5 ms·

Electrifying tracks can be more difficult than it first seems. For example in the UK on certain lines you have to replace most road bridges that go over the tra

by joshlk 4y ago

Electrifying tracks can be more difficult than it first seems. For example in the UK on certain lines you have to replace most road bridges that go over the track. The bridges are not high enough to fit electric lines underneath. Tunnels can also have the same problem.

ChuckNorris89 4y ago
Some bridges and tunnels are also not electrified in Austria but electric trains still pass through them on their massive inertia alone. It's really not a big issue for trains.
- pmyteh 4y ago
  They're doing that more here (putting neutral sections with reduced clearance under bridges) but it doesn't save everything. A major disadvantage of being early to the railway game is that we have amongst the most restrictive structure gauge in the world. It also turns out that we've repeatedly stopped and restarted our electrification campaign over the last hundred years, such that we have little persistent expertise and excessive costs per km. So it's not just tunnels and bridges.
pmyteh 4y ago
This. The capital costs are huge, such that it only makes marginal sense on a financial basis alone. You get further factoring in service improvements (lighter trains without diesel engines -> faster acceleration -> shorter journey tines), the societal benefits of decarbonisation, and electric trains breaking down less often, but that only moves the viable point so far. In the extreme case, a railway which is 200 miles long and takes 3 trains a day will never have a positive financial case for electrification. So once you've electrified all the stuff that should have been done decades ago (like main lines with 10 trains an hour) and then pushed on to the marginal stuff (hourly rural lines) there's still a small core of lines left. You could just bite the bullet and electrify them anyway, or you could go with things like battery electric trains (good for short distances off an electric mainline) or biodiesel/green hydrogen. The latter are likely to be cheaper.
- Arnt 4y ago
  Worth testing, anyway, and this looks like a good place to test them. Hydrogen trains might make sense even if hydrogen cars don't, since the trains run on their tracks, according to a fixed timetable, and need little new infrastructure.
  - dragontamer 4y ago
    The issue with Hydrogen is its storage technology. It requires a high pressure (300-bar minimum, 700-bar ideal) environment... or cryogenics to store compact liquid hydrogen. Building a small, personal, car-tank that withstands 700-bar of pressure and survives typical car accidents is... really difficult? However, building a large train-tank that withstands a typical derailment is far easier. ------ I don't think Hydrogen will ever be useful for personal cars. The pressure requirements / storage requirements look rather insane. I know there's groups working with carbon-fiber designs and other advanced materials, but those are really expensive. Larger trains / trucks can just use standard steel to contain the Hydrogen at 700-bar of pressure (because a bigger tank is easier to scale).
    - Arnt 4y ago
      Oh, I thought distribution was the main issue. Trains needing only one supply point, as opposed to masses of gas stations along the roads. TIL.
      - dragontamer 4y ago
        I mean, Toyota and Hyundai are making personal H2 vehicles. But they're expensive, very expensive, because those storage tanks are extremely sophisticated. Unless those storage tank costs come down by a LOT, I don't think H2 cars will compete reasonably against other technologies (Hybrid, PHEV, or EVs) ----- $50,000 for an H2 vehicle with only 180 horsepower engine is really meh.
thematrixturtle 4y ago
As a reference point for just how expensive, the Caltrain electrification project in SF is currently estimated at $2.44 billion dollars for 82 km of track, and still climbing. And this is for what's almost a best-case infrastructurally: flat land, few bridges or overpasses, etc. (But, admittedly, what just might the world's worst regulatory environment.)
- Symbiote 4y ago
  Midland Main Line in England "cost given as £1.3 billion pounds and also included three station modifications at Leicester, Derby and Sheffield. 422 single track miles of wiring was supposed to occur and a total of 120 bridges modified." So roughly 340km of double-track for $1.5bn. https://en.wikipedia.org/wiki/Midland_Main_Line_railway_upgrade https://en.wikipedia.org/wiki/Midland_Main_Line_railway_upgr...
- izacus 4y ago
  American overinflated public infrastructure estimates aren't very useful for comparisons with Germany however. With the numbers US planners are spewing out, we'd never have fast train network in Switzerland or high-speed rail across Italy, France or Spain.
- MagnumOpus 4y ago
  $30 million per km (even if double-tracked) is exorbitant and can only be explained through entities who don't care spending Other People's Money. The UK government estimates £600k/track-km, so even in the US with high wages it should be doable at $2 million/km per track if budgeted carefully...
  - avn2109 4y ago
    Wait till you learn about the subways in NYC which they dig for comfortably over a billion dollars per mile...
- zbrozek 4y ago
  It would be interesting to know what drives cost gaps versus other jurisdictions.
jbu 4y ago
If the train had enough battery to get through the tunnel, but was charged on the main line, that would work wouldn't it?
- VaxWithSex 4y ago
  Yes and Deutsch Bahn is doing exactly this. Source: https://www.tagesschau.de/wirtschaft/deutsche-bahn-siemens-wasserstoff-zug-brennstoffzelle-101.html https://www.tagesschau.de/wirtschaft/deutsche-bahn-siemens-w...
danw1979 4y ago
Anecdata: as a regular commuter on the east coast main line in the UK for several years, a very common source of service interruption was blamed on overhead cable problems. From an engineering perspective the complication of the track electrical infrastructure and pantograph seem inferior to a hydrogen tank and fuel cells. Far less actual stuff to build and maintain.
- Symbiote 4y ago
  That line was electrified as cheaply as possible. It's not a problem elsewhere. http://www.rail.co.uk/rail-news/ecml-suffers-another-failure/ http://www.rail.co.uk/rail-news/ecml-suffers-another-failure...
- VaxWithSex 4y ago
  Anecdata from Germany: that never happend to me. Mostly trees falling on the tracks.
- pmyteh 4y ago
  The East Coast Main Line is prone to dewirement (where the pantograph comes off the catenary and normally gets tangled and brings down the wire) at an unusually high rate. The folk wisdom is that the use of wired headspans instead of rigid portals, combined with a long distance between stanchions, makes it fragile. I don't know the extent to which that's true. Set against that, the miles per technical incident for electric trains are about twice that for diesel, and a train breaking down on the ECML is also disruptive, if not obviously infrastructural...
ZeroGravitas 4y ago
Batteries can get you through the places where its hard/costly to directly electrify. The two techs are complementary. You see this on tram systems where bridges or junctions conplicate the overhead wires.

by joshlk 4y ago

ChuckNorris89 4y ago

Some bridges and tunnels are also not electrified in Austria but electric trains still pass through them on their massive inertia alone. It's really not a big issue for trains.

pmyteh 4y ago
They're doing that more here (putting neutral sections with reduced clearance under bridges) but it doesn't save everything. A major disadvantage of being early to the railway game is that we have amongst the most restrictive structure gauge in the world. It also turns out that we've repeatedly stopped and restarted our electrification campaign over the last hundred years, such that we have little persistent expertise and excessive costs per km. So it's not just tunnels and bridges.

pmyteh 4y ago

This. The capital costs are huge, such that it only makes marginal sense on a financial basis alone. You get further factoring in service improvements (lighter trains without diesel engines -> faster acceleration -> shorter journey tines), the societal benefits of decarbonisation, and electric trains breaking down less often, but that only moves the viable point so far. In the extreme case, a railway which is 200 miles long and takes 3 trains a day will never have a positive financial case for electrification. So once you've electrified all the stuff that should have been done decades ago (like main lines with 10 trains an hour) and then pushed on to the marginal stuff (hourly rural lines) there's still a small core of lines left. You could just bite the bullet and electrify them anyway, or you could go with things like battery electric trains (good for short distances off an electric mainline) or biodiesel/green hydrogen. The latter are likely to be cheaper.

Arnt 4y ago
Worth testing, anyway, and this looks like a good place to test them. Hydrogen trains might make sense even if hydrogen cars don't, since the trains run on their tracks, according to a fixed timetable, and need little new infrastructure.
- dragontamer 4y ago
  The issue with Hydrogen is its storage technology. It requires a high pressure (300-bar minimum, 700-bar ideal) environment... or cryogenics to store compact liquid hydrogen. Building a small, personal, car-tank that withstands 700-bar of pressure and survives typical car accidents is... really difficult? However, building a large train-tank that withstands a typical derailment is far easier. ------ I don't think Hydrogen will ever be useful for personal cars. The pressure requirements / storage requirements look rather insane. I know there's groups working with carbon-fiber designs and other advanced materials, but those are really expensive. Larger trains / trucks can just use standard steel to contain the Hydrogen at 700-bar of pressure (because a bigger tank is easier to scale).
  - Arnt 4y ago
    Oh, I thought distribution was the main issue. Trains needing only one supply point, as opposed to masses of gas stations along the roads. TIL.
    - dragontamer 4y ago
      I mean, Toyota and Hyundai are making personal H2 vehicles. But they're expensive, very expensive, because those storage tanks are extremely sophisticated. Unless those storage tank costs come down by a LOT, I don't think H2 cars will compete reasonably against other technologies (Hybrid, PHEV, or EVs) ----- $50,000 for an H2 vehicle with only 180 horsepower engine is really meh.

thematrixturtle 4y ago

As a reference point for just how expensive, the Caltrain electrification project in SF is currently estimated at $2.44 billion dollars for 82 km of track, and still climbing. And this is for what's almost a best-case infrastructurally: flat land, few bridges or overpasses, etc. (But, admittedly, what just might the world's worst regulatory environment.)

Symbiote 4y ago
Midland Main Line in England "cost given as £1.3 billion pounds and also included three station modifications at Leicester, Derby and Sheffield. 422 single track miles of wiring was supposed to occur and a total of 120 bridges modified." So roughly 340km of double-track for $1.5bn. https://en.wikipedia.org/wiki/Midland_Main_Line_railway_upgrade https://en.wikipedia.org/wiki/Midland_Main_Line_railway_upgr...
izacus 4y ago
American overinflated public infrastructure estimates aren't very useful for comparisons with Germany however. With the numbers US planners are spewing out, we'd never have fast train network in Switzerland or high-speed rail across Italy, France or Spain.
MagnumOpus 4y ago
$30 million per km (even if double-tracked) is exorbitant and can only be explained through entities who don't care spending Other People's Money. The UK government estimates £600k/track-km, so even in the US with high wages it should be doable at $2 million/km per track if budgeted carefully...
- avn2109 4y ago
  Wait till you learn about the subways in NYC which they dig for comfortably over a billion dollars per mile...
zbrozek 4y ago
It would be interesting to know what drives cost gaps versus other jurisdictions.

jbu 4y ago

If the train had enough battery to get through the tunnel, but was charged on the main line, that would work wouldn't it?

VaxWithSex 4y ago
Yes and Deutsch Bahn is doing exactly this. Source: https://www.tagesschau.de/wirtschaft/deutsche-bahn-siemens-wasserstoff-zug-brennstoffzelle-101.html https://www.tagesschau.de/wirtschaft/deutsche-bahn-siemens-w...

danw1979 4y ago

Anecdata: as a regular commuter on the east coast main line in the UK for several years, a very common source of service interruption was blamed on overhead cable problems. From an engineering perspective the complication of the track electrical infrastructure and pantograph seem inferior to a hydrogen tank and fuel cells. Far less actual stuff to build and maintain.

Symbiote 4y ago
That line was electrified as cheaply as possible. It's not a problem elsewhere. http://www.rail.co.uk/rail-news/ecml-suffers-another-failure/ http://www.rail.co.uk/rail-news/ecml-suffers-another-failure...
VaxWithSex 4y ago
Anecdata from Germany: that never happend to me. Mostly trees falling on the tracks.
pmyteh 4y ago
The East Coast Main Line is prone to dewirement (where the pantograph comes off the catenary and normally gets tangled and brings down the wire) at an unusually high rate. The folk wisdom is that the use of wired headspans instead of rigid portals, combined with a long distance between stanchions, makes it fragile. I don't know the extent to which that's true. Set against that, the miles per technical incident for electric trains are about twice that for diesel, and a train breaking down on the ECML is also disruptive, if not obviously infrastructural...

ZeroGravitas 4y ago

Batteries can get you through the places where its hard/costly to directly electrify. The two techs are complementary. You see this on tram systems where bridges or junctions conplicate the overhead wires.