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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

#211

Post by fzeroracer »

LaGrange wrote: post #152
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…

> European cities are far more walkable and accessible without a car. A really weird experience I had while visiting CA (SSF specifically) was seeing a fast food place - I think it was Wendy's? - that wasn't reachable by foot in any clear way. Similarly there wasn't any obvious sidewalks or bike lanes on the highway between Brisbane and SSF, and while that _is_ as 2km walk, I'd still expect it to be _possible_. I mea…

I currently live in Austin and the general infrastructure here is atrocious. There are many places that are inaccessible as you've mentioned by walking and biking in America is incredibly dangerous.

Most cities in the US are simply not equipped to deal with any sort of large population growth due to the incredibly bad infrastructure we have in place and zero motivation to improve it.

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

#212

Post by twic »

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…

I don't know this area at all, but apparently there is a commuter rail service (as mentioned) from Camden Yards, which still has a station, to Washington. But it takes an hour and a quarter, where the Amtrak train takes 45 minutes.

This is depressingly familiar situation in the UK too (not sure about the rest of Europe). Usually, it's not politics that prevent more useful connections being made, but a lack of investment to do the necessary small bits of engineering.

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

#213

Post by natch »

baroffoos wrote: post #156
natch wrote: post #127

For now, yes. Electric vehicles backed by sustainable power, when we reach that distant but ever-nearing goal, will be pretty good. Not as fast as flying but maybe we’ll get practical commercial passenger electric aircraft at some point. On the delivery of goods side of things, the Tesla Semi should also be a game changer. Efficient and door to door. For trains, I’d love to see how much could be done with, say, a ded…

Electric cars are still not good enough because they weigh so much more per passenger than electric trains

Good point. Wish we had more electric trains in the US. And you still need a solution for the last few miles after arriving at the train station.

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

#214

Post by sgift »

stickfigure wrote: post #198
Robotbeat wrote: post #178

Earlier quoted context omitted.

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.

You don't need power for the whole trip. If most of it can be electrified with wire and you only have small patches which cannot (like the tunnel mentioned) current battery technology is up to the task. We will introduce that here in the near future for a new tram line going through a park (where we don't want overhead wires).

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

#215

Post by TylerE »

lostmsu wrote: post #199
Veelox wrote: post #173

Earlier quoted context omitted.

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?

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

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

#216

Post by stickfigure »

daurnimator wrote: post #206
stickfigure wrote: post #197

Earlier quoted context omitted.

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 co…

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.

Sure... but now you're only saving a small percentage of the total electrification cost, and paying for increased cost, complexity, and maintenance of locomotives. It's not an obvious win.

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

#217

Post by TylerE »

creato wrote: post #194
Robotbeat wrote: post #179

Earlier quoted context omitted.

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…

The most powerful locomotives are all electric. Powerful freight locos have power outputs of over 13000kw

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

#218

Post by TylerE »

narag wrote: post #147
kposehn wrote: post #116

Earlier quoted context omitted.

Power density is the main issue. There are some experiments with batteries, for sure, but you can't really create the same density of stored energy as diesel that would actually fit on a frame and can be recharged in some semblance of a normal time . IIRC it was bandied back and forth but you'd only get a few hours of peak load, vs a diesel which can run at peak power for days before running out of fuel.

IIRC it was bandied back and forth but you'd only get a few hours of peak load, vs a diesel which can run at peak power for days before running out of fuel. The USA have very long distances, unusual for other countries. A few hours are more than enough for short travels. Anyway, recharge times are irrelevant if you could change them easily.

No they’re not. Availability. A locomotive that’s charging isn’t pulling a train. They’re like airliners, they don’t sit around idle for long periods. Too much capital tied up in them.

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

#219

Post by mikekchar »

fyfy18 wrote: post #207
masklinn wrote: post #203

Earlier quoted context omitted.

> Washington-Baltimore is actually a very good connection by rail--you'll have a train at least once an hour That's really not a lot, especially between major cities.

For comparison, in the UK there are around 8 trains per hour during peak times between London and Cambridge (around twice the distance of DC-Baltimore). I'd imagine there are cities that have even more per hour in central Europe.

Although according to Google Washington DC has 700,000 people and Baltimore 600,000. Probably a more realistic comparison would be Bristol and Southampton/Portsmouth where there is realistically 1 train an hour (technically 2, but the second one has a change and runs 8 minutes after the first one).

Comparing trains from London is not really fair because virtually every train in the south ends up in London eventually. Somewhat tragically, I once tried to take a train from Watford to visit Hatfield House, some 14 miles away. I think it took me 3 hours getting in and out of London :-)

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

#220

Post by bartimus »

What I found interesting is that in the US the government had a huge role with developing the rail network while in the UK it was entirely done by the private sector.

I'm from the Netherlands where the rail network started out as a state owned company. It then got privatized by splitting ownership horizontally. Meaning one company owns the rail network while other companies provide train services on top of that network. This in contrast to Japan where ownership is split vertically. Multiple companies owning sections of the network including the train services. It amazes me that the Japanese model is able to achieve their famous punctuality. To see multiple privately owned companies working together in perfect harmony. In the Netherlands the railway system still needs state funding every year. I don't see how we could ever transition to the Japanese model. Which is a shame.

I think the optimal solution needn't and shouldn't be government designed.

To see countries like Norway where the state is subsidizing electric cars. Then meanwhile it's the state owned company Equinor still extracting huge amounts of oil for export. That oil might not get burned in Norway. But it's going to be burnt somewhere regardless how clean the energy in Norway is. Achieving clean transportation in one country doesn't mean we're solving the CO2 problem if the states are still allowing oil to be extracted and exported to other countries.

The problem is perhaps best solved by achieving renewable energy sources. Either through electricity or producing renewable (combustible) fuel sources.

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