Rail advocates often cite the superior environmental benefits as one of the reasons to justify construction of new and improved rail systems and services. However, some doubt has been cast against the oft-cited environmental efficiencies of rail passenger service. Opponents of projects such as the Midwest Regional Rail Initiative claim that certain factors, such as extra driving associated with grade crossing closures, and driving to and from stations, will erode the environmental benefits of rail service.

The purpose of this analysis is to examine the environmental efficiencies, based on fossil-fuel consumption, of rail passenger service, compared to automobiles, when factors such as grade crossing closures and trips to and from stations are factored in. This analysis will center itself around the proposed Midwest Regional Rail Service, especially the stretch between Chicago and the Twin Cities, which has been criticized lately by at least one "citizens" group.

PART ONE: TRAIN VS. CAR FUEL CONSUMPTION

Since the Midwest Regional Rail Initiative (MWRRI), if built, will use brand-new Diesel Multiple Unit (DMU) equipment for rail passenger service, the fuel consumption of a modern DMU, the IC3/Flexliner, will be used. A 3-car train using this equipment has a fuel efficiency of 2.5 Miles per gallon, or .4 gallons per mile.

For this analysis, automobile fuel efficiency will be 25 Miles per gallon or .04 Gallons per Mile.

To find the number of cars a train would have to supplant on a trip to save fuel, one must compare the two numbers. By dividing the train's fuel efficiency by that of the car, one can get the number of car's worth of fuel the train consumes:

This initial figure indicates that at least ten car's worth of passengers will have to be carried by the train for it to be more fuel efficient than cars. Yet this represents only part of the picture, as additional miles driven relating to grade crossing closures and travel to and from stations have not yet been factored in.

PART TWO: GRADE CROSSING CLOSURES

In their flyer Trains and the Environment, the Sun Prairie, Marshall, and Waterloo Coalition to Stop the Train gives an example where 100 cars a day would have to drive an additional mile to get to the nearest open grade crossing, from one that was closed.

Assuming there is one such crossing for every mile of track, this would represent 100 additional car miles a day for every route mile. Since, under MWRRI, there would be 20 trains a day on the route, this would be 5 additional car-miles per train mile.

At 25 Miles per Gallon, 5 additional car miles means that an additional .2 gallons of fuel would be consumed for every train mile. Add this to the train's previous fuel consumption rate and one gets the fuel consumption of the train when grade crossing closures are factored in:

The train's fuel consumption, when one factors in the additional driving associated with grade crossing closures, is now .6 Gallons per Mile, or 1.67 Miles per Gallon.

PART THREE: DRIVING TO AND FROM STATIONS

Grade crossing closures will not be the only source of increased driving associated with MWRRI; people will also drive to and from stations, just as they do to and from airports for air travel, and bus stations for bus travel.

According to the Sun Prairie, Marshall, and Waterloo Coalition to Stop the Train, in their flyer Trains and the Environment, the average car carries 1.67 passengers for all travel, and 1.86 for recreational travel. The number of MWRRI passengers traveling for recreational purposes is estimated at 78 percent. Thus, the average carload can be calculated by taking the weighted average of the two:

According to these figures, the average MWRRI-related carload carries 1.8182 passengers. The average MWRRI train is projected to carry 120 passengers each.

Assuming that the drive to or from the station is ten miles, the number of additional car miles associated with driving to or from the station can be derived through the following equations:

A total of 660 car miles would be associated with driving passengers to and from stations. Actually, this number would be lower, as not all passengers drive--some will take other forms of transportation to or from the station.

In order to factor this number into those already determined from earlier in this analysis, one will need to find the per train mile fuel consumption related to this driving. That can be found by dividing the 660 car miles that would be driven in association with a train trip by the approximately 450 train miles between Chicago and the Twin Cities.

The additional driving associated with getting passengers to and from stations averages 1.47 car miles per train mile. At 25 Miles per Gallon, this translates into .059 additional gallons of fuel being consumed per train mile. This, added to the train's total fuel consumption thus far, will yield the total fuel consumption of the train, after factoring in grade crossing closures and driving to and from stations.

The train will consume .659 Gallons per Mile of fuel, or approximately 1.51 miles per gallon.

PUTTING IT ALL TOGETHER

The train's total fuel efficiency of .659 Gallons per Mile, when contrasted with the fuel efficiency of a car, will yield the number of cars the train will have to take off the road in order to be more fuel efficient than those cars.

The train will need to take at least 16.475 carloads of passengers off the road in order to be more fuel efficient than automobile travel. Multiplied by the aforementioned average vehicle occupancy, one gets the minimum number of passengers which would have to be on board in order for the train to have a superior fuel efficiency to automobile travel.

The train will need to carry at least thirty passengers who would have otherwise driven in order to be more fuel efficient than the automobile.

CONCLUSION

Since the projected number of passengers to be carried by Midwest Regional Rail Initiative is 120 per train between Chicago and the Twin Cities, the required thirty number of passengers that must be carried in order to save fuel represents only 25 percent--one quarter--of the projected ridership! Needless to say, the train's fuel efficiency is still vastly superior to that of competing automobile travel even after factoring in the additional driving associated with grade crossing closures and travel to and from stations to drop off/pick up passengers.

One major item was left out of this analysis, however. One, the fact that some passengers may also switch from buses or air travel. If this switch were to result in fewer buses on the road or flights, large savings in fuel would be realized, reducing the "break-even" number of cars that must be taken off the road by a significant amount. Had this item been calculated, the economic advantage of the train would be significantly greater. In fact, if the above number of 30 would-be drivers riding the train is realized, the other 90 projected passengers could have switched from alternatives which consumed ZERO fuel and the train would STILL have a superior fuel efficiency.

One may have also taken a look at the additional driving generated figures mentioned earlier and found those miles to be significant, as the 660 miles in driving to and from stations, combined with the 5 car miles per train mile in grade crossing-generated driving, would result in approximately 2,910 car miles per train trip. While one may argue that such a figure is higher than the number of train miles traveled, it is nowhere near the amount of driving that would be done had the train not existed. Indeed, only eight carloads (15 passengers) worth of traffic would have to have otherwise driven in order for the car miles driven by would-be train riders to exceed the number of additional car miles generated by the train's existence--less than 13 percent of the number of passengers on the train!

Despite the claims of excessive generated driving caused by the MWRRI and improvements to rail passenger service, it is the conclusion of this analysis that the environmental benefits of the train are far superior to the alternative of driving, by a large margin.

Posted 1/13/01 by Aomhs