a complete vehicle-simulation model. It makes use of as limited information as possible referring mainly to already available data sources. It is split into two modules, the sampling module where individual vehicles are defined, each one corresponding to a real vehicle present in the fleet, and the simulation module where each vehicle is run in a predefined mission profile. The vehicle simulation model is based on simple longitudinal dynamics featuring an extended-Willans powertrain simulation module. The fleet “generator” module that selects and assigns vehicle characteristics per vehicle is based on existing databases and the annual CO2emissions monitoring database new vehicle registrations in the European market. The implementation code is built so that several thousands of simulations are possible in limited time. In this example, the methodology is applied for assessing the introduction of the new Worldwide Harmonized Test (WLTP) protocol in the European light duty vehicle type approval procedure. A representative fleet of approx. 4,000 vehicles, model year 2013-2014, was defined and run over the existing and forth-coming type approval cycles. Results showed good correlation of fleet-wide predicted CO2emissions against preliminary certification data for year 2014 that were used for validation. Following, the WLTP provisions were introduced and calculations were made with regard to the expected increases in average CO2emissions of the new registrations with the new protocol.