Abstract
Keywords
energetic pathways, comparison, external costs, urban bus.
Abstract
In 1999, ADEME started a national program relating to a comprehensive study on urban transports. Several technical solutions were evaluated to quantify on a real driving condition for buses, on one hand pollutants emissions and fuel consumption, and on the other hand, reliability and cost in real existing fleet.
Main pathways evaluated, using representative driving cycles, are :
- on existing fleet (retrofitting) using fuel modifications (Diesel with water emulsion, Diesel with biofuel content), Diesel particulates filters or NOx reduction system.
- for new vehicles, Diesel Euro4 & 5, NGV, LPG, hybrid, electric buses.
Choosing between all energetic pathways available like Biofuels, NGV, LPG, Diesel…, with their specific advantages (not often easily valorised as pollutions, Green House Gases, noise…) and their inconveniences (costs, practise & expertise changes), presents barriers to decision makers. ADEME aims at overcoming these barriers and promoting renewable energy sources by proposing different comparisons levels and an integrated decision tool that will valorise pollutants emissions in economics terms, add the "classical" economic costs, and will unit all relevant criteria in one easy-touse tool adapted to local conditions.