The Flaw in the Electrification Study Methodology

The GO electrification study team, in its own words, set out to be “objective, comprehensive, inclusive, and evidence-based.”[1] We have no reason to suggest they were not objective, and the work they present is “evidence-based.” However, the study was far from comprehensive, and did not test some of the most promising electrification scenarios.

The flaw in the methodology was the failure to recognize that new technology does not simply replace older technology; it can have more far-reaching effects. It usually makes little sense to buy a new technology, with new features, and then use it more or less exactly the same way as the old technology. GO did recognize that electric trains have faster acceleration, but the study ignored the potential to operate smaller, more frequent trains in the off-peak. It assumed that GO would run only one type of train on all routes. It also assumed that the existing fleet would be replaced all at once, and did not consider staged migration strategies that would require less capital investment up front.

Of course, it is impossible to be completely “comprehensive." It is not possible to test and evaluate thousands of scenarios for this type of project, even with computers. The accepted way to do this type of study is to identify promising technologies or combinations, usually based on the experience of other operators, and test them against operating scenarios that are optimized for each technology. Usually this is an iterative process. Rather than try to test thousands of scenarios, or even 24 as GO did, the study team could have defined a smaller number of potentially promising options, and then tried to make them as good as possible.

There are many suitable examples to draw on for such a study. Most commuter rail lines in Western Europe, Asia and Australia have been electrified over the past half century. In most cases, the railway company can show a good business case, with the capital cost of electrification offset by increased passenger revenues and reduced operating costs. However, simply electrifying an existing route, without any other changes to the operating plan (train configurations, service frequencies, and fares), rarely appears worthwhile.

Normally, electrification is justified because it allows faster and more frequent services, often using smaller trains for at least some services, at a cost that is offset by incremental revenues. Initial rolling stock capital costs are often kept down by using a mix of electric multiple units and electric locomotives, so existing cars can be retained to provide peak capacity. Sometimes, reductions in peak journey times are matched by fare increases.

The GO study ignored this experience. It could, more accurately, be described as a comprehensive study of the benefits of using electric locomotives to replace diesel locomotives.

The study therefore did not consider the following combination:

  • partial conversion to EMUs, with continued use of bi-level trains, with electric locomotives, as the “heavy lifters” for the morning and evening peaks;
  • operation of shorter trains at higher frequencies in off-peak hours, which is possible with EMUs at much lower cost than with the existing GO trains.

These changes would allow GO to take advantage of the capabilities of EMUs to operate a faster and more frequent service for non-peak passengers, where demand is more time-sensitive, while avoiding the capital cost of replacing the large fleet required to carry peak passengers.

GO’s Rolling Stock Technology review does note “It is believed that a 25 kV, European-derived multi-level EMU may be a feasible and commercially viable alternative for Metrolinx’s consideration.”[2] It seems some members of the study team recognized there might be some promising scenarios that had not been considered. But this idea was never pursued.

Multiple Units are trains formed of two or more cars, each with its own motor. They can be single- or double-deck, and either electric (EMUs) or diesel (DMUs). They are about 25% to 40% more expensive to purchase than ordinary locomotives plus unpowered rail cars, but they have many advantages for intensive urban rail services.

  • With power distributed to all the cars and all the wheels, EMUs and DMUs can accelerate and brake faster than unpowered cars pulled (or pushed) by a locomotive. On a typical GO route with 10 station stops, the total time saving can be 5 minutes or more. This may not sound like much, but a saving of 5 minutes, each way, or 10 minutes per day, can attract commuters to choose rail over driving.
  • With faster acceleration, fewer trains and fewer train crews are required to provide the same capacity. Faster trains are more productive, reducing unit operating costs.
  • Because power is distributed to each car, train lengths can be varied to match demand. GO’s existing service with 10-car trains propelled by diesel locomotives is efficient only if there are at least 1,000 passengers to fill each train. In rush hour, this is easy, but during the middle of the day, loads are typically 500 passengers per hour or fewer. With shorter EMUs, GO can operate more frequent trains for the same cost, attracting more passengers.

GO’s current business model of running high-capacity trains into Toronto in the morning peak, and home in the evening, is attractive for people who work normal, regular hours. But many people now work more flexible hours, coming in early or working late, or making trips during the middle of the day between offices or to visit clients. For these trips, GO’s service is slow and infrequent, and many workers choose to drive instead.

In Europe and in Australia, EMUs[3] are routinely used on suburban rail routes (see Figures 6 and 7). Most operators vary train lengths between the peak and off-peak, to maintain a high frequency while avoiding the high costs of running empty trains. Trains have only one driver, who usually also controls the doors. Most European commuter rail operators use EMUs because, taking all these factors into account, they are cheaper than diesel locomotive-hauled trains. Many also still operate some push-pull trains, propelled by locomotives, to provide higher peak capacity.

Figure 6: The regional rail “S-Bahn” system in Zurich, Switzerland, operates a mix of single- and double-decked EMUs, as well as single- and double-decked cars propelled by electric locomotives. Configured as 4-car trains, they can be coupled into 8-car sets at peak times.[4]

Figure 7: The rail system serving the greater Sydney region in Australia uses double-decked EMUs configured as 4- and 8-car sets, which can operate singly or coupled together.[5]

[2] GO Electrification Study, Appendix 4, Rolling Stock Technology Assessment, p. 16.
[3] Toronto’s subway cars are actually EMUs, although TTC does not vary the train length during the day. One reason is the high crew cost; TTC has a policy of operating with a two-person crew on every train; one drives, while the other closes the doors.