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Old 2020-05-20, 19:04   #1563
kladner
 
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I have assumed that trains are less polluting than planes, even if they are burning diesel. I wonder what the comparison actually is.
It turns out that with current equipment, over 300-500 mile trips trains (Amtrak) beat planes, cars with at least 2 passengers edge out trains. The winner by far is an intercity bus, i.e. Greyhound. This in passenger-miles per gallon of fuel. Planes improve their standing over longer hauls, because takeoff uses an immense amount of fuel compared to cruising. The first graph is for current conventional equipment.

With ideal equipment all modes improve. For planes this means bigger is better, (A320 neo), if they are fully loaded with 500+ passengers. This improves efficiency from just over 40 passenger miles per gallon to somewhat over 50. For trains, California High Speed Rail is the modern example. Improvement is from about 50 p-mpg to over 90 p-mpg. Switching to a hybrid car gets you from 50+ p-mpg to the high 90s. Current Greyhound buses give about 150 p-mpg, while the improved new models get almost 200.

One note: the second graph calculated fuel in terms of gasoline equivalents based on the energy content of jet fuel or diesel.
Source: https://theicct.org/blogs/staff/plan...ounting-carbon
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Old 2020-05-20, 19:12   #1564
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Electrify the trains and then we are talking.
Or use a Tesla Semi version of a bus and things get interesting.
Switch planes to liquid CH4 and the dynamic will change quite a lot. The USAF even has the ability to aerial refuel LNG.....
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Old 2020-05-20, 20:33   #1565
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Cal High Speed is still under construction, but it will be all electric.
https://www.buildhsr.com/pdfs/HSR_Ge...cts_060418.pdf
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Old 2020-05-21, 14:26   #1566
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Quote:
Originally Posted by kladner View Post
I have assumed that trains are less polluting than planes, even if they are burning diesel. I wonder what the comparison actually is.
It turns out that with current equipment, over 300-500 mile trips trains (Amtrak) beat planes, cars with at least 2 passengers edge out trains. The winner by far is an intercity bus, i.e. Greyhound. This in passenger-miles per gallon of fuel. Planes improve their standing over longer hauls, because takeoff uses an immense amount of fuel compared to cruising. The first graph is for current conventional equipment.

With ideal equipment all modes improve. For planes this means bigger is better, (A320 neo), if they are fully loaded with 500+ passengers. This improves efficiency from just over 40 passenger miles per gallon to somewhat over 50. For trains, California High Speed Rail is the modern example. Improvement is from about 50 p-mpg to over 90 p-mpg. Switching to a hybrid car gets you from 50+ p-mpg to the high 90s. Current Greyhound buses give about 150 p-mpg, while the improved new models get almost 200.

One note: the second graph calculated fuel in terms of gasoline equivalents based on the energy content of jet fuel or diesel.
Source: https://theicct.org/blogs/staff/plan...ounting-carbon
I have seen similar comparisons in the past. There is an interesting debate in western US cities and states regarding trains vs. buses. Typically, upper middle class residents propose mass transit trains as a solution to pollution and traffic problems. However, the trains, when developed, rarely work out as planned. The trains are too expensive to run on schedules that work for the people that would use them. People continue to use their cars and the local government spends beaucoup money maintaining its boondoggle. A good bus system is usually the ideal solution, but too many residents eschew the bus ("too many poor people on those").
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Old 2020-05-21, 15:19   #1567
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It seems that US residents have difficulty accepting mass transit in general. I suppose this somewhat excludes areas which have had extensive transit systems for a long time. On the other hand, places which have been auto-centric tend to stay that way. There's a mythology of the "freedom and independence" that a car supposedly confers. Also, as you say, the whole class consciousness thing does rest on a mindset that relegates transit to the "lower" classes.

It is worth recalling that the LA region had an extensive interurban rail system at one time. General Motors bought the rail system and trashed it so as to sell more buses and cars.

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Old 2020-05-21, 16:41   #1568
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Quote:
Originally Posted by kladner View Post
It is worth recalling that the LA region had an extensive interurban rail system at one time. General Motors bought the rail system and trashed it so as to sell more buses and cars.
That is not a realistic picture. GM owned other mass transit systems at the time and didn't trash them. There was the post war boom. There was the fact the Pacific Electric was on the decline and much of the system needed a large amount of maintenance. There was not just PE, there was a Los Angeles City Line, and some other Mass Transit systems.
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Old 2020-05-21, 21:47   #1569
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Quote:
Originally Posted by Uncwilly View Post
That is not a realistic picture. GM owned other mass transit systems at the time and didn't trash them. There was the post war boom. There was the fact the Pacific Electric was on the decline and much of the system needed a large amount of maintenance. There was not just PE, there was a Los Angeles City Line, and some other Mass Transit systems.
I stand corrected. Can we compare the outlay which might have been required for the transit system to be rehabbed and enhanced; with the costs of building freeways?

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Old 2020-05-21, 22:19   #1570
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Quote:
Originally Posted by kladner View Post
I stand corrected. Can we compare the outlay which might have been required for the transit system to be rehabbed and enhanced; with the costs of building freeways?
The freeways are State and National, not owned by a private company.
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Old 2020-05-21, 22:39   #1571
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Quote:
Originally Posted by Uncwilly View Post
The freeways are State and National, not owned by a private company.
But the state and the feds would still be very much influenced by a behemoth like GM. Regardless of ownership, there is still a question of allocation of resources. Lord knows we are seeing plenty of "bailouts" of companies which are not even near the rocks, much less on them, these days.
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Old 2020-05-21, 22:52   #1572
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Quote:
Originally Posted by kladner View Post
But the state and the feds would still be very much influenced by a behemoth like GM.
Are you familiar with the nation defense roads? That all started happening 1956, after much of the decline had already happened.

https://en.wikipedia.org/wiki/Genera...car_conspiracy
https://en.wikipedia.org/wiki/Pacific_Electric#Decline
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Old 2020-05-22, 06:26   #1573
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Quote:
Originally Posted by Uncwilly View Post
The freeways are State and National, not owned by a private company.
Non sequitur.

The question was about the outlay, not the ownership.
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