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Trains are more efficient and less polluting than other transportation modes

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

#191

Post by chungleong »

jcranmer wrote: post #182
chungleong wrote: post #160

Earlier quoted context omitted.

I normally live in Europe. At the moment I'm in Baltimore. The city's downtown area (around the inner harbor) is perfectly walkable. Nearby DC is also perfectly walkable, while driving is a nightmare. These two cities should be well connected by rail but they're not. People would drive to a parking lot beside a metro station and get into the city that way. Two cities can only be linked effectively by rail when there…

Washington-Baltimore is actually a very good connection by rail--you'll have a train at least once an hour--except that the station for Baltimore is in the wrong location. Baltimore Penn Station is located far to the north of the city, well outside the Inner Harbor that's going to be the center of tourism and visitors. What happened is that, historically, Baltimore-Washington was mainly served by the B&O, whose Balti…

Neither the metro or the lightrail reaches Penn. I don't know who designed the routes. Better connections between DC and BWI would better link the cities but they can't even maintain a bus line. Meanwhile, there's a billion dollar for the Silver line...

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

#192

Post by selimthegrim »

dejawu wrote: post #185
xvilka wrote: post #181

Today US, I believe, is at point of no return. I highly doubt we will see any considerable train system modernization, comparable to the Asian nations, EU, or, maybe, even Africa.

I bless the trains down in Africa

Ah a 30 day NUMTOT refugee

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

#193

Post by dorgo »

krferriter wrote: post #125
kikoreis wrote: post #86

Earlier quoted context omitted.

Interestingly, the cities are in part broke due to the infrastructure cost of maintaining sprawl — which only cars make possible.

Also gas taxes in the US are far lower than in much of Europe. Gas tax is 5.9x higher in Germany than in my state of NC, for example. Gas tax is what funds a lot of infrastructure development.

The purpose of gas tax is not bound to infrastructure developement. Germany may spend gas tax money for arbitary purposes.

https://www.energie-lexikon.info/energiesteuer.html

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

#194

Post by creato »

Robotbeat wrote: post #179
stickfigure wrote: post #177

Earlier quoted context omitted.

For a single small passenger car without any grade, maybe. From that video: 90kw/hr of battery. At peak power output of 180kw, you could run that for 30 minutes. The ubiquitous GE Dash-9 used in freight service here in the US generates >3000kw and can run all day. They're also usually run in multiples to pull long heavy trains. I wouldn't expect to see battery powered trains in the US anytime soon, except maybe short…

You, strangely, ignored the parent's point that you would just be using the batteries to reduce the amount of overhead wires you need, i.e. one would have opportunity to recharge several times a day. (It's not helpful to focus on the specifics of a proof of concept--unimportant in this discussion about what is feasible--versus the fundamental figures of merit of the technology... Unless one is prepared to make the ca…

Can you even transfer close to 3000 kW through any overhead wires or third rail systems? It seems like 25 kV is the max voltage overhead lines run at. That's 120 A that you need to transfer through a sliding conductor. That sounds problematic to me, but I don't really know for sure...?

And if you are proposing using batteries to reduce the amount of overhead wires you need, then the average power you need to transfer while connected to the wires increases, not decreases.

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

#195

Post by selimthegrim »

manigandham wrote: post #184
shereadsthenews wrote: post #12

Earlier quoted context omitted.

When you think of an American state with a growing population you can take the existing infrastructure as a given and plan for rail for your new capacity. Unless you are willing to say we're just not going to add transportation capacity for our new citizens, you face a choice of road, rail, or air. Rail is often a good choice. As for "far apart" this seems irrelevant. Ohio has a greater population density than does S…

It's not that simple or we would have it already. Rail is expensive to build and maintain, and stations even more so. The lack of freedom of a car means the train must stop where people want to go and this creates a lot of complexity in how routes are connected, the size and number of trains, service hours, total throughput, ticket prices, and most critically having effective last-mile transit so people can actually…

I took the train from Tucson to New Orleans last week. The train cars are 25 years old and in OK shape, the food was edible but overpriced (even with a vegan option), but all above the luggage racks there were streaks of dirt, where vacuuming had taken place but apparently not a complete job. The train arrived about 5 hours late and I felt compelled to apologize to the British couple seated next to me on behalf of the USA, after asking them if nationalized British Rail was this bad in the seventies.

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

#196

Post by selimthegrim »

Theodores wrote: post #150
perfmode wrote: post #9

Earlier quoted context omitted.

Never thought of that. Just replace the roads with rails. Remove redundant links in the highway network. Sounds like a job for a graph algorithm straight out of CS 261.

> Just replace the roads with rails. Elsewhere in this thread and in previous discussions there has been this notion that there isn't the room for rail, buying up the land would be too expensive and so on. For a lot of the US interstate there is this huge median between the two directions of the highway. In Europe you are lucky if the median is the width of a lane, in the US it can be a vast distance to the opposing…

I sat for two hours outside New Orleans last week watching freight trains cross the bridge ahead of us when we were just 10 unobstructed minutes from arrival. Right now passenger service to Chicago is suspended for the near future because the trestle (which is single track wooden but being replaced by a double-track concrete one of similar height (!)) is at risk of being overtopped by the flood relief spillway - there’s a rail replacement bus to Jackson (which itself had a fire enroute last month). Oh, and good luck finding out about this from Amtrak’s website - all it tells you is the train is cancelled and they’ve laid on a bus.

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

#197

Post by stickfigure »

Robotbeat wrote: post #179
stickfigure wrote: post #177

Earlier quoted context omitted.

For a single small passenger car without any grade, maybe. From that video: 90kw/hr of battery. At peak power output of 180kw, you could run that for 30 minutes. The ubiquitous GE Dash-9 used in freight service here in the US generates >3000kw and can run all day. They're also usually run in multiples to pull long heavy trains. I wouldn't expect to see battery powered trains in the US anytime soon, except maybe short…

You, strangely, ignored the parent's point that you would just be using the batteries to reduce the amount of overhead wires you need, i.e. one would have opportunity to recharge several times a day. (It's not helpful to focus on the specifics of a proof of concept--unimportant in this discussion about what is feasible--versus the fundamental figures of merit of the technology... Unless one is prepared to make the ca…

I don't think you've run the numbers.

A tesla powerpack is 50kw, 210kwh, and weighs 3500lbs.

A freight train that would normally be pulled by four 3,000kw diesel electric locomotives would need 240 powerpacks, and could run for four hours before needing a full recharge. Those powerpacks would weigh 420 tons - the equivalent of say, four fully loaded freight cars, and cost around $25M (plus whatever the locomotives cost).

The diesel-electric locomotives are a couple million each, ready-to-run.

Ah hah you say, you only need the batteries between catenaries! How fast do you think you can charge those batteries? If you can charge the same as the full discharge rate, then you need 50% of your track to be electrified, and you need it every four hours (assuming you're willing to risk full discharge cycles). Trains don't move very fast, so that's pretty closely spaced. And even worse, you now need electrical infrastructure with twice the capacity - you need to charge the battery and move the train.

Sure there's no technical reason you couldn't do this, but the economics are not looking good. Batteries are too weak.

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

#198

Post by stickfigure »

Robotbeat wrote: post #178
Gibbon1 wrote: post #133

Earlier quoted context omitted.

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...

It's crazy to me that people still scoff at the idea of batteries being a serious power source for things, but you're right, they do, even though there are 100MWh batteries deployed already with 1GWh batteries being approved and nearing deployment.

The experimental locomotive discussed in that link has 2400kwh of battery (probably significantly less in practice; you don't want full discharges). The diesel-electric locomotives they'll be working with generate about 3,000kw for as many hours as they have fuel in the tank.

Maybe (hopefully) batteries will get better, but I wouldn't go dumping my money into electric locomotive startups just yet.

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

#199

Post by lostmsu »

Veelox wrote: post #173
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.

Part of it is the US has a lot of land. Japan is one of the more extreme examples but they have ~8.7x people per unit of land. That makes a big difference on the kind of buildings and transportation you build.

But isn't a railroad much cheaper to build and maintain, than a highway of the same capacity?

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

#200

Post by flo123456 »

dorgo wrote: post #193
krferriter wrote: post #125

Earlier quoted context omitted.

Also gas taxes in the US are far lower than in much of Europe. Gas tax is 5.9x higher in Germany than in my state of NC, for example. Gas tax is what funds a lot of infrastructure development.

The purpose of gas tax is not bound to infrastructure developement. Germany may spend gas tax money for arbitary purposes. https://www.energie-lexikon.info/energiesteuer.html

Germany may spend anytax for arbitrary purposes though.
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