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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

#231

Post by masklinn »

mikekchar wrote: post #219
fyfy18 wrote: post #207

Earlier quoted context omitted.

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.…

> 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).

OTOH between Macon (pop 34000) and Lyon (pop 500000) there is up to 4 trains / hour at commute times (1 an hour otherwise), over a slightly longer distance.

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

#232

Post by hvidgaard »

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…

If we take the hypothetical electric locomotive with a battery pack, it would probably decrease the peak load on the lines. You only need maximum power at acceleration and climb. The battery is perfectly capable at helping with the peaks, while recharging during the cruise when the power demand is low.

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

#233

Post by masklinn »

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.

The point they were making is that the train would go on batteries for the bits of the route which can't be electrified (e.g. too low tunnels), the track would otherwise be normally electrified, the battery would only be necessary to cross between electrified sections of the track.

Similar to the battery-equipped dual-mode trolleybuses increasingly getting developed / deployed[0] allowing both point-charging at stops and more independence from overhead line (so trolleys can more easily be rerouted, or can serve increasingly longer sections without overhead lines).

[0] they've existed since the 30s but mostly electric / ICE

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

#234

Post by michaelt »

jcranmer wrote: post #183
rhizome wrote: post #146

Earlier quoted context omitted.

At the dawn of the age of rail, Germany had double the US population in an area about the size of Montana. There were a lot of people who wanted to move around way before cars were a factor, so you see much, much better rail systems in Europe.

Probably a bigger factor is that, in the early 1940s, virtually the entire infrastructure of Europe was destroyed. In March 1945, there were no operational bridges across the entire length of the Rhine river. All of that infrastructure was rebuilt in the late 1940s and the 1950s to then-modern high speed standards; by contrast, the US has to make do with infrastructure upgraded at great cost around the 1910s.

Europe also had a big military imperative to build railways pre-WW1: Trains let you move your forces faster, so you can build up a concentration of forces in one location to attack or reinforce a defensive line.

So no state in continental Europe wanted to be on the losing side of a railway gap.

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

#235

Post by rhizome »

jcranmer wrote: post #183
rhizome wrote: post #146

Earlier quoted context omitted.

At the dawn of the age of rail, Germany had double the US population in an area about the size of Montana. There were a lot of people who wanted to move around way before cars were a factor, so you see much, much better rail systems in Europe.

Probably a bigger factor is that, in the early 1940s, virtually the entire infrastructure of Europe was destroyed. In March 1945, there were no operational bridges across the entire length of the Rhine river. All of that infrastructure was rebuilt in the late 1940s and the 1950s to then-modern high speed standards; by contrast, the US has to make do with infrastructure upgraded at great cost around the 1910s.

Before WWII Great Britain, Germany, and France all had about twice the rail they have now . After the war, cars and trucking made a big difference and system length decreased fairly steadily as a result because lots of track got rebuilt as roads.

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

#236

Post by pjc50 »

mabbo wrote: post #112

My wife and I took a trip to the middle of nowhere in Wales last fall. Train to Cardiff from London, then from Cardiff to our little cottage in the Pembrokeshire coast, I drove for 2+ hours in a rental car, learning to drive on the left. The day after we arrived, we learned we could have caught a train to Fishguard, a tiny village nearby, and then the local bus would have gotten us within a ten minute walk from our r…

Yes and no; as a Brit I would probably have chosen a car for that trip, because local buses are infrequent and unreliable. Trips other than via London are often easier by car.

The UK never really had the space to develop US-style suburban sprawl, even in its designed car-centric new towns like Milton Keynes.

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

#238

Post by swish_bob »

pmart123 wrote: post #35
temp-dude-87844 wrote: post #8

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…

Another issue is the local public transportation in most US cities isn’t adequate so travelers want to transport their vehicle with them. Although, rideshare services help alleviate this issue.

Motorail? (https://en.wikipedia.org/wiki/Motorail)

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

#239

Post by esotericn »

As others have stated, the layout of a city presents enormous issues WRT public transport rollout.

If you take a train into a major metropolitan city like London you're sorted. You have a plethora of transport options available. For an area of at least five miles around the mainline station you come in to, buses are very frequent, a subway probably exists, other trains will exist, taxis/Uber will be easy, and so on.

Contrast that with taking a train to a random Northern town in the UK. You can get there, sure. Now what? You're miles walk from anything, it's all a big car-like suburban layout unless the specific thing you're visiting happens to be in the old town.

I generally tend to drive when visiting family for that reason alone, because otherwise it takes four or five times longer (not an exaggeration at all) to get anywhere once you're there. A 10-15 minute drive could be a 50 minute bus journey.

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

#240

Post by aj_g »

maccard wrote: post #229

My biggest issue is train costs. I live in Edinburgh, and I can fly to London in 6 weeks for £19, or I can get the train for £160. The overall travel time is roughly the same, but at 6 times the price it can be very hard to justify. Especially when you have to travel with more than one person.

Agreed--I want to take trains, but when I can fly somewhere and buy 10x the carbon offsets for the difference between the plane/train costs, well...I'm going to fly.
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