WHERE DOES THE ENERGY GO? A SIMPLIFIED PERSPECTIVE ON FUEL EFFICIENCY IN RAIL FREIGHT TRANSPORTATION

The potential impact of measures intended to reduce fuel use in the operation of mainline freight trains can often be bounded or approximated by relatively simple calculations. In some cases, this may be sufficient to reject options that are intuitively appealing but actually offer very small gains, thereby avoiding expensive simulation or measurement programs. When a potential conservation measure is found to have sufficient promise to warrant detailed examination, preliminary estimates can ensure that further efforts are well-founded and properly structured. In this paper, a standard train-resistance equation and industrywide aggregated data are used to assess the effect of various equipment characteristics and operating scenarios on fuel use for a baseline case (a 4700-ton, 66-car train traveling at 40 mph) in order to develop useful approximations. Emphasis is on examination of the specific physical mechanisms associated with dissipation of energy in the movement of trains. Topics considered include car weight and aerodynamics, radial trucks, locomotive idling, power-to-weight ratio, track structure, stops, operating speed and variations in speed, and coasting strategies. Quantitative estimates of fuel-consumption impacts are presented for each factor in terms of the baseline train. Extension to other cases is facilitated by presentation of data and general formulas. One note worthy finding is that locomotive efficiency factors and train resistance account for only half of the fuel actually consumed; the major portion of the remainder appears to be dissipated in braking and, to a lesser extent, in overcoming curve resistance. (Author)

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/trr/1982/838/838-010.pdf
• Summary URL:
  • https://scholar.google.com/scholar_lookup?title=WHERE+DOES+THE+ENERGY+GO%3F+A+SIMPLIFIED+PERSPECTIVE+ON+FUEL+EFFICIENCY+IN+RAIL+FREIGHT+TRANSPORTATION&author=J.+Hopkins&publication_year=1982
• Availability:
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• Supplemental Notes:
  • Publication of this paper sponsored by Committee on Railroad Operations Management. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Hopkins, John B
• Conference:
  • 61st Annual Meeting of the Transportation Research Board
  • Location: Washington District of Columbia, United States
  • Date: 1982-1-18 to 1982-1-22
• Publication Date: 1982

Media Info

• Media Type: Print
• Features: References; Tables;
• Pagination: pp 55-61
• Monograph Title: Railroad Rail, Track, Regulation, Operations Management, and Commuter Issues
• Serial:
  • Transportation Research Record
  • Issue Number: 838
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Braking; Economic efficiency; Energy consumption; Engine idling; Freight transportation; Fuel consumption; Railroad transportation
• Uncontrolled Terms: Efficiency
• Old TRIS Terms: Idling
• Subject Areas: Economics; Energy; Freight Transportation; Highways; Planning and Forecasting; Railroads;

Filing Info

• Accession Number: 00362125
• Record Type: Publication
• ISBN: 0309033152
• Files: TRIS, TRB
• Created Date: Aug 30 1982 12:00AM