The conflicting results from these studies are of limited usefulness in predicting total fuel consumption and fuel costs for individual grain shipments. This study measured fuel consumption in transporting grain from Iowa origins to Japan and Amsterdam by alternative routes and modes of transport and applied these data to construct equations for fuel consumption from Iowa origins to alternative final destinations. Barge fuel consumption data were taken from daily towboat logs for 11 tows on the Upper Mississippi River, and 16 southbound and 19 northbound tows on the Lower Mississippi River. The truck data were taken from three metered trips to Muscatine, Iowa. In addition, the company owning the metered truck provided records on 1983 fuel consumption for seven trucks with the same specifications as the metered truck but pulling flat trailers rather than hopper-bottom trailers.
Regression analyses related total fuel consumption to various vehicle and operating characteristics.
The results of the fuel tests and regression equations were used to predict fuel consumption from Iowa origins to Yokohama, Japan, and Amsterdam, Netherlands, via alternative routes and modes. Net ton-miles per gallon increased sharply with higher backhauls. The trucking company executives believe that the difference between the metered and the company record net ton-miles per gallon was largely due to driver performance. All trains returned empty. Average barge fuel consumption on the Mississippi River from Iowa to NOLA export grain elevators was 544.5 net ton-miles per gallon, with a 35 percent backhaul rate.