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Caltrain's electric fleet more efficient than expected

caltrain.com

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Re: Caltrain's electric fleet more efficient than expected

#211

Post by londons_explore »

grakker wrote: post #77
xnx wrote: post #20

Earlier quoted context omitted.

Do trains need batteries for regenerative braking, or is it sent right back on the same power lines?

The article says this version sends it back out on the same power lines, either used by other trains or pushed back into the grid. Seems like a perfect job for supercapacitors, although I have no idea about the feasibility of that solution. I imagine that batteries having huge input/output cycles like that wouldn't be healthy for them. Again, pulled from my imagination because I don't really know much about battery w…

If it were 1995, the optimal solution would have been NiMH batteries at the side of the track. They can do massive currents in and out, and a few tons of batteries would be enough to fully store the energy of a passenger train stopping from 60 mph to nil inside 30 secs.

NiMH could have been attached directly to the rails.

Today, lithium batteries win for Watts per dollar, and perhaps custom made packs could also be attached directly to the rails.

But a cheaper solution is probably bidirectional inverters, allowing the DC generated by the trains to be fed back into the 3 phase national grid.

Unfortunately, all trains in London today cannot regen into the grid - they can only regen into the rails and hope that some other train on the same rail is accelerating at the same time to use the energy. By my estimates, that only happens less than half the time.

Re: Caltrain's electric fleet more efficient than expected

#212

Post by DiogenesKynikos »

presentation wrote: post #185
blintz wrote: post #3

The electric Caltrain is so wonderful. It’s way quieter, the cars have nicer interiors, and it is running faster and more frequently than before. Between this, the new BART cars (also much quieter!), and Muni hitting a reliability & satisfaction records, there’s really a transit renaissance going on in the Bay Area. I really hope we can keep this going!

The train itself was quiet when I rode it from SF to Palo Alto but they were honking the horn almost nonstop… so much for peace and quiet.

That's because they still haven't eliminated the crossing points.

They need to turn every road or pedestrian crossing into an underpass or overpass, or eliminate it. They've started on this process, but it will take many years.

Re: Caltrain's electric fleet more efficient than expected

#213

Post by ZeroGravitas »

huijzer wrote: post #180
sunday_serif wrote: post #80

Earlier quoted context omitted.

Completely agree! The hard parts seems to be figuring out (1) how to cut red tape for only certain projects and (2) figuring out what red tape to keep. Chesterton's fence and all that.

I’m getting more and more convinced that this is a main problem all over the West. In Germany, a business owner called Marco Scheel is becoming more and more popular by being very outspoken about how bureaucracy is hindering him. His company is called Nordwolle by the way. They make clothing out of sheep wool. They spend a lot of effort finding the right type of wool so they don’t need chemicals to paint it. One majo…

I associate this attitude with criticism of Wikipedia and narcissism. I don't think it's a coincidence that it's often around editing things they are related to that this comes up.

I tried to do something and they stopped me. This is wrong, I should be able to do this and write my own story.

Which is a perfectly normal feeling. But if you end up saying that loudly in public without ever thinking, well what if the rule of "let this person do whatever they want" applied to people other than yourself, then that seems to indicate some lack of a wider view.

Re: Caltrain's electric fleet more efficient than expected

#214

Post by Symbiote »

DiogenesKynikos wrote: post #212
presentation wrote: post #185

Earlier quoted context omitted.

The train itself was quiet when I rode it from SF to Palo Alto but they were honking the horn almost nonstop… so much for peace and quiet.

That's because they still haven't eliminated the crossing points. They need to turn every road or pedestrian crossing into an underpass or overpass, or eliminate it. They've started on this process, but it will take many years.

Trains don't honk in much of Europe when approaching a gated crossing.

The lights and barriers are assumed to be sufficient. Within cities, there may well be CCTV cameras (pointing only at the crossing) so the signal controllers can check the crossing is clear.

More video than you could possibly want:

https://m.youtube.com/watch?v=hidjpkqJ0-Y

(I think the honk in the first one is the train driver recognizing the person filming? It's far too late to be for safety.)

Re: Caltrain's electric fleet more efficient than expected

#215

Post by Nemo_bis »

lmm wrote: post #43
readdit wrote: post #4

Earlier quoted context omitted.

I feel this is positive news moving in a positive direction. Do you suggest not doing anything to improve the situation? We can’t go back in time. But we can help ourselves in the future.

One way to help yourselves in the future would be to learn the meta-lesson that actually things that work in other countries mostly work the same way in the US too.

Yes this whole thread is so depressing. Most commenters here are talking as if electric trains were an oddity. It's like listening to people questioning the benefit of running water over the old school walk to the well.

Re: Caltrain's electric fleet more efficient than expected

#216

Post by stuaxo »

defrost wrote: post #51
ssuds wrote: post #45

Earlier quoted context omitted.

Speaking of BART, this story is priceless: https://www.sfgate.com/bayarea/article/bart-seat-slasher-hur... The firm that reupholstered damaged BART seats in the ‘80s paid people to slash them so they’d get more business.

I love these kinds of true snippets of general security history: It was estimated that "possibly 85 percent of the more than 7,000 BART train cushions damaged since August 1979" was the work of this company, the Examiner reported at the time. All said and done, BART had paid the company $115,000 for the repairs, a total of about $339,128 in today's money. Always follow the money.

The profit motive always incentiveses this sort of innovation and efficiency when it comes to making more profit.

Re: Caltrain's electric fleet more efficient than expected

#217

Post by chgs »

jlmorton wrote: post #171
saagarjha wrote: post #104

Earlier quoted context omitted.

Wait, BART director is an elected position? Why don't I get to vote on it? (Also, while I am biased towards Caltrain, the new trains beat traffic on 101/280 San Francisco↔San Jose during rush hour).

It shouldn't be, though. There is way too much democracy in California localities. There should be no elected school board, transit districts, utility boards, assessors, sheriff, and so much more. No one is properly informed about candidates for these positions. For that matter, the Board of Supervisors should have no power other than oversight and impeachment. The Mayor should basically be a local dictator, with the…

Americans seem to have a view that if you get a part of an unengaged electorate to mark an x in a box every few years that’s democracy, and more is thus better.

Instead it removes accountability from public servants who can simply hide behind the “elected” excuse.

Re: Caltrain's electric fleet more efficient than expected

#218

Post by acchow »

Animats wrote: post #136

That's good to hear. Especially since the electric trains accelerate so much faster than the Diesel ones did. Have you been next to one at takeoff? They're going about 40MPH before the train has traveled its own length. Probably limited more by standing passengers than power. Most of the energy used accelerating is recovered at the next stop, so the fast acceleration does not consume much energy.

> so the fast acceleration does not consume much energy

Also, acceleration has no effect on the energy if you’re trying to hit the same target speed (unless there is friction, in which case you’d use less energy with higher acceleration)

Re: Caltrain's electric fleet more efficient than expected

#219

Post by djaychela »

justinzollars wrote: post #47

> With the agency expecting approximately $6 million annually in energy credits from the California Air Resources Board’s Low Carbon Fuel Standard Program the first year of electric service will have lower fuel costs than the previous diesel service Thats the key. Without the subsidy its more expensive and less efficient than carbon based fuel. In the long run we are worse off, because the subsidy can't last forever.

>In the long run we are worse off, because the subsidy can't last forever.

You're making the classic error here of not factoring the externalities involved - the pollution and other issues from fossil fuels. If they were actually being paid for then electricity would be much cheaper. Fossil fuels get a defacto subsidy by being able to pollute the environment without any cost.

Re: Caltrain's electric fleet more efficient than expected

#220

Post by tialaramex »

usr1106 wrote: post #207
thirtyseven wrote: post #195

Earlier quoted context omitted.

Being a first mover didn't prevent them from adopting standard gauge which already had existed for 100 years.

It has been said the broader gauge was chosen at the time to make trains able to run safely over Golden Gate Bridge with strong side winds. My physics is not good enough to calculate whether that argument makes sense. And I have no idea how realistic that route ever was. I don't think the gauge is a major problem. Train orders are always a custom project, few urban networks use exactly the same standards. Railroad ma…

In particular the track gauge is a long way from being the only consideration. Structure gauge and Loading gauge are also crucial. When I first moved here despite this being an important port city a Victorian arch bridge carrying road traffic over the railway meant every single freight train carrying containers from the port to the rest of the country needed to either go on a circuitous route or use special low wagons with reduced capacity, which hold a container below axle height so as to fit under that bridge.

In that case blocking the road and dropping in a new road bridge was affordable given the economic value but generally you put up with what you've got.

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