Driver navigation systems and lower fuel consumption. A evaluation

Foerarstoed foer laegre braenslefoerbrukning och minskade emissioner: utvaerdering av tvaa system

This licentiate's dissertation emphasizes the possibility of using driver's support which helps the driver to drive fuel efficiently and to lower the level of emissions as much as possible. To estimate the potential of a navigation system for fuel efficient route choices, real trips from a mid-sized Swedish town (Lund) have been used. Out of the modelled fuel consumption of the different road types, a total fuel consumption of every traffic link in the area of study was calculated. The total fuel consumption for the actual route choice was then compared with the most fuel efficient, the shortest and the fastest route choice. In this study, the potential reduction of fuel consumption was also estimated by the information from 120 probe vehicles which give real-time information about disturbances in traffic followed by a recalculation of a new fuel efficient route. In the study where the effects of an accelerator adviser was evaluated drive pattern were recorded of four postal cars in a real traffic environment with and without having an adviser installed. During a drive the accelerator advisor provides the driver a resistance in the accelerator pedal when the acceleration was high. It was possible for the driver to override the resistance whenever necessary. The fuel consumption and emission factors CO, HC and NOx were calculated with a microscopic emission model. The drivers' usage of and acceptance of the acceleration adviser was analysed by doing interviews, questionnaires prior to and after using it as well as by studying the changes in driving patterns. From the search of literature and the two evaluated driver support tools it is apparent that there are good possibilities of using driver's support in order to influence the driving style and route choice to reduce the total fuel consumption and the emissions. The results of the study of low fuel navigation showed that 46 per cent of all trips in Lund, longer than 5 minutes, could have made a more fuel efficient route. These trips could reduce the total fuel consumption by 8.2 per cent which gives that if the gain was distributed on all trips the fuel reduction would be 4 per cent. The study also showed that road classes with a high density of junctions controlled by traffic fights, local streets and the main streets in the city centre also generated high fuel consumption. The estimation of the potential total fuel reduction, by using probe vehicle information of traffic disturbances, gave a total fuel reduction by 0.04 per cent. This is a negligible fuel saving. The evaluation of the effects of an acceleration advisor showed that the amount of time of strong acceleration (more than 1.5m/s2) was reduced when the advisor was installed, which indicates that the advisor has worked and that the test drivers have followed the given advice. It was however not possible to show any significant reduction of fuel consumption more than for a specific route whilst driving with the acceleration advisor. The emissions of CO, HC and NOx did not show any statistic significant difference when the analysis was done on all the driving patterns, with or without an acceleration advisor. It was evident in the interviews that the use of the acceleration advisor varied. Examples of situations when the drivers override the resistance was more frequently appeared to be when the driver felt uneasy about the traffic situation, when the flow of traffic was heavy and when there was a lack of time. A factor that could result in an increase of driver compliance of the advisor was short distance between stops. The results of the questionnaire prior to usage showed that the general opinion of driving with the advisor was 'either or' or 'rather good'. After the log period the attitude towards the acceleration advisor was less positive. Though, in an analysis of the relation between the drivers' general perception of driving with the acceleration advisor and how frequently they have driven with the driver's support showed a tendency of those who had driven more frequently being more positive to the system than those who had merely tested the advisor a few times (A). http://luur.lub.lu.se/luur?func=downloadFile&fileOId=1370102.

Language

  • English

Media Info

  • Pagination: 101p+app
  • Serial:
    • BULLETIN
    • Issue Number: 242
    • Publisher: LUND INSTITUTE OF TECHNOLOGY, DEPARTMENT OF TECHNOLOGY AND SOCIETY, TRAFFIC ENGINEERING
    • ISSN: 1404-272X

Subject/Index Terms

Filing Info

  • Accession Number: 01141052
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • Files: ITRD
  • Created Date: Sep 30 2009 8:58AM