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  • Commuter Rail 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

 #1528170  by Ken W2KB
 
caduceus wrote: Fri Dec 13, 2019 8:50 pm
charlesriverbranch wrote: Fri Dec 13, 2019 5:19 pm But if a battery-powered car such as a Tesla is practical, then surely a battery-powered EMU is practical. Why build all that catenary infrastructure?
Moving a railcar requires just a bit more power than a passenger car. It would require MUCH more battery power, which comes with its own weight, which adds to the power necessary to move it.

It can also take hours to fully charge a Tesla, and you can only practically provide so much power to charge, so unless you are OK for a single rail car to make a couple runs and then need to charge for half a day, I don't think they're practical yet.

You could try swapping out battery packs, but that would be labor intensive. There were some tests with buses, but don't think much came of it.
Some twenty years or so ago, I recall reading an Electric Power Research Institute ("EPRI") article suggesting, albeit for lightrail vehicles, that extremely rapid charging of batteries could be accomplished at each station stop during passenger dwell time by using capacitive coupling. Most of the underneath of the railcar would have a large plate mounted and between the rails at stations a fixed plate would be mounted, forming a large capacitor thus requiring no labor to attach cables at stations or elsewhere. Such would eliminate the need for out of service charging, or at least require it at several hour intervals, perhaps before and after the rush hour periods.
 #1528188  by BandA
 
If you needed to physically swap batteries, you would use a robot / mechanical system, probably above or below. Such a system would have to be designed & tested.
 #1528225  by CLamb
 
Ken W2KB wrote: Sat Dec 14, 2019 3:51 pm Some twenty years or so ago, I recall reading an Electric Power Research Institute ("EPRI") article suggesting, albeit for lightrail vehicles, that extremely rapid charging of batteries could be accomplished at each station stop during passenger dwell time by using capacitive coupling. Most of the underneath of the railcar would have a large plate mounted and between the rails at stations a fixed plate would be mounted, forming a large capacitor thus requiring no labor to attach cables at stations or elsewhere. Such would eliminate the need for out of service charging, or at least require it at several hour intervals, perhaps before and after the rush hour periods.
A tram using supercapacitors instead of batteries with recharging from catenary at stations is in operation in China. The technology has also been proposed for use in Melbourne, Australia. https://cmte.ieee.org/futuredirections/ ... itor-tram/
 #1528228  by ExCon90
 
I thought they were also doing something like that on the streetcar system in Mannheim, Germany, but I don't remember where I read it.
 #1528261  by caduceus
 
Ken W2KB wrote: Sat Dec 14, 2019 3:51 pm Some twenty years or so ago, I recall reading an Electric Power Research Institute ("EPRI") article suggesting, albeit for lightrail vehicles, that extremely rapid charging of batteries could be accomplished at each station stop during passenger dwell time by using capacitive coupling. Most of the underneath of the railcar would have a large plate mounted and between the rails at stations a fixed plate would be mounted, forming a large capacitor thus requiring no labor to attach cables at stations or elsewhere. Such would eliminate the need for out of service charging, or at least require it at several hour intervals, perhaps before and after the rush hour periods.
I can see this for a system with stops relatively close together, but it's harder for longer runs. Capacitors can charge and discharge faster than batteries but can't hold the charge as long.
 #1528297  by CRail
 
Please stick to discussing the possible electrification of MBTA Commuter Rail lines. Battery propulsion is not a consideration at this time.
 #1528307  by Patrick Boylan
 
I disagree. If we're going to discuss possible electrification we should also be able to discuss possibly not electrifying. Battery should be a consideration. You may argue it's far fetched, but not that it isn't worth considering compared to how far fetched some of the prices could be for putting wires everywhere. With batteries charging off of the existing power lines they could start running electric service on the Providence line as soon as they bought the railcars. Unless of course I'm mistaken in what I've read that Providence has only a few short segments that aren't electrified already in places that commuter rail needs that Amtrak doesn't use.
 #1528394  by Type7trolley
 
Battery technology is currently not feasible for commuter railroad operations, nor will it be in the short term future. Furthermore, the MBTA is not in the business of developing and implementing entirely new modes of rail transportation.

This discussion is about as relevant to the Providence line (or any other) as the hyperloop.
 #1528423  by CRail
 
Patrick Boylan wrote: Mon Dec 16, 2019 8:18 am If we're going to discuss possible electrification we should also be able to discuss possibly not electrifying.
Which is not discussing electrification. Further commentary regarding non-existing technology will be removed.
 #1528457  by HenryAlan
 
BandA wrote: Sat Dec 14, 2019 12:55 am What "shocks" me about electrification, a (light rail) electrification project that took the MTA 1 year in 1958 ("D" branch) would take ten or more years today (GLX). Same order of magnitude problems seems to apply to time and costs of all of their projects.
Those are really substantially different projects. You can't compare the level of associated work. Plus, the actual construction of GLX isn't taking 10 years, much of that time was just politics and regulatory fights.
 #1529320  by BandA
 
rethcir wrote: Tue Dec 24, 2019 8:19 pmhttps://commonwealthmagazine.org/transp ... il-debate/
Finally, as to greenhouse gas reduction, we need to bear in mind that public transportation accounts for only a tiny fraction of statewide 24/7 traffic. While it is important downtown at rush hour, it accounts for less than 5 percent of all passenger-miles traveled. Even with an unprecedented doubling of transit ridership over the next couple of decades, 90 percent of travelers would still be burning fossil fuels on the roads. Our environmental priority has to be electrification of the private vehicle fleet. Fortunately, progress on that front is actually much cheaper than electrifying and expanding public transit. (See, for example, Carbon Free Boston, page 65, Figure 29.)
Senator Brownsberger makes some interesting points, calling for more parking! at T stations, saying the focus should be on fixing the choke-points for rush-hour commuters, not focusing on side issues, then he goes off & talks about some side issues.

That public transportation only has 5% market share is something to ponder.

We would be better off focusing on energy-efficiency and energy independence than greenhouse gas reduction which has to happen on a worldwide basis to be effective i.e. China and India. Energy efficiency & independence will make us stronger and save money and will make greenhouse gas goals easier later on. And fracking fuels will run out sooner than people think I bet and coal is still nasty dirty.
 #1529554  by charlesriverbranch
 
"Rush hour" is an outdated concept today, when people go to and from work at all sorts of hours, and in all sorts of directions. Route 128 is a zoo all day, not just from 8 to 9 AM and 5 to 6 PM. If you want to increase the percentage of trips made by rail, then rail has to go where people want to go, at the times they need to go. That's a tall order; it will require many billions of dollars. Want to go from Framingham to Lowell? The track was ripped up decades ago. Want to go from Quincy to Waltham? That track never existed.
 #1529582  by GP40MC1118
 
Darn right that the "rush hour" is an outdated concept. RT 128 is a a zoo all day. RT 24's upper half can be and the closer
you get to RT 128 it becomes (From Harrison Ave north).

After spending 35+ years commuting the RT140/24/128/X-Way or variants these later years it was significant factor in
choosing to retire.

Perhaps the most infuriating aspect of the "rush hour concept" was the HOV lane on the X-Way. To me, it was and is fiasco.
How can you take a lane away from inbound (north) traffic from Braintree by 2PM and declare victory! Most days it spills out
on to RT128! Doesn't anyone realize the commute northbound is just as heavy as the southbound? The lost time, gas burned,
the accidents from rearenders from stop & go, stop & go and land reductions really worth the so called gains?

D
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