The consortium "The Co-Nordic Natural Gas Bus Project" was formed to stage a development project whose goal was to investigate whether "significantly improved exhaust emissions" could be attained using natural gas or biogas as the motor fuel in city buses. The quantifying of these significant improvements was set a level comparable to emissions from a modern gasoline-driven passenger car equipped with a catalyst. The requirements were set in accordance with US-FTP measuring methods g/k Wh. In the technical sense, there are two methods which may be employed to reduce exhaust emissions: 1) Three- way catalyst technology (TWC), 2) Leanburn technology (L/B). Saab- Scania Company expressed interest in TWC technology, whereas Volvo Bus Corporation was more interested in the L/B technique. Eight laboratories were contacted. Ricardo (TWC) and SwRI (L/B) submitted the most credible bids, and were consequently selected. One of the main reasons for choosing these was their ability to measure results in accordance with the FTP method. Significantly improved exhaust emissions have been proven as follows: CO: 1.36; HC: 1.48; NOx; 2.46 ; particles: 0.02. Engine adaptation information and expertise obtained during the course of the project have been transferred to manufacturers and research institutes in the Nordic countries. Originally, the consortium planned to drive the project so that manufacturers would want to assume control of continued engine development sometime in 1993-94. The manufacturers, however, assumed this role as early as 1991, and the original introductory small-scale tests planned for 1991 may now be staged with more commercial, realistic objectives in mind. The exhibited potentials, taken from an exhaust emissions/energy efficiency point of view, provide the incentive to continue engine development/research, to demonstrate these low emissions levels in practical operations. (A)

  • Corporate Authors:


    STOCKHOLM,   Sweden  S-111 20
  • Authors:
    • EKELUND, M
    • EGNELL, R
  • Publication Date: 1992


  • English

Media Info

  • Features: References;
  • Pagination: 83 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00664809
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • Files: ITRD
  • Created Date: Sep 9 1994 12:00AM