Frequent Trains Off Peak

After electrification, Caltrain aspires to operate off-peak service at 2 or 3 trains per hour, instead of the current 1 train per hour. All-local service at 3 trains per hour works out to a fleet requirement of 12 trains in service, far less than needed for rush hour, but still racking up almost 300 train-miles per hour, or triple today's rate. That sort of service level will not be cheap to operate, unless two conditions are met to reduce operating and maintenance costs:

1) Operate Short Trains Off Peak

Shorter trains off-peak reduce maintenance costs by putting less wear and tear on the vehicles and track. The same revenue train-miles can be offered with fewer car-miles. The more off-peak service is provided, the greater the savings: at 3 trains per hour, operating 4-car EMUs instead of full-length 8-car EMUs off-peak results in a huge reduction of 25% fewer weekday car-miles.

Operating and vehicle maintenance
costs of US commuter rail, per car mile

Just how big are the savings? Typical commuter rail costs are available from the FTA's National Transit Database. The operating and vehicle maintenance costs for Caltrain and selected commuter rail operators are shown at right for the year 2015, normalized by the total number of car-miles operated. Some on this list (Metro North, LIRR, SEPTA and New Jersey Transit) operate sizable fleets of EMUs, but their maintenance costs are not significantly out-of-family with Caltrain; therefore, it's fair to assume that maintenance costs will not materially change after electrification. Since the FTA maintenance totals are not broken out by fixed and variable costs, we will conservatively assume that the variable cost (which scales directly with the number of car-miles operated) accounts for half of the vehicle maintenance cost. Squinting at the chart, let's estimate this variable cost at $2 per car-mile.

When you operate 12 hours of off-peak service at 300 train-miles per hour, the variable cost of vehicle maintenance racks up at 12 hours/day * 300 train-miles / hour * 8 cars/train * $2/car-mile = $58k/day. By reducing off-peak train length to 4 cars/train, the savings are half of this, or $29k/day. The savings from shorter trains accrue not just on weekdays but on weekends too, yielding annual savings of roughly $10 million.

Then you might want to factor in energy cost savings. Each car weighs about 60 tons loaded, and is accelerated to about 60 mph between two typical stops. The electricity consumed to accelerate is re-generated into the grid while braking for the next stop, with a round-trip efficiency likely in the neighborhood of 80%. That means overcoming the inertia of one car for one stop (neglecting drag) takes 4 MJ of electricity, or 1.2 kWh in more familiar units. At typical electricity rates of 12 cents/kWh, that's just $0.14/car/stop. Multiplying it up, $0.14/car/stop * 20 stops * 3 trains/hour/direction * 2 directions * 12 hours/day * 8 cars/train = $1600/day.  (Note that drag will significantly increase this figure, but can be neglected for this estimate because the drag of a 4-car train is similar to that of an 8-car train.) By reducing off-peak train length to 4 cars/train, the savings are $800/day. At less than $300k per year, this is just a rounding error compared to the vehicle maintenance, and can be ignored.

The Scharfenberg automatic coupler,
nicknamed "Schaku," linking up two
short EMUs (click for movie)

Offsetting these savings are the costs of making and breaking train formations several times per day, since the entire fleet needs to be available for morning and evening peak service with full length 8-car EMUs. Traditionally, this is a cumbersome operation that involves expensive and specialized labor, with ground crews stepping onto the tracks to connect pneumatic hoses and high-voltage cables. Caltrain is breaking with tradition by using a neat technological trick: the couplers on each end of the new EMUs are fully automatic Schakus, making mechanical, pneumatic and electrical connections in a matter of seconds at the touch of a button in the train cab. Barring any union rules relating to craft distinctions, making and breaking trains can be performed by train crews with zero additional labor cost.

2) Operate With One Conductor

Labor accounts for about two thirds of operating costs in typical commuter rail systems. Operating costs are strongly driven by train crew size. Minimum crew size is constrained by union rules that govern how many conductors must work on each train. Currently, the minimum crew size (dictated by Rule 11 of the agreement with the UTU) is 1 engineer, 1 conductor and 1 assistant conductor for trains up to seven cars, with a second assistant conductor required for an 8-car train or longer.

When contemplating a tripling of off-peak service, the cost of this minimum staffing level becomes prohibitive. Conductors are paid about $40/hour, and assistant conductors about $35/hour. Including benefits and other employee costs, the overall cost of these employees is easily double these figures. Additionally, conductors typically spend about half their shift time on board a revenue-producing train, so the necessary staffing levels are roughly double the number of trains in service. We saw earlier that it takes a fleet of 12 trains to operate off-peak service at 3 trains per hour per direction; staffing an assistant conductor on these trains would cost $70/hour/conductor * 1 conductor/train * 2 hours/(revenue hour) * 12 trains * 12 (revenue hours)/day = $20k/day. Again this is big money: the savings from removing the assistant conductor and going to one-conductor operation accrue not just on off-peak weekdays but on weekends too, yielding annual savings of roughly $7 million.

How do you sell this lower staffing level to the union?

1. EMUs can relieve conductors of some of their workload, after automation of many of their traditional roles (such as stop announcements, door and lift operation, or signal aspect acknowledgement). Fare verification (proof of payment) could even become a separate role carried out by roving fare inspectors.
2. Conductor staffing levels or pay rates can be renegotiated on the basis of actual ridership, instead of the number of train cars, since the new EMUs will have automatic passenger counters that collect detailed and accurate passenger ridership statistics.
3. Most importantly, the total amount of work for UTU-represented employees would increase, since one-conductor operation would enable a tripling of off-peak service, resulting in 1.5 times more labor hours even after cutting conductors staffing levels in half.

It isn't a stretch to envision Caltrain and the UTU re-negotiating the labor agreement to allow just one conductor on four-car off-peak trains; there is room for a compromise that can benefit everyone.

Future Fleet Implications

If you zoomed way, way, into Caltrain's
exterior paint scheme concepts,
the Schaku was plain to see

Caltrain's initial fleet of sixteen six-car EMUs (total 96 cars) will not have the ability to split into shorter formations, but once the option for 96 additional cars (total 192 cars) is exercised, and all trains are extended to their intended length of eight cars, the practice becomes not only possible, but necessary for providing frequent off-peak service.

The fleet needs to operate two service patterns:

1. peaks at 6 trains per hour with a fleet of 8-car EMUs
2. off-peak at 3 trains per hour with a fleet of 4-car EMUs

To support both service patterns using the planned fleet size of 192 cars (including a rather large spares ratio, to withstand regular grade crossing collisions), the optimal fleet configuration is probably something close to:

• 16 4-car EMUs for off-peak service, each with one bike car and one bathroom car, that can be coupled in pairs during peak hour service to form eight trains with eight cars each.
• 16 8-car EMUs for peak service, lengthened from the base order

This results in the following order breakdown for the 96 additional option cars:

• 32 passenger cars for CalMod 1.1
• 32 cab cars, for 4-car EMUs
• 16 bathroom cars (powered), for 4-car EMUs
• 16 bike cars (unpowered), for 4-car EMUs

This EMU fleet configuration enables 20-minute off-peak service frequency for at least $17 million/year cheaper operating and maintenance cost than would otherwise be achieved with a uniform fleet of all 8-car trains. That's a large amount, easily over 10% of Caltrain's current annual operating budget. Considering that Caltrain struggles every year to scrape together enough operating funds, a stronger way of stating it is that without 4-car EMUs and one-conductor train crews, Caltrain will simply not have the financial means to provide 20-minute off-peak service frequency.