10 July 2016

The Capacity Problem

These days, Caltrain is breaking a ridership record nearly every month.  Rush hour trains are running with standing-room-only crush loads, measured by Caltrain's statistics as a percentage of seating capacity.  The most recent ridership counts (tallied during the low-ridership season in the first quarter of 2016) showed several trains running at 125% of seated capacity, even after the addition of a sixth car.  Capacity, or the lack of it, is becoming a problem and Caltrain will need to do more about it before 2020.

A montage of what a Caltrain EMU
by Stadler might look like,
based on a photo by Yevgeny Gromov
The recent award of electrification contracts, including an order for sixteen new six-car EMU trains from rail vehicle manufacturer Stadler, has brought this issue to the forefront.  Caltrain's Chief Operating Officer for Rail, Michelle Bouchard, had to concede in front of the Caltrain board of directors that the new EMUs would initially have a lower seat count than the diesel trains they will replace. The argument was that increased capacity could be achieved by increasing train frequency from 5 to 6 trains per peak hour per direction, and ultimately by lengthening the EMUs from 6 cars to 8 cars, something that can be done to an EMU without loss of performance or track capacity, unlike a diesel train.

Here are some thoughts about the capacity problem.

Capacity is measured in people, not seats.  Measuring passenger load factors as a percentage of seated capacity works well for airplanes, but doesn't quite do the trick for a transportation mode where passengers routinely stand.  The design of a train, including the number of seats, the interior layout, and accommodations for standees (handrails, poles, straps, etc.) has an enormous effect on the level of comfort experienced by passengers when the car operates at "125% seated capacity."  In rail vehicle A, filled with seats and with few places to stand, 125% feels uncomfortably crowded.  In rail vehicle B, with a lower seat count and large areas where passengers can comfortably stand, 125% of seated capacity feels just fine. A better metric of the true capacity of a rail vehicle is the number of seats plus some number of standees per unit of usable floor area (typically 4 standees per square meter); with such a metric, "100% capacity" feels like the same crowding regardless of train design.

Load factors over 100% seated capacity are desirable.  While this may be news to the person crushed between two sweaty people in the vestibule of a rush hour train, sizing the train fleet so that everyone can get a seat during the peak leads to a lot of empty seats running around the system or idling in yards during off-peak hours. This can be mitigated by changing the length of train consists (like BART), but unless trains are designed for this to begin with, it can't be done in daily practice.  Caltrain's new fleet of EMUs will not be easily reconfigurable unless two EMUs are coupled together; plans for this are not evident in the train configurations discussed in the EMU Request for Proposals (6 cars and 8 cars).  With fixed train consists, there is necessarily a sweet spot where a balance is achieved between two undesirable conditions: too many bums and not enough seats during the peak, and too many seats and not enough bums off-peak.  That sweet spot will mean peak load factors should very well be over 100% when measured as a fraction of seating capacity.

LIRR M-7 rail car with 5-abreast,
by Lexcie via Wikimedia Commons
Middle seats are seats, too.  The idea of 3+2 seating (five abreast) is usually batted away with a summary argument that passengers don't like middle seats, but it undeniably results in more seating capacity.  The question is, do passengers dislike middle seats more than they dislike standing? Commuter railroads on the East Coast seem to know the answer: the Long Island Rail Road M-7, the Metro North M-8, and the SEPTA Silverliner V, (to cite only the most modern examples) all feature 3+2 seating areas.  If providing seated capacity is so important, and if load factors are going to be measured as a percentage of seated capacity, then that middle seat is worth an easy 25% additional capacity.  The Caltrain EMU contract could be changed to require 3+2 seating; Stadler has already built a 3+2 bi-level EMU for a Russian client.

Fewer seats can actually increase passenger capacity.  If Caltrain stays with 2+2 seating and a lower seat count, the additional space for standees can provide greater passenger capacity if standees are properly accommodated.  The new EMUs should be configured with poles, handrails, grab handles or straps as necessary to allow standees to travel comfortably when no seats are available.  During the platform height transition period when Caltrain will be operating dual boarding heights (two sets of doors), the number of seats will temporarily drop after seats are removed from the high door boarding vestibules.  This may increase the load factor when measured as a percentage of seated capacity, but it will actually increase passenger capacity by opening up more room for standees.  Comfort may suffer, but only temporarily.

Caltrain should find a way to buy 8 car trains right away.  If some trains are already running at 125% seated capacity in 2016 during the winter low season, they are probably running at 150% seated capacity during the summer.  Seasonal load factor will go even higher if ridership continues to increase between now and 2020 when the new EMUs arrive.  By then, even with the entire Caltrain diesel fleet at six cars per train, the system will likely be bursting at the seams.  The step change in service quality thanks to the new EMU fleet will trigger another ridership increase.  Taking into consideration those three factors (high season peak, continued ridership escalation and better EMU service), it seems likely that six-car EMUs will be overcrowded from day one.  If Caltrain can scrape together another ~$150 million (another 7% of the total tab for modernization) to exercise an option on the Stadler contract, all EMUs can enter service in 2020 as 8-car trains.  Short platforms can be dealt with by prohibiting boarding and alighting from the front or rear cars at the few stations that cannot berth a 200-meter train.  An eight-car Stadler KISS with 2+2 seating will accommodate about 750 seated passengers and another 1000 standees.


  1. Adding a 5th seat (3+2) to every row of 4 seats (2+2) looks like a 25% increase in seating capacity to me.

    Of course, as Clem suggests, it's probably a net capacity reduction when considering standing space since seated passengers generally take up more space than standing ones.

    1. Right you are, I can't even do basic math.

  2. Speaking of there still being time to change the EMU contract ... I was disappointed to see that the EMU RFP "Section 15.2.2 LED Interior Lights" states "LEDs shall have a Correlated Color Temperature (CCT) range within 4,200 to 5,700 degrees Kelvin".

    This seems an unnecessarily cold and unpleasant shade of light. Pleasant and naturally "warm" light from traditional incandescent light bulbs is around 2,700 Kelvin. In my home, I found that 3,000 Kelvin is the sweet spot ... and that light in the 5,000 Kelvin range has a harsher industrial feel to it.

    Also, in a glaring omission, that interior lighting section of the RFP is completely silent on the CRI, or Color Rendering Index of the light -- which is simply a measure of how realistic colors appear in that light. Again, for reference, the CRI of a traditional ordinary incandescent warm white light bulb is 100. LEDs, however, come in a wide variety of CRIs. I have found you never want to go below 85 if you can help it, especially in kitchens and dining areas because you want the colors of your food to look right. Also in bathrooms and dressing areas, because you want to see colors correctly when dressing and grooming.

    So LEDs with high color temperatures (well over 3,000 Kelvin is progressively colder and blueish and/or "industrial" looking/feeling) and/or cheap high-output LEDs either do not specify their CRI and/or have CRIs less than 80 are something Caltrain should be sure to avoid. Why not have pleasing warm lighting which renders colors reasonably accurately and is easy on the eyes?

    With a little judicious shopping, you no longer have to pay any substantial premium for good quality LED light ... one just has to pay attention to specifications ... so why not tweak the spec now, before it's too late, and make sure the interior light looks and feels pleasing to the eye?

    1. How about CCT of BART train? Train in Europe prefer warm white while in Asia likes cool white. This preference may comes from eye color of each person.

    2. What is the CCT (degrees Kelvin) of BART train interior lighting (which I think is fluorescent)?

      I've never heard of light temperature (CCT) preferences being linked to eye-color. Please point me to a reference, if you have it.

      It's an easy experiment: buy a cool white LED (~5,000K or more) and a warm white LED (3,000K or less) bulb with a CRI of 85 or more and at Home Depot or Lowe's. To be fair, make sure they are both rated at about the same number of lumens (brightness). CRI is not always on the package ... so you can assume it's crappy if not listed. Good bulbs with CRI of 85 more more usually put it on the package. Then Put them into some sort of lamp/fixture in an otherwise dark room and see which one has more pleasant light ... for reading, cooking, eating, grooming or just sitting by. I predict it will be no contest ... the warmer 3000K high CRI light will always win by a longshot. Then return the one you don't like for a refund and buy more of the good ones and LEDify your house!

    3. It appears that BART has a variety of lighting standards, depending on the light source. For fluorescents, it is 78 CRI and 3500K (4100K for signage). CFLs are 2700K and 82 CRI. LED are 4000K and 70 CRI. Standard office lighting targets 3000K. I think 3000K to 4000K is appropriate for transit. High CRI (>90 CRI) is available in LEDs now, with only a small penalty to the efficacy (FYI, California Title 24 puts into effect a new set of requirements for light fixtures and lighting in buildings starting Jan 1, 2017. California Title 20 puts into effect a new set of requirements for lamps themselves starting Jan 1, 2018.).

  3. I rather suggest Caltrain to purchase 4~5 set's of 3-car or 4-car consist for midday, night and weekend. BART operate 3, 4 or 5-car consist to maintain 15/20 min frequency. Double decker 6-car consist will be over capacity during such period.
    Short consist still can be utilized during peak period such as San Francisco to Milbrae local train, SF to Redwood City Local train or San Jose to Palo Alto (or Menlo Park) local train.

    1. Isn't the whole point of EMUs that it's very easy to break a longer consist into two shorter consists? Those 3/4/5 car mid-day BART consists that you see are really broken up 6-10 car trains, that are then reconnected during peak hours.

    2. That was the big thing with EMU 100 years ago when subways in NYC were created. However, today's EMUs have moved into the direction of so called "Married" sets - sometimes you hear the term "married pair". What this allows you to do for example:
      1) Articulate married pairs for less wheels to maintain.
      2) Distribute transformer, engines and other equipment throughout the train to spread out the weight (important for #1).
      3) Provide wider and more open gangways between units which provides more room for passengers
      4) Add extra protection to cab cars which are now the only units that might be exposed to crashes.

      Around the world, you're seeing more an more "unit train" EMUs where a single train with through gangways allowing you to walk (or see) end to end. You do end up running empty trains at night, however, this is considered cheaper than expanding stations to allow longer trains at peak-time.

    3. One of the reasons for EMU is to not waste the length of one or two locomotives.

      Another reason for EMU is to distribute equipment, in order to keep axle load down (example multisystem Pendolino, such as ETR-610)

      One more reason for EMU is distributed drives, which is necessary for high acceleration and high speed trains.

      The ability to join EMUs for longer trains is a very useful side effect.

      Articulated EMUs make better use of the length of the train, but are not suitable for S-Bahn-style bi-levels. Single-level is not such an issue (as in FLIRT or German class 423, 430 etc.).

      In various places (among them VBZ), it has been shown that strengthening and shortening trains may or may not make economic sense, particularly if it means shortening just for a few hours (such as for the evening hours).

    4. @Max: why is articulation "not suitable" for bilevel cars? Works for TGV Duplex.

    5. An even more relevant example of a bilevel commuter EMU is the Bombardier Omneo / Regio2N in France. Open gangways and all.

    6. Hmmm, OMNEO looks really nice inside!

      I wonder why Caltrain didn't get more than one EMU bid. Did the RFP somehow say "don't even bother if you're not Stadler"?

    7. Oops, wrong OMNEO link!

      This brochure shows the nice OMNEO interior and side-view schematic layout.

    8. Articulation and bi-level normally means that the connection would be on the upper floor (as with the TGV 2N). That means that passengers have to get down a full flight of stairs to reach the lower level to exit/enter. This considerably increases dwelling time. (that's also why I mentioned S-Bahn style operation).

      The Omneo has the articulation with one single level at mid-height. This does, of course, work. One had to do some calculations whether the single level articulation (and the staircases around it) are better or worse than the conventional configuration. Articulation (with its Jacobs bogies) will create higher axle loads, which only can be compensated with shorter carbodies (which reduces the length of two levels. I think this is also the reason why the Omneo is not used for the Paris RER, but for regional and local services out in the province.

  4. Caltrain need more space for standing, like BART's next generation rolling stock.
    Seat turn around of Caltrain is faster then other US Commuter rail. Baby Bullet in traditional commute direction for example, there are bulk of ridership between San Jose to Palo Alto (20 min) and Sunnyvale/Mountain View to Palo Alto (8~10 min). There are also still significant amount of demand between south to Milbrae.
    With more frequent service, Caltrain will see more short distance trip.

    1. Caltrain competes best for medium distance trips like SF -> PA and SF -> MV which currently are about 40-50 mins long. It competes because people can sit and work on laptops giving people about 1.5 hours that they don't need to spend at the office or at night.

      If someone is going to stand on a train for 1.5 hours not working, then you might as well just drive.

      While this doesn't apply to everyone, but I'd guess that about 25% of people who ride caltrain would not be riding it if they couldn't get a seat say 90% of the time.

    2. As a regular rider of "Traditional commute" for 5 years, there are growing number of short distance trips within south of Palo Alto. As 101 and Central expressway become jammed, Caltrain can compete those auto trip if the destination is close to station (or shuttle provided).
      For this market, seating is not first priority but frequency is most important.
      Your mentioned "Reverse commute" usually more chance to have a seat, as train originated from SF. On the other hand, some traditional commute express are already standing room only from San Jose Diridon. Most of rider from Sunnyvale and Mountain view are difficult to find a seat.

  5. Since I was curious about capacity, here's sitting capacity for Caltrain Bombardier 6 car train today:
    3 cars (non-bike): 144 = 432
    3 cars (bike): 114 = 342
    Total: 774 seats
    Length: 6 cars * 25.91 meters + 1 locomotive * 21 meters = ~176.46 meters (578.937008 feet)

    OMNEO (extra long): ~670 (2+2 seating), 135 meters (442.913 feet)

    Someone check my math, but OMNEO seems to have a much higher density for same length even if you throw out the locomotive. Not sure how they do it given the single deck sections, but here ya go.

    1. The Bombardier OMNEO product page gives 4.8 seats/m in 2+2 configuration and 5.7 seats/m in 2+3. That is indeed very dense, although tricks can be played with seat pitch in these "brochure" figures, not unlike for commercial airliners.

      Your six-car bilevel example above comes out to 4.4 seats/m including the locomotive.

      The six-car Stadler KISS used on the Zurich S-Bahn (2+2) comes out to 3.6 seats/m. Those don't have large empty areas for bikes as Caltrain will.

      With dual-level boarding and expansive bike storage spaces (two entire lower levels), you lose ~150 seats and end up around 2.6 seats/m, which really sucks for a bilevel commuter train. 3+2 seating (which Caltrain should really really consider at this point) lifts that back to about 3.3 seats/m.

      Sheer seating capacity didn't figure strongly into the EMU RFP.

    2. (for comparison, BART's new fleet is at 2.5 seats/m)

    3. Nearly always having to stand for me (and for many) really kills what was so nice about all my years of commuting to work or school on Caltrain: kick back, relax or sleep, look out the window, read a paper, work on computer, have a snack or a beer, etc. None of this works so well standing.

      Caltrain really ought to go for 8-car EMUs and 3+2 seating right from the start. I suspect the 6-car EMUs with 2+2 seating at 2.6 seats/m will be standing room only pretty much right from the start. I believe Caltrain has built up a lot of latent demand out there ... and spiffy new quieter, faster, more comfortable trains will tap into that. I stopped riding the train because taking my bike on board was became just enough of a hassle to tip the scales toward "fuck it ... might as well drive". Lots of people like me would go back to (or begin) riding if the crowding for seats and bikes improved significantly.

    4. The Caltrain Bombardier BiLevel seating arrangement is inferior to Gallery Cars, in my opinion. Beside face-to-face seats, the pitch is also kneecap-touching tight.

      The amount of seats versus standing room should be determine by average distance of travel for the passengers. Less than 30 minutes, standing is okay. More than 30 minutes, seats are a must.

      BTW, is the 16-set ordered still represented 75% of what Caltrain needs? Didn't CHSRA offered to make up the 25% to bring down the unit price?

    5. @William: your "30-minute rule" is arbitrary and subjective. There are no actual or natural "cliffs" or "triggers" at X-minutes ... the effect of increased travel time, or standing time, or crowding is on a continuous scale because tolerance for these things varies from person to person ... people gets dissuaded or incented to (re)act at different points on a continuum.

    6. @Reality Check: while the "30-minute rule" isn't scientific, I think it is safe to say that as the travel time increases, people become less tolerant to standing, whether the threshold is 15-minute, 45-minutes, or not.

      Maybe I should clarify that I think the amount of seats should be proportional to the percentage of people who is traveling more than 30-minutes. Of course the percentage will vary through out the say, so an average number, say trains between 7 and 7, should be used.

    7. Another consideration here is that tolerance to standing is a function of time, not distance. With average train speeds increasing after electrification, more passengers will "stand" the discomfort for any given origin/destination pair.

  6. Clem:

    I understood from your previous postings, that trip times would not decrease. Rather the benefit of electrification was allowing better service (more stops) to many more stations. Which is it?


    1. Well, you're right that it's one or the other and you can't have it both ways. My vote would be for skipping Atherton to save everyone a couple of minutes.

    2. What's to stop splitting the time saving between making extra stop AND saving time.

      For example, if end-to-end locals get, say, 12 minutes faster, you could "have it both ways" by making a couple extra stops with 6 minutes of the savings, leaving the remaining 6 minutes for faster end-to-end trip times.

    3. Since I've started taking baby bullets from SF to MV in 2008, the train runs are taking longer and longer than ever. Take the 8:57 departure (with original 9:44 arrival in Mountain View).

      1) They added 2 mins when Palo Alto stop was included. By leaving SF at 8:57 instead of former 8:59am.
      2) They added 2 mins for the San Mateo bridge work, so arrival became 9:46
      3) Next the padded an extra 4 mins by leaving at 8:56 and arriving at 9:49.

      Since 2008, the same baby bullet travel time from SF got extended from 45 mins to 53 mins.... 8 extra mins total, although 6 really given 2 mins were needed for an extra stop in PA. In 8 years, we slowed the trains down by 6 mins...

      One other item of particular interest. Remember how timetable was slowed down by 2 mins due to the San Mateo bridge work? Well, looks like Caltrain wants to make that slowdown permanent (or at least that's how I read this)

      "On-time performance (OTP) was 90.5 percent, a 2.7 percent increase.
      These results are prior to the timetable change. The final bridge change
      out for the San Mateo bridges is happening on April 16, and the Quint
      Street Project should be done at the end of April. Once the slow orders
      for these bridge issues are lifted, OTP will be improved. This will also allow
      staff to see the true impacts of the timetable change."

      Found here (PDF page 7 / 129)

      Anyway, given the new EMU's, I'd like the schedule to be at least as fast as it was with the original Diesel Baby Bullets.

    4. I still see some construction activity on the right of way through San Mateo (fence work, painting, and landscaping), the trains continue to run at slower than normal speed through that area.

    5. Caltrain has been promising 45 minutes SF-SJ with EMUs. Highly optimistic if max speed stays at 79 mph.

    6. Looking more carefully today, there are now piles of ballast, stacks of old wood ties, and stacks of new concrete ties between Burlingame and San Mateo, the current slowdowns are for a track upgrade. And, of course, in areas with grade separations or four quadrant gates, Caltrain can petition for a max speed of 110 mph.

    7. Provided they can bring under control the dumpster fire that is CBOSS.

    8. Martin, your mentioned 8:56 express train uses Gallery car according to Caltrain website. With increasing ridership (and bicycle), dwell time is also increased. So, 2-door car should be used for this train but bike advocate requested Caltrain for capacity. So, Caltrain have to assign Galley car for this train.

  7. Funding for 8-car trains is in the VTA ballot measure for November, and for this and BART cars in the transpo tax that SF BOS is likely to vote to put on the ballot on Tuesday. San Mateo County is planning to focus November's tax on housing and look for transpo priorities in a different year.

    High Speed Rail suggested that they *might* contribute $$ for more capacity, especially since the 2-door platform compatibility configuration would result in Caltrain having to remove seats. HSR hasn't actually offered the $$ yet. At some point in the future they need a plan for whether and where they want platform compatibility, and that would be a good time to remind them of to pay for any loss of Caltrain capacity.

    1. Has anyone done any back of the napkin math on how much rebuilding of platforms will cost? Will the new Hillsdale be built with High Platforms from the beginning?

    2. Think about it. No station can be high-platform until all trains that need to serve it have high doors to match.

    3. Think outside the box! Stations can be built with high platforms prior to trains being available. It's possible to build the new Hillsdale with an extra 42" of ballast, to be removed at a later date. Cheap & easy.

    4. Well, this is actually a special case where we have station at new location that can be built high-platform from the onset. The downside is that it can't be used until high-platform equipment shows up, but maybe that's not such a bad thing here since the old station can stay in use.

      The new South SF station is getting moved as well, so that's another opportunity to build it high-platform from day 1.

      However, I'd like to hear more about how 4-tracks would run at these stations. Seems like we're getting an island here and there, but everything else is outside platforms.

    5. Touche! An extra 42" of ballast -- I like it. Bring on the high platforms!

      Level boarding can't come soon enough ... so I'd like to see Caltrain earnestly get going on it long before HSRA's high-platform trains show up on the Caltrain line.

    6. Metrolink unveils new locomotives that could help improve the region's air


      How do these locomotives compare to EMUs in providing better performance? Certainly much cheaper in capital costs than the Caltrain modernization program, which is now at about $2 billion even not counting CBOSS.

    7. Ignorant guess: they want the exhaust to be cleaner, which likely means slower power buildup. I'm betting the new engine won't do much better than an F40 on the standing-start mile, tho its greater power will show after the first mile.

      With five galleries on the level an F40 takes 100-105 seconds for the first mile-- somebody see how the Metrolink engines do.

    8. For those who may have missed, Clem replied to morris's duplicate question here: http://www.cahsrblog.com/2016/07/hyperloop-one-is-a-dumpster-fire/#comment-286650

    9. For the record, here is my reply from the other blog:

      The acceleration performance of a train is best measured in kW/ton (power to weight ratio)

      The new Metrolink locomotives weigh a porky 127 metric tons, and put out just 3100 kW at the wheels (and that’s being generous, not counting any power loss for air conditioning and lighting). With six Bombardier cars and 1000 passengers, the power-to-weight ratio comes out to 6.4 kW/ton, probably a bit less after accounting for “hotel power”.
      Caltrain’s new EMUs will weigh about 300 tons for a six-car set, and are rated at 4000 kW (continuous rating). With the same 1000 passenger load, the power-to-weight ratio is 11.1 kW/ton, or 73% higher than Metrolink’s super diesel. And that’s not all: EMUs can briefly exceed their continuous power rating, such as for accelerating out of a station. The Stadler KISS Caltrain just bought is rated at 6000 kW short term, giving a power-to-weight ratio of 16.7 kW/ton. That is 160% more acceleration than Metrolink’s super diesel, and on the same performance level as BART. If you’ve ever been on BART, you’ve surely felt how swiftly it accelerates.

      When you add more cars to the trains, the diesel gets even slower. The EMU does not.

      Short answer: diesels will always suck, and Caltrain made the right choice to go electric even at very high capital cost.

    10. With respect to the Hillsdale and South San Francisco stations, in talking to Caltrain staff, the plan is to have island platforms at both of these stations. In the future, third and fourth tracks can be added without affecting operations. The 3rd and 4th track at South San Francisco does require HSR to work out an agreement with Union Pacific whose SSF yard is adjacent to the station.

  8. ? Clem or others:

    What I really want to know is the practical performance differences between Caltrain's current fleet, a fleet powered by Metrolink's new locomotives which they are purchasing, or a fleet of EMUs as proposed by Caltrain.

    If we stick to a top speed of 79 MPH, and 1000 passenger load, what is the difference in time to accelerate to top speed for each of the three examples?

    I might add, is there any difference in time required to slow to a stop for each of the three possibilities?

    1. Not proven with numbers, but a (well-designed) EMU has better braking power than anything "diesel". With regenerative braking, it is possible to brake at the adhesion limit, and therefore achieving the maximum possible brake force with driven wheels. If more braking power is needed, it is possible to add magnet rail brakes to the bogies, which provide another bunch of kN…

      For the acceleration, I am sure Clem can provide more realistic numbers, but roughly, you could do some basic physics, and insert the acceleration of a KISS with 1.1 m/s^2. If I remember correctly, that acceleration can be maintained up to around 80 km/h. (that's about where the maximum power output is reached … some 6000 kW, just for traction). If you are lucky, you may get one third of that available in a diesel locomotive, which means that the diesel locomotive powered train starts "running out of steam" way earlier than the EMU.

      Another qualitative argument is that the EMU has at least 8 (if not more) driven axles, whereas the diesel-operated trains have 4; the higher weight of the diesel locomotive will provide relatively spoken a higher tractive force, but that is gobbled up by the higher mass to accelerate.

    2. Speed limit 79 mph, 1000 passenger load, 2.65 miles start-to-stop from Sunnyvale to Mountain View. The train performance characteristics (mass, power, weight on drivers, drag coefficients, etc.) go into my train performance calculator, which models track gradient, speed limits, aero drag and wheel friction, and adhesion-limited traction. It numerically integrates the 1-D differential equations of motion. Out comes a speed vs. distance graph.

      Caltrain F40 + 5 gallery: 3'51" at 41.4 mph average
      Metrolink F125 + 5 Bombardier: 3'43" at 42.8 mph average
      Stadler EMU (6 cars): 3'00" at 53.1 mph average

      As previously discussed it's all about power-to-weight ratio. The fancy new Metrolink locomotive saves 8 seconds per stop, on a good day when head-end power used for lighting and air conditioning is zero. The EMU saves 51 seconds per stop, more than six times better than Metrolink's new F125, and feeds a bunch of power back into the grid when slowing down.

      The huge performance boost arises because you go from 5.2 kW/ton (F40 diesel + 5 gallery + 1000 pax) to 16.4 kW/ton (Stadler KISS @ 6 MW). Like going from a pickup truck to a Tesla Model S.

    3. Could there be a few more seconds in favor of the EMU, considering the time it takes the train to move after the driver moved the throttle ahead? I would have to somehow confirm, but It may take maybe one or two seconds for the EMU to build up full torque. I am very sure that a diesel engine takes way longer. If that is indeed the case, we could say that the EMU gains a full minute per stop.

      What was the deceleration you used in your formula?

    4. Clem:

      Thanks so much for your performance results posted above.

      Do the manufacturers of the F125 and Stadler EMU publish such performance data? Have they actually done test runs on tracks to confirm what the mathematical calculations show?

      Do the BART train sets match this kind of performance?

      In any case it presents an impressive case in favor of electrification.

    5. Stadlerrail has a nice selection of data sheets available, which do show the relevant data. More conclusive information, such as a v/t diagrams does exist in publications, but may not be available online (the publication which most likely has very good articles (mostly written by he engineers involved in the product) is the SER, Schweizerische Eisenbahn Revue, which may be pretty difficult to be found in USAn libraries; they do, however publish the index, allowing you to try to find a copy).

      For serious interest, you may contact Stadler or Siemens and ask whether they do have technical publications, or where you can find them.

  9. Caltrain's locals stop 21 times and currently take 93 minutes. A F125 powered run would take 90 minutes, whereas a EMU powered run would take 75 minutes. Is it worth about $1.9 billion extra in capital spending to get this performance advantage?

    The Baby bullets currently take 64 minutes and would take 63 minutes using using F125 or 58 minutes using EMUs. Again, worth $1.9 billion?

    Caltrain has enough funding to replace the ageing Locos. Caltain certainly does not have enough funding to fund electrification, with over one-half of their proposed funding not secured.

    1. Certainly a legitimate question.

      However, the electrification is nevertheless worth it, if operation cost are taken into account as well. Unified rolling stock would allow a better (denser) operation. Conservatively, for a 30 minute interval schedule, one train can be saved. And it may be possible to do even more savings (or increased schedules) with a smart intermingling of using the trainsets as locals and express (it may actually be possible to provide 15 minute intervals with a minimum of additional trains).

      The 58 minutes for the expresses have a non-neglectable psychological effect … less than an hour … and that will bring over-proportionally more passengers.

    2. It is not just replacing the locomotives. The gallery cars are 30 years old. They are at their end of life and need to be replaced.

  10. From the minutes of July 7, 2016, JPB Meeting:


    “Michelle Bouchard, Chief Operating Officer, Rail, said there was a communication that referenced the number of seats in the EMU train sets at 550 seats. That number was used in the original RFP document to provide for an apples-to-apples performance comparison. It was the idea that there would be 550 people onboard and staff wanted competing bidders to provide performance under those circumstances. Staff will work with Stadler to maximize capacity for seats and standees. That capacity needs to be balanced with space requirements for Americans with Disabilities Act passengers, bathrooms, and the 8:1 bike:seat ratio. It is likely that the number of seats in a six-car EMU set will be less than today’s Bombardier or Gallery consist. The true benefit of this project comes from increasing frequency. Caltrain is going from five to six trains per peak hour, and it is anticipated to result in 10 percent greater capacity. The true capacity enhancement of this program lies in the fact that it allows Caltrain to pursue these increases in the implementation of a more efficient service pattern with a higher frequency. The EMU technology will allow Caltrain to get from end to end in 60 minutes and to serve many more stations. This will allow staff to tap into the unused capacity in the service plan today. She said when measuring the true benefit of this program people should look at total system capacity, not just the number of seats on a single consist. This project provides more capacity than there is today and in the future the JPB will be able to extend train lengths without degrading reliability or capacity.”
    A 10% increase in capacity? How does this work when many trains are currently operating at over 110% of capacity?

    Some trains are operating at over 140% to 150% capacity.

    New EMU sets with 550 seats and a single bathroom.

    Initially EMU trains were to have over 900 seats, as Roland has pointed out a number of times.

    Gallery (5-car) sets with 650 seats and at least 2 bathrooms per train.

    Bombardier (6-Car) sets with 762 seats and bathroom in each car.

    New EMU service is planned at running 6-car trains at six trains per hour in each direction, which is extremely shortsighted. They do however indicate that they have an option to increase to 8-cars/train, but there is no funding. Caltrain NEEDS more capacity NOW! And we have to wait at least five years before electrified service. Service disruption due to equipment failure is on the increase. Caltrain must consider longer and more frequent EMU trains and increasing current capacity now. Otherwise Caltrain is headed to a possible major meltdown…

    And for this privilege of riding overcrowded, infrequent Caltrain, we may have to pay higher fares...

    Click on: ITEM 12.Caltrain Fare Policy Study Overview…
    Presentation: http://www.caltrain.com/Assets/__Agendas+and+Minutes/JPB/Board+of+Directors/Presentations/2016/2016-08-04+Fare+Policy+Study.pdf

    Will the fare study be objective or be biased in favor of gouging the customer?

    There are some nutcases out there that suggest Caltrain fares are too low.

  11. "Do the BART train sets match this kind of performance?"

    Does any train in the world match BART's initial acceleration? Calculate how many seconds a BART train would take to cover, say, 210 feet (three carlengths) from a standing start, assuming 1-1/2 seconds to ramp up to 3 mph/sec, and then 3 mph/sec constant acceleration. Then go stand on the platform with your stopwatch and see if they live up to that. It'll be close.

    When BART was new, and running at 76 mph maximum, it could do a standing-start mile in maybe 62 seconds. That's with the momentary pause in acceleration as the tail end of the train clears the platform, and with no acceleration for the last 15+ seconds of the mile.

    1. JR E235s are just as fast

  12. Turns out 210 ft from a standing start takes 10.51 sec, using the above assumptions.

    1. @Jeff: never let a good crisis go to waste. Stadler bid $390M on the option for an additional 96 cars beyond the base contracted quantity of 96 cars, and I'm sure that after another check between the couch cushions the money will be found to make all EMUs 8 cars long at entry into service.

      @Tim, BART is indeed remarkable within the decrepit world of US rail transit. If you expand your scope worldwide, it's nothing very special.

    2. @Clem: I hope so… In some cases the busiest trains should be up to 10-cars, and they need to look beyond the six trains per hour limitation. Caltrain could be and should be carrying over 100,000, (Even 125,000) on a typical weekday. The current infrequent service plan just doesn’t cut it.

    3. Caltrain also need middle point turn around, so that they can put resource more efficiently more than 6 train/h. Traffic volume is highest between Sunnyvale to Palo Alto, and south of Milbrae.

    4. Congratulations!!! You just made the perfect case for Dumbarton Rail!!!!