ZETA-TECH Associates has performed several analyses of the economics of alternative equipment types for a variety of rail services, including ocean container movement and the haulage of bulk commodities. These analyses have focused on changes in car load, train length, motive power assignment, route, and operating speed as possible sources of savings. Considered in each analysis are: ownership and maintenance cost of locomotives and cars, crew costs, fuel costs, track maintenance costs, derailment frequency and cost, and the cost of additional maintenance or early replacement of bridges.
Each analysis has involved a specific route with known profile and geometry, over which a number of consists are operated to determine running time and fuel consumption. The simulation tool used to determine these values is the Train Energy Model (TEM). TEM, which runs on a microcomputer, produces a detailed and accurate record of train speed, cumulative fuel consumption, locomotive throttle and dynamic brake notches, air brake applications in pounds, and drawbar force. This information -- along with additional inputs for car lease or ownership cost, per-mile maintenance cost, locomotive costs, crew wages and fringes, and certain maintenance of way cost data -- is then used in a costing algorithm to develop the direct variable cost of operations. These costs can be compared across simulation runs to produce the incremental costs or savings resulting from changes in operations or the use of different car types.
Several areas of cost reductions have been identified in ZETA-TECH's analyses. Heavier car loadings improve net-to-tare ratios (reducing fuel consumption per net ton) and reduce the number of cars required for a fixed-volume movement. Optimization of motive power assignments reduces locomotive ownership, maintenance costs, and fuel consumption. The benefits of new types of equipment may come in several areas: improved net-to-tare, reduced rolling and aerodynamic resistance, increased train length, and reduced intra-train forces. Increases in operating speeds, while increasing fuel consumption, can reduce equipment requirements by reducing load/empty cycle time.
Train simulation modeling has proved to be a flexible, accurate, and valuable tool in determining the optimal combination of car types, car loads, and operating practices for a range of railroad commodities.
BACK Copyright © 2000 by ZETA-TECH Associates, Inc.