• MBTA Bus Fleet Electrification

  • Discussion relating to commuter rail, light rail, and subway operations of the MBTA.
Discussion relating to commuter rail, light rail, and subway operations of the MBTA.

Moderators: sery2831, CRail

  by TurningOfTheWheel
Given that rubber-tired vehicle discussion is welcome here on RR.net, I think it's worthwhile to have a topic regarding the ongoing bus fleet electrification at the T. The goal is to have a 100% battery-electric bus fleet at some point in the next two decades. The following presentation offers a look at some of the projects and priorities the T recently outlined to the FMCB: https://cdn.mbta.com/sites/default/file ... update.pdf

One item of note is that the T is planning on a full conversion to BEBs, including the trolleybuses in Cambridge and the Transitway. No new trolleybus routes are in the plans.

Key project dates as of April 2021:
2022: retirement of SL transitway dual-modes, replacement with hybrids
2022-24: retirement of NFI diesels, replacement with hybrids
2023-24: retirement of Cambridge trolleybuses, replacement with BEBs
2026: retirement of current 60-foot fleet, replacement with BEBs
2028-29: retirement of CNG fleet, replacement with BEBs
  by R36 Combine Coach
Noticing a trend toward battery power and away from trackless trolley buses. SEPTA is also planning to replace
the New Flyer fleet with battery power vehicles. That would leave Dayton, San Francisco, Seattle and Vancouver.
  by Arborwayfan
Going to battery-powered buses seems like a really optimistic assumption about battery life and long-term battery prices. There's only so much lithium, and the batteries can't last as long as the various electric infrastructure. I can't see taking down existing trolley wire and switching to battery. Maybe switching from diesel to battery. Any EE or ChemE types know more than I do and want to share.
  by TurningOfTheWheel
I agree that the race to take down the trolleybus wires seems incredibly short-sighted. I'm no hydrogen fuel cell evangelist, but even that would be a more certain long-term bet than a fleet of 1,400+ battery buses. I would argue that, considering the environmental impacts (my field of study) and infrastructural concerns (my future career), expanding the trolleybus network is a more prudent long-term play. They do seem pretty serious about it, however, having already run battery buses in the Transitway.
  by octr202
The MBTA (and SEPTA) are being really shortsighted in their quest to eliminate trolley wire. Dayton, the west coast cities, and European operators are moving towards in-motion charging trolleybuses, which leverage the existing overhead system. These aren't "pie-in-the-sky" options, they're out there now. Instead, the T is proposing to spend millions converting North Cambridge to service BEBs. With IMC, you could likely convert several additional Harvard Square area routes to electric operation without having to depend on full BEB buses, which still have serious limitations in terms of range and coping with extreme heat/cold.

The "enhanced hybrid" buses they're talking about for the Silver Line are equally a step backwards - they're designed to run on diesel in East Boston and Chelsea, in order to run in battery-only mode in the tunnel - in effect transferring the emissions to those neighborhoods. They're also slated to just about the most expensive city transit buses ever built at (IIRC) close to $2 million per bus.
  by octr202
Forgot to add that TransitMatters is already working on pushing for a more practical approach to bus electrification at the T, pushing for a strategy which encourages IMC trolleybus use for corridors with high density of bus traffic and/or existing overhead infrastructure. They're also advocating for a more cautious and varied approach than putting all of the T's eggs in the pure BEB basket and hoping the technology matures fast enough.


Also worth noting that in many instances so far, BEB use has required a larger fleet than the conventional bus fleet it replaces, due to the time needed to charge buses at the garage, and limitations on how long a vehicle can be on the road before it needs a long charge. Something to consider when the T is already constrained for garage space - widespread BEB conversion might require even more garage space.
  by BandA
That document is so full of jargon and abreviations. Why are trackless-trolleys now being called "trolleybus"? Trackless-trolleys are awesome except when the trolley-poles fall off occasionally & have to be repositioned.
Neither Fellsway nor Lynn can be modernized on site for even today’s fleet size
Apparently "modern" facilities take up more space than "obsolete" facilities.
Albany’s central location means it will play a critical role in the bus network as other facilities are modernized in place; ongoing investments reflect its continued importance moving forward

Given Albany’s existing route assignments, a new facility could be as well or better located a few miles to the west
Is Albany Garage's central location critical or should it be relocated to the west? It can't be both strategically & poorly located at the same time. And good luck locating a facility a "few miles to the west". Maybe Harvard will sell the MBTA part of Beacon Park for a few $B. As the most affected of the garages by the pandemic they don't know if/how traffic will rebound...
  by octr202
Globally the term trolleybus is more widely used. Trackless trolley seems to be predominantly northeast US - growing up in Philly they were always called tracklesses. West coast seems to prefer trolleybus. ETB (electric trolleybus) is the standard industry shorthand, with IMC-ETB being the new generation with in-motion charging.

Upgrading some of the garages will be difficult simply due to the number of buses assigned. The T's bus system is operating pretty much at full capacity from a garage standpoint. You close a portion of a facility for construction, where do those buses operate from in the interim? And then some are just on such tight footprints that it's just not cost-effective to rebuild them where they are. Better to find new sites where a larger facility with room from growth can be located.

Much of Albany St's routes operate to the near western suburbs - it was intended as a garage for the express/commuter buses, but also runs routes in Brighton, Watertown, Newton, etc.
  by Disney Guy
... called tracklesses ...
Milwaukee (and maybe some other cities) first called them "trackless trolley cars" since the "regular" streetcars that predated the tracklesses were called trolley cars.

Incidentally Milwaukee later simplified their lingo to "cars" for streetcars, "trolleys" for the tracklesses, and "buses" for the you know what which Milwaukee originally termed "auxiliary buses" and which originally ran as feeders to the trackless lines.

I think it was J.G. Brill which first used the term "trolley coach" but earlier, Brill called them "railless cars."

Some care will have to be used when developing in-motion charging systems. If a bus is to be charged at the rate of one hour of charge for two hours of off-wire operation, the bus will pull three times the power from the wires as a non-battery trolley bus would draw. For bringing a large number of buses , say from Belmont and Arlington Heights and more, into Harvard Square, the overhead wire system could need a lot more juice.
  by TurningOfTheWheel
I assume with regen braking it won't be quite three times the power, but point well taken there ;)

The more I think about the logistics of an all-battery bus fleet, the less confident I am that any transit authority can competently pull it off. The infrastructure required and environmental impact of all those batteries would be insane.
  by BandA
There's a substantial loss just charging the battery I think. Much more than the loss distributing the power through a wire.
  by rethcir
There are a lot of variables affecting the efficiency of charging a battery. Tesla charging is 80-96% efficient depending on the equipment.

I don't know what the operational overhead is on the trolley lines. I frequent Mt. Auburn St and don't see stranded trolleybusses hardly ever.

I would also note that the Mt. Auburn route is a pretty nice way to get around. Frequent service. They really could use dedicated bus lanes however. The WaterTownies kind of pushed back on that though i think.
  by Arborwayfan
Glad I'm not the only one who sees advantages in simple technology that lasts a really long time. Maybe batteries for the once-an-hour routes, but the five- and ten-minute headways seem to justify the infrastructure, especially when it's already there. Yes, sometimes buses dewire, especially when the slip in the snow at that one intersection on Mt. Auburn St. And yes, they can't easily detour if the whole street is blocked; but one solution to that would be special towing points and a couple of compatible tow trucks... :-)

Trolebuses de Valparaiso SA runs buses more than 50 years old in Chile.
  by west point
Battery powered anything has some apparent problem. The denser the battery cells the hotter they can get. then you have fires. A partial short has caused battery fires in computers, cell phones, power tools, airplane batterys, airplane cargo with at least 3 crashes . And the beat goes on.

Now we hear that about 25% of electric car owners go back to gas. Why? not revealed yet.
Hint" Do not charge any Li ION battery when hot unless your charger has overheat protection.
  by octr202
A couple notes to the above:

1. Mt. Auburn St is due for a total reconstruction, and to the best of my knowledge Watertown has always been supportive of keeping the wires, and plans to design in more bus priority features in the reconstruction.There's not too many places a full bus lane is needed on the 71/73, but intersection priority is key. Watertown has also worked closely with Cambridge on the bus priority lanes near the Cemetery, and has also installed a couple queue-jump lanes as trials along the inbound side of the street (allows buses to use the right turn lane to go straight, allowing them to pull up to the front of the traffic queue at an intersection). I'd have to go back to look if they also did transit priority signals, but I don't think so. You can see an example of that at Mt Auburn St & Coolidge Ave in Cambridge.

(Contrast with Belmont, which did little other than stop consolidation on the 73 Belmont St/Trapelo Road construction a few years back.)

Also - the Mt Auburn reconstruction does not include Watertown Square - a big source of traffic delays. That I believe will be a separate project.

2. Avoiding becoming stranded in a bad spot is just one of the many advantages of IMC ETBs...even the early versions that only have short-range batteries. Need to detour around a blockage? Just do it on battery. Poles dewire in the middle of the Aberdeen Ave intersection? Poles automatically retract and hook (a feature already on the Neoplans), drive on to the next stop and put them back up there. Or even keep going to the terminal if the vehicle has sufficient charge. There's a lot of flexibility.

3. The T likes to throw around maintenance cost savings to justify this conversion, but there's some research being done by advocates that shows the costs of even a full re-install (such as was done on Belmont/Trapelo) is remarkably low, because we're not talking about 100% new infrastructure. That's the beauty of expanding the networks with IMC ETBs out of Harvard Square and the Silver Line tunnel - the hard part is already in place, and just needs to be maintained.