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Re: Hydrogen trains are garbage? Usual well researched sourcing on that?
Author: FUD
Date: 03-22-2024 - 11:03
RANT WARNING. MOVE ALONG IF YOU DON'T WANT TO READ SOME RANDOM THOUGHTS. You might want to think about the last (*) paragraph, though.
I really wish Americans were more tolerant of multiple ways to solve a problem, like getting around. It always seems like we have to have and use JUST ONE WAY (or maybe 2, for cases with little overlap) - perhaps related to our tendency toward monopolies and duopolies in the economic realm?
Anyway: to a first approximation, for private travel, we have a duopoly in the US - cars, and for distances beyond what's convenient for people to drive in a day, airplanes. Rail and other forms of surface mass transportation are a footnote in the passenger transportation system, probably not even qualifying as a 1/2 in the "Rule of 2 1/2*." It doesn't have to be that way; Europe and Japan have robust road, rail, and air travel systems that (sometime uneasily) coexist. But that's the way it is, except in a few regions, in the US.
Even within modes, like rail: it's diesel or, for passengers in limited areas or in high-speed service, electric with wires. Both make sense given the emphasis, except in those limited electric passenger lines, on low-speed, heavy, infrequent freight trains (those are interrelated, of course) and low-medium speed, mostly (except in the NE Corridor), infrequent (mostly) passenger trains sharing track with those freights. Steam died because it was economically noncompetitive with diesel. Electric is now limited to higher speed trains (where the power demand exceeds what's convenient with on-board energy storage and power generation) and very frequent service, i.e. the NE Corridor and rail transit.
There's a niche developing for electric rail transit that is not fully wired. The construction and maintenance of overhead (we mostly don't do 3rd rail any more) traction power wiring is a significant expense, and it's really only justified when there will be frequent or fast service (or, ideally, both). There's a place, though, for electric propulsion without, or with discontinuous, contact wire.
Electric trains with on-board energy storage, preferably that does not involve internal combustion engines can meet those needs. The major competitors (a duopoly again!) are in use now, commercially, in buses, and are available commercially in small volumes for light rail & DMU passenger trains. They are battery and hydrogen energy storage (some researchers are playing with ammonia combustion and direct hydrogen combustion too) with electric drive. Availability for heavy freight and passenger trains is still a work in progress though; there have been test articles, but so far little commercial production.
Battery and hydrogen as energy carriers have somewhat offsetting advantages. Battery storage is more efficient "well to wheels" but is heavy, slow to recharge (an area of a lot of research that could change things if it proves out), relatively low capacity (also an area of research, but basically requiring in-service recharging to make it through a work shift or operating day), and takes a lot of space (also an area of research). There are workarounds (such as short sections of wire at stations and terminals, for in-service charging - also offered for buses). Hydrogen "recharges" quickly so even if needed during an operating day it can be done without a lot of down time, typically runs fuel cells to generate operating power so there's little if any traditional air pollution, and can be produced from renewable power and stored in bulk (for relatively short periods) easily (though with water use, which can be an issue in arid areas), but is less efficient "well to wheels," and while renewable power sourcing is possible, at present it's rare. Hydrogen can also be used in combustion engines, with minimal operational GHG production but producing some traditional air pollutants (chiefly NOx).
* There's an informal "Rule of 2 1/2" mentioned in some economic discussions that seems to often apply to other things as well. Essentially, in a system like the US has, relatively stable duopolies tend to form. They don't really compete, but must at least not obviously collude. The market usually can support other companies in the same field, that add up to about 1/2 of the market served by the smaller of the duopoly members. The same thing can happen with technologies and transportation modes. US viewpoints, though, don't seem to be able to handle the concept well; there must be a single winner of all competitions. Essentially, there must be a "silver bullet" not several ways to do something that are suitable to various conditions. Oh well.
I really wish Americans were more tolerant of multiple ways to solve a problem, like getting around. It always seems like we have to have and use JUST ONE WAY (or maybe 2, for cases with little overlap) - perhaps related to our tendency toward monopolies and duopolies in the economic realm?
Anyway: to a first approximation, for private travel, we have a duopoly in the US - cars, and for distances beyond what's convenient for people to drive in a day, airplanes. Rail and other forms of surface mass transportation are a footnote in the passenger transportation system, probably not even qualifying as a 1/2 in the "Rule of 2 1/2*." It doesn't have to be that way; Europe and Japan have robust road, rail, and air travel systems that (sometime uneasily) coexist. But that's the way it is, except in a few regions, in the US.
Even within modes, like rail: it's diesel or, for passengers in limited areas or in high-speed service, electric with wires. Both make sense given the emphasis, except in those limited electric passenger lines, on low-speed, heavy, infrequent freight trains (those are interrelated, of course) and low-medium speed, mostly (except in the NE Corridor), infrequent (mostly) passenger trains sharing track with those freights. Steam died because it was economically noncompetitive with diesel. Electric is now limited to higher speed trains (where the power demand exceeds what's convenient with on-board energy storage and power generation) and very frequent service, i.e. the NE Corridor and rail transit.
There's a niche developing for electric rail transit that is not fully wired. The construction and maintenance of overhead (we mostly don't do 3rd rail any more) traction power wiring is a significant expense, and it's really only justified when there will be frequent or fast service (or, ideally, both). There's a place, though, for electric propulsion without, or with discontinuous, contact wire.
Electric trains with on-board energy storage, preferably that does not involve internal combustion engines can meet those needs. The major competitors (a duopoly again!) are in use now, commercially, in buses, and are available commercially in small volumes for light rail & DMU passenger trains. They are battery and hydrogen energy storage (some researchers are playing with ammonia combustion and direct hydrogen combustion too) with electric drive. Availability for heavy freight and passenger trains is still a work in progress though; there have been test articles, but so far little commercial production.
Battery and hydrogen as energy carriers have somewhat offsetting advantages. Battery storage is more efficient "well to wheels" but is heavy, slow to recharge (an area of a lot of research that could change things if it proves out), relatively low capacity (also an area of research, but basically requiring in-service recharging to make it through a work shift or operating day), and takes a lot of space (also an area of research). There are workarounds (such as short sections of wire at stations and terminals, for in-service charging - also offered for buses). Hydrogen "recharges" quickly so even if needed during an operating day it can be done without a lot of down time, typically runs fuel cells to generate operating power so there's little if any traditional air pollution, and can be produced from renewable power and stored in bulk (for relatively short periods) easily (though with water use, which can be an issue in arid areas), but is less efficient "well to wheels," and while renewable power sourcing is possible, at present it's rare. Hydrogen can also be used in combustion engines, with minimal operational GHG production but producing some traditional air pollutants (chiefly NOx).
* There's an informal "Rule of 2 1/2" mentioned in some economic discussions that seems to often apply to other things as well. Essentially, in a system like the US has, relatively stable duopolies tend to form. They don't really compete, but must at least not obviously collude. The market usually can support other companies in the same field, that add up to about 1/2 of the market served by the smaller of the duopoly members. The same thing can happen with technologies and transportation modes. US viewpoints, though, don't seem to be able to handle the concept well; there must be a single winner of all competitions. Essentially, there must be a "silver bullet" not several ways to do something that are suitable to various conditions. Oh well.
