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Trains are more efficient and less polluting than other transportation modes

citylab.com

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Re: Trains are more efficient and less polluting than other transportation modes

#291

Post by beatgammit »

I think one of the biggest issues that prevent making things better for passengers isn't necessarily the cost of building the infrastructure, but the acceptability of the status quo. The benefit to going with rail isn't dramatic enough to inspire urgency.

I really think it would be useful to completely eliminate most vehicles from city centers. Only mass transit would be allowed, and walking/cycling would be prioritized over that. People would go to one of the parking lots (which would also be train stations) outside the city and take mass transit to go to some common hub of the city. Since driving directly to your destination is no longer an option, catching a train closer to your house and improving mass transit automatically becomes important, and lower pollution and traffic within cities will improve many aspects of city living. Also, since roads would be much smaller, buildings can be built more densely, which improves walkability and livability of cities.

However, people are currently addicted to cars, so the conversation will likely never happen.

Re: Trains are more efficient and less polluting than other transportation modes

#292

Post by stickfigure »

Gibbon1 wrote: post #224
daurnimator wrote: post #206

Earlier quoted context omitted.

Why assume 4 hours with a recharge? I'm thinking closer to max 15 mins without a recharge. This would allow skipping electrification in some tunnels; in rail yards; on track segments shared with non-electrified trains; and anywhere that it's too hard to run electric lines.

Far as I can tell he's also off by a factor of 4. Tesla 85hw battery pack 1200 lbs. 3000 kw X 4 hours = 1200 kwh. 1200kwh/85kw*1200 = 170,000 lbs. A GE/NS Dash 8 weighs in at about 390,000lbs

210kwh for 3575 lbs comes from the tesla powepack specs:

https://www.tesla.com/powerpack

Furthermore, it makes zero sense to compare "3000kw x 4 hours" since diesel electric locomotives can run for N>>>4 hours.

Furthermore, you're comparing the weight of batteries alone compared to the weight of a whole locomotive.

Re: Trains are more efficient and less polluting than other transportation modes

#293

Post by anonymou2 »

narag wrote: post #142
jfoutz wrote: post #131

Earlier quoted context omitted.

I wonder if batteries, motor and third rail connections could be added to the flat cars that carry shipping containers. Skip the engine all together, and make trains fully dynamic. Probably not worth the cost. It would be kinda cool to see a long train split in half , front and back taking different routes.

It would be kinda cool to see a long train split in half , front and back taking different routes. That happens all the time here, in Spain. Some trains from Madrid to Andalusia travels to Seville with two locomotives, one in the front, another one in the rear. Then half the train goes on to Cádiz, half to Huelva. Oh, and it's sometimes very long, forty passengers cars + 2 locom. + several restaurant cars. I guess th…

Fast yes, cheap not at all. Conventional (not high speed) trains in Spain are cheap, but there are fewer and fewer of those. If you want to travel cheaply you mostly have to take a bus. Most trains here are now only for the rich.

Re: Trains are more efficient and less polluting than other transportation modes

#294

Post by anonymou2 »

narag wrote: post #143
CaliforniaKarl wrote: post #124

Earlier quoted context omitted.

Interestingly, trains today are technically diesel-electric, where a diesel engine is feeding a generator, which feeds traction motors on the axles. So putting in a battery would "just" mean swapping out the fuel tank, engine, and generator. Probably the biggest issue I could see is, the battery would have to be able to handle extremely high currents to get the consist moving. For example, https://en.wikipedia.org/wi…

That seems US specific. Of course it wouldn't make sense to use the batteries for that case, but maybe it would be cheaper for you than electrifying the network.

I know it sounds dangerous, but, haven't anyone thought of electrifying by just using the two rails as conductors, one rail per pole? So no need of third rail or catenary. I suppose the expense would be isolating all the axels! This is the method used by model railroads by the way.

Re: Trains are more efficient and less polluting than other transportation modes

#295

Post by ahoy »

apatheticonion wrote: post #132
bronco21016 wrote: post #62

I’ve visited Europe many times and I do like how the region is so easily accessible without a car, largely because of trains, but there are many more factors outside of just having trains. European cities are far more walkable and accessible without a car. For decades the US has just not been built up in this way so just dropping trains in doesn’t suddenly make them preferred and thus viable. The reason people drive…

Excuse my ignorance, but my foreigner layman's opinion is that your cities ain't broke, the US is the richest nation on Earth. Y'all just need to tax better and spend wiser.

The richest americans are very rich, yes. Most americans aren't rich.

Re: Trains are more efficient and less polluting than other transportation modes

#297

Post by Kaiyou »

ahoy wrote: post #295
apatheticonion wrote: post #132

Earlier quoted context omitted.

Excuse my ignorance, but my foreigner layman's opinion is that your cities ain't broke, the US is the richest nation on Earth. Y'all just need to tax better and spend wiser.

The richest americans are very rich, yes. Most americans aren't rich.

Which is better than the alternative of nobody being rich.

Re: Trains are more efficient and less polluting than other transportation modes

#298

Post by TylerE »

adrianN wrote: post #244
TylerE wrote: post #215

Earlier quoted context omitted.

No, because rail has fixed routes but everywhere in the road network is connected to everything else.

Everything on the rail network is also connected to everything else.

Hardly, especially not in the US where the track is not owned by a neutral party.

Re: Trains are more efficient and less polluting than other transportation modes

#299

Post by PebblesRox »

Gibbon1 wrote: post #133
jcranmer wrote: post #103

Earlier quoted context omitted.

> Most of the US freight rail system isn't electrified because the capital expenditures of doing so would be very large, and its return on investment in terms of direct monetary savings wouldn't materialize for many, many years. There's a decent amount of mainline freight rail that was electrified 100 years ago but has since been ripped out. It turns out that electrification has a lot of operational constraints that…

Thing that solves those issues are battery powered locomotives. This idea generally invites disbelief but when you run the numbers it works because the power to weight requirements drop as vehicles get larger. The result you can use overhead lines where safe, cheap and convenient and avoid them where they are not, like rail switching yards. https://www.railjournal.com/regions/north-america/bnsf-and-g...

Reminds me of the old fireless steam locomotives. Instead of boiling their own water to make steam, they had reservoirs that were filled with steam from an external boiler. Not practical for long-range travel, but good for switching yards and other local uses.

https://en.m.wikipedia.org/wiki/Fireless_locomotive

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