4 ms·

I wonder what the CO2/(passenger*km) looks like for trains at those speeds, especially if you add in some amortized cost for all the infrastructure the train ne

I wonder what the CO2/(passenger*km) looks like for trains at those speeds, especially if you add in some amortized cost for all the infrastructure the train needs

dalbasal 5y ago
How do you amortize CO2?
- GrantZvolsky 5y ago
  CO2/(passenger*km), not CO2.
- natpalmer1776 5y ago
  You take out a loan from the CO2 bank with CO2 bring charged as interest, and then slowly pay it back over the course of a few decades. How much you pay back is something the atom counters figure out, I'm naught but a humble Oxygen farmer.
- adrianN 5y ago
  You guesstimate how much CO2 was released during construction, and divide by the expected lifetime of the structure and add a guesstimate for the CO2 used for maintenance.
- xster 5y ago
  Also, how do you amortize the alternatives? e.g. the airports, getting to the airports (which are further from city centers than train stations), etc?
fvdessen 5y ago
I remember some paper looking at this question, and if you took into account the train infrastructure, planes were not too far off. But train has other advantages such as reduced noise pollution, being able to bring you right to your destination, and not being hijackable into buildings.
- adrianN 5y ago
  The big advantage is that you can easily run trains off of CO2-neutral electricity. The answer to my question heavily depends on how the electricity mix looks like.
  - credit_guy 5y ago
    > The answer to my question heavily depends on how the electricity mix looks like. Yes, but the electricity mix will continue to move towards more renewables. Air travel will continue to use fossil fuels.
    - sudosysgen 5y ago
      Indeed, there is pretty much 0 feasible way of moving air travel to carbon neutral energy. Even biofuels are simply not economically feasible and may well never be, and batteries are a no-go.
- melling 5y ago
  The train infrastructure over 50 years? I doubt if air travel is even close to as environmentally friendly The real problem with not doing the trains is the right of ways become difficult. California wanted to build high-speed rail in the 1970s but the car culture won. They kept expanding the highways. Now they can’t build directly between SF and LA, for example. People also overlook that trains can make a few stops along the way. China transports over a billion passengers a year by rail. Put them in the air
  - antihero 5y ago
    Also by building dedicated express and high speed train lines (such as we're doing in the UK with HS2) you enable the stopping services to be far more efficient and frequent, which means more people can use them.
  - giantrobot 5y ago
    > Now they can’t build directly between SF and LA, for example. Geography and geology make building HSR between LA and SF difficult. You'd need to bore through a bunch of mountains to get to the Central Valley and then bore through more mountains to get to the SFBA.
frereubu 5y ago
This is an interesting read on that subject: https://www.lowtechmagazine.com/2013/12/high-speed-trains-are-killing-the-european-railway-network.html https://www.lowtechmagazine.com/2013/12/high-speed-trains-ar... One of the many complexities involved is the fact that high-speed trains on existing lines take up much more track space and push out slower-moving trains which link up the smaller stations. So city-to-city is fine, but towns and below get a reduced service, leading to more car traffic to get to stations (and more pure car journeys). This makes the point that the more trains are powered by clean electricity though, the better: https://www.lowtechmagazine.com/2007/04/planes-on-whe-1.html https://www.lowtechmagazine.com/2007/04/planes-on-whe-1.html
jillesvangurp 5y ago
Depends; if you use renewable energy, operating it could pretty much be neutral. Given that this is in China, I would expect them to mostly power this with renewables (wind, hydro, or nuclear). They do still build a lot of coal as well of course. Steel production for the infrastructure could long term also be a lot cleaner but is short term likely to have a substantial CO2 footprint. But that would be similar to other high speed rail options. Probably, over the life time of the installation, it would be quite good.
bluGill 5y ago
Don't forget that airplanes spend their time at altitude where this is much less wind resistance.

I wonder what the CO2/(passenger*km) looks like for trains at those speeds, especially if you add in some amortized cost for all the infrastructure the train needs

dalbasal 5y ago

How do you amortize CO2?

GrantZvolsky 5y ago
CO2/(passenger*km), not CO2.
natpalmer1776 5y ago
You take out a loan from the CO2 bank with CO2 bring charged as interest, and then slowly pay it back over the course of a few decades. How much you pay back is something the atom counters figure out, I'm naught but a humble Oxygen farmer.
adrianN 5y ago
You guesstimate how much CO2 was released during construction, and divide by the expected lifetime of the structure and add a guesstimate for the CO2 used for maintenance.
xster 5y ago
Also, how do you amortize the alternatives? e.g. the airports, getting to the airports (which are further from city centers than train stations), etc?

fvdessen 5y ago

I remember some paper looking at this question, and if you took into account the train infrastructure, planes were not too far off. But train has other advantages such as reduced noise pollution, being able to bring you right to your destination, and not being hijackable into buildings.

adrianN 5y ago
The big advantage is that you can easily run trains off of CO2-neutral electricity. The answer to my question heavily depends on how the electricity mix looks like.
- credit_guy 5y ago
  > The answer to my question heavily depends on how the electricity mix looks like. Yes, but the electricity mix will continue to move towards more renewables. Air travel will continue to use fossil fuels.
  - sudosysgen 5y ago
    Indeed, there is pretty much 0 feasible way of moving air travel to carbon neutral energy. Even biofuels are simply not economically feasible and may well never be, and batteries are a no-go.
melling 5y ago
The train infrastructure over 50 years? I doubt if air travel is even close to as environmentally friendly The real problem with not doing the trains is the right of ways become difficult. California wanted to build high-speed rail in the 1970s but the car culture won. They kept expanding the highways. Now they can’t build directly between SF and LA, for example. People also overlook that trains can make a few stops along the way. China transports over a billion passengers a year by rail. Put them in the air
- antihero 5y ago
  Also by building dedicated express and high speed train lines (such as we're doing in the UK with HS2) you enable the stopping services to be far more efficient and frequent, which means more people can use them.
- giantrobot 5y ago
  > Now they can’t build directly between SF and LA, for example. Geography and geology make building HSR between LA and SF difficult. You'd need to bore through a bunch of mountains to get to the Central Valley and then bore through more mountains to get to the SFBA.

frereubu 5y ago

This is an interesting read on that subject: https://www.lowtechmagazine.com/2013/12/high-speed-trains-are-killing-the-european-railway-network.html https://www.lowtechmagazine.com/2013/12/high-speed-trains-ar... One of the many complexities involved is the fact that high-speed trains on existing lines take up much more track space and push out slower-moving trains which link up the smaller stations. So city-to-city is fine, but towns and below get a reduced service, leading to more car traffic to get to stations (and more pure car journeys). This makes the point that the more trains are powered by clean electricity though, the better: https://www.lowtechmagazine.com/2007/04/planes-on-whe-1.html https://www.lowtechmagazine.com/2007/04/planes-on-whe-1.html

jillesvangurp 5y ago

Depends; if you use renewable energy, operating it could pretty much be neutral. Given that this is in China, I would expect them to mostly power this with renewables (wind, hydro, or nuclear). They do still build a lot of coal as well of course. Steel production for the infrastructure could long term also be a lot cleaner but is short term likely to have a substantial CO2 footprint. But that would be similar to other high speed rail options. Probably, over the life time of the installation, it would be quite good.

bluGill 5y ago

Don't forget that airplanes spend their time at altitude where this is much less wind resistance.