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Trains are more efficient and less polluting than other transportation modes

citylab.com

261–270 of 334 posts

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

#261
Trains might be more efficient in terms of energy, but sadly they are much more expensive (here in germany), than going by car. (except for some special fares)

And the car goes anywhere, anytime and the train does not. So no wonder, also here, for most people the car is the choice number one.

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

#262
post #223

Earlier quoted context omitted.

This is a rather popular lie that ignores the facts on the ground at the time. No, the US car companies did not lobby against or destroy the streetcar industry, the growth of the suburb and government policies that promoted such growth managed to do that all on their own. The auto manufacturers just set themselves up to take advantage of this decline and the shifting of subsidies to road construction. In this case cu…

With all due respect - I don't understand this. Why would suburban growth not work with tram / local train lines that could be extended? It worked in London - one of the largest cities in the world which had to plan way ahead of time due to its historically narrow streets. I've lived in suburban London for >7 years, and frankly the only time I really needed to use the car was only to haul grocery home. Almost any oth…

A couple of things.

1. A lot of existing big cities post-WWII did, in fact, grow commuter rail out to the expanding suburbs. If you live in the suburbs (say Westchester County in NY) and work at a bank in Manhattan, there is pretty good rail service.

2. But, a lot of the suburban expansion also included companies locating out in the suburbs. For a variety of reasons (including "white flight") a lot of cities became unpopular places for professionals to live so it made sense to locate companies where the people were. NYC almost went bankrupt. Boston was losing population into the 90s. So, for a significant period of time, you had a lot of people dispersed around suburbs (and still do) and that's hard to accommodate with transit.

In Boston, for example, there was not a single major tech employer in the city by the mid 90s or so--when Teradyne moved out--all the "Route 128" companies and others were in the suburbs/exurbs. (I would bet that, at least leaving out biotech/pharma, most tech employment in the Boston area is still in the suburbs--as indeed it is in the Bay Area.)

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

#263
The figures given in on the site are taken from actual usage and so include the fact that buses tend to stop and go more than trains, are less likely to be full, etc. That's a useful view but it's good to look at the physics based maximum efficiency when full view too. I really, really recommend Sustainable Energy Without the Hot Air[1] for getting a good sense of the numbers right now the chart on vehicle efficiencies[2]

[1]https://www.withouthotair.com/

[2]https://www.withouthotair.com/c20/page_128.shtml

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

#264
post #79

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. Since externalities aren't priced in, diesel-electric locomotives haul most trains in the US. More passenger rail isn't really being built in the US, because the capital expenditures of doing s…

You are correct to point out that governments subsidize roads, making this an unfair compare. Trucking is built on the highway system, a massive capital expenditure which is completely paid for by taxpayers as a gift to the trucking industry. Massive capital expenditures are often part and parcel of transportation infrastructure; what's different here is the political will to fund it.

Calling it a gift to the trucking industry implies there wasn't originally a strategic motivation to getting it done and that individuals don't also greatly benefit. Trucking is a business with razor thin margins so that "gift" very much gets spread around. Sure cars are bad for the environment but pretending that the interstate system doesn't greatly benefit basically everyone in the country is foolhardy.

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

#265
post #215

Earlier quoted context omitted.

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.

Yep, rail road is hard to scale down, so it's very expensive to connect every single home to rail road.

Also, rail roads are not walkable, so they cannot be shared with pedestrians, so this limitation forces create two separate roads: one for pedestrians, bicycles, cars, etc., and second one for rail transport. Trams can be mixed with regular road traffic, but trams cannot use regular rail roads because of different construction of rail road.

Also, rail roads are prone to Single Point of Failure problems. To prevent SPF, multiple redundant routes must be built, with lot of expensive junctions between them.

Also, you must schedule your travel.

So, we need something which 1) can be shared with regular road traffic like trams, 2) can deliver loads of cargo efficiently like rail or metro, 3) can be connected to every house like regular road, 4) can be navigated by any car at any time of day or night, 5) be cheaper than regular road for road, cart, maintenance, recycling, 6) can provide power to carts, 7) can provide navigation and scheduling service to carts, 8) be with low delay (fast).

Regular road is 1,3,4,±8. Uber is 1,3,4,5,7,8. Aero-taxi is 1,3,4,±5,7,8. Trams is 1,2,6,7. Metro is 2,6,7. Rail is 2,5,6,7.

Edit: Tram-train is 1,2,5,6,7.

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

#266
post #194

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…

A TGV can take over 12MW. It uses a single contact feeding the two power cars at each end of the train to avoid problems with oscillations in the overhead line at high speeds.

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

#267

Earlier quoted context omitted.

Rail is publically funded pretty much everywhere (i.e. it doesn't make a direct profit if you factor in infrastruture costs). Just because the market won't pay for it doesn't mean that it isn't worthwhile.

Japanese rail is almost all privately owned and operated, to the best of my knowledge. It makes its profits off of capturing the increase in land value by being the landlord around its rail stations. That model is illegal in the US so rail has to be subsidised.

That is also how the trans-continental railroad in America was financed.

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

#268
post #74

Earlier quoted context omitted.

Does it have to be maglev? Does it have to be that slow? Modern trains with wheels on rails are typically between 200 and 300 km/h: https://www.eesi.org/papers/view/fact-sheet-high-speed-rail-... *edit: replaced old link with a better one.

Parent commenter said, "maglev", so I stayed on that train of thought.

The high-speed maglev goes close to 300 mph. The low-speed is cheaper to run.

I doubt if you’d want to build a low-speed maglev between cities that are 400 miles apart.

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

#269

Trains might be more efficient in terms of energy, but sadly they are much more expensive (here in germany), than going by car. (except for some special fares) And the car goes anywhere, anytime and the train does not. So no wonder, also here, for most people the car is the choice number one.

Does anyone know a study that would look into all the implicit subsidies? Externalities in terms of environmental impact, building of roads/rails from general taxes, direct subsidies. Maybe cars wouldn’t be as cheap if all these things would be taken into account.

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

#270

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…

One possibility is a diesel-electric locomotive that also has a pickup on the top. That way part of the lines can be electrified, and the diesel fills in the gaps.

I have also thought of that. For example, a 10MW locomotive with CAT C32 as a backup diesel would be a good freight combo. CAT C32 has an intermittent duty rating of 1800hp@2100rpm and continuous duty rating of 1350hp@1800rpm. You would still have more than 1MW of power in tracks without OHLE.
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