Thierry Coosemans

Conventional, Hybrid, or Electric Vehicles: Which Technology for an Urban Distribution Centre?

Freight transport has an important impact on urban welfare. It is estimated to be responsible for 25% of CO2 emissions and up to 50% of particles matters generated by the transport sector in cities. Facing that problem, the European Commission set the objective of reaching free CO2 city logistics by 2030 in major urban areas. In order to achieve this goal, electric vehicles could be an important part of the solution. However, this technology still faces a number of barriers, in particular high purchase costs and limited driving range. This paper explores the possible integration of electric vehicles in urban logistics operations. In order to answer this research question, the authors have developed a fleet size and mix vehicle routing problem with time windows for electric vehicles. In particular, an energy consumption model is integrated in order to consider variable range of electric vehicles. Based on generated instances, the authors analyse different sets of vehicles in terms of vehicle class (quadricycles, small vans, large vans, and trucks) and vehicle technology (petrol, hybrid, diesel, and electric vehicles). Results show that a fleet with different technologies has the opportunity of reducing costs of the last mile.

A valuation of the environmental performance of vehicles: an analysis and comparison of two methodologies

The European Clean Vehicle Directive was introduced in 2009 to create an obligation on public authorities to take into account the impact of energy consumption, carbon dioxide (CO2) emissions and pollutant emissions into their purchasing decisions for road transport vehicles. This should stimulate the market for clean and energy-efficient vehicles and improve transports impact on environment, climate change and energy use. Therefore the so-called ‘Operational Lifetime Cost’ of a vehicle is calculated, divided into the cost for energy consumption, CO2 and pollutant (nitrous oxide, particulate matter, non-methane hydrocarbons) emissions. In Belgium, a different methodology has been developed to calculate the environmental impact of a vehicle, called ‘Ecoscore’, based on a well-to-wheel approach. More pollutants are included compared to the Clean Vehicle methodology, but also indirect emissions are taken into account. In this paper, both methodologies are compared and used to analyze the environmental performance of passenger cars with different fuel types and from different vehicle segments. Similar rankings between both methodologies are obtained; however, the large impact of energy use (and CO2 emissions) in the Clean Vehicle methodology disadvantages compressed natural gas cars, as well as diesel cars equipped with particulate filters, compared to the Ecoscore methodology.

Optimization of Propulsion Systems for Series-Hybrid City Busses through Experimental Analysis

This article describes a methodology for the optimization of hybrid propulsion systems combining an onroad measurement campaign with the development of a simulation tool. This methodology has been applied in particular on a series-hybrid city bus. The experimental set-up and the software tool are presented. The measurement setup is based on a National Instruments-cDAQ data acquisition system, containing a real-time programmable embedded processor. The software model is mainly based on the ‘backwards-looking’ or ‘effect-cause’ method which calculates the energy consumed by a vehicle following a predefined driving cycle by going upstream the vehicle components. Experimental as well as simulated results are presented. The developed simulation tool is assessed and refined by means of the experimental data obtained during the thorough on-road measurement campaign. Suggestions for an improved and more efficient power flow control strategy for series-hybrid city busses are given. - Copyright Form of EVS25.sz