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Re: Hydrogen locomotive >> diesel
Author: Graham Buxton
Date: 01-31-2010 - 22:00
David Smith Wrote:
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> As for NOx and CO2 emissions, since railroads are
> an irrelevant source of pollution (real or
> perceived), any change in emissions from CO2 to
> NOx has near zero impact.
Per Forbes magazine, "Union Pacific consumed 1.2 billion gallons of diesel in 2008."
[www.forbes.com]
Its likely BNSF consumed a similar amount, and CSX plus NS together say another 1.5 billion, and we've got 3.9 billion gallons of diesel. Add in smaller lines and railroads easily exceed 5 billion gallons of diesel per year.
While over the road trucks certainly consume far more diesel, it strikes me as a bit odd to make an unsupported statement that "any change in [railroad] emissions from CO2 to NOx has near zero impact." A hydrogen locomotive may not be the ultimate answer, but 5 billion gallons of diesel is certainly significant in terms of potential pollution.
> 1. It is very inefficient to produce by
> electrolysis relative to refining crude oil or
> liquifying coal/biomass. Be cheaper to string
> wires over the rails than it would be using that
> electricity to convert water into hydrogen.
One of the challenges with generating "green" electricity with solar cells or wind is that there is no easy storage solution, so you either you use it immediately, or may still need "base load" generating plants. So if one was to have lots of solar/wind power, but no immediate use for that power, one option is to convert it to something that can be stored, perhaps hydrogen. In that scenario, the relative lack of efficiency of the conversion is only significant compared to alternative options for storing that excess power - use it or lose it.
At this point, hydrogen electrolysis is relatively inefficient/expensive, but that is no reason to permanently write it off. After all, Rudolph Diesel had built a working diesel engine by 1895:
[en.wikipedia.org]
but a practical diesel locomotive wasn't developed until 1925:
[en.wikipedia.org]
and even then it was another 15 years before diesel-electrics seriously challenged steam.
The evolution of the woe-be-gone original "Green Goats" and their battery problems into today's genset locomotives is a fine example of innovation building on a somewhat flawed original concept.
-------------------------------------------------------
> As for NOx and CO2 emissions, since railroads are
> an irrelevant source of pollution (real or
> perceived), any change in emissions from CO2 to
> NOx has near zero impact.
Per Forbes magazine, "Union Pacific consumed 1.2 billion gallons of diesel in 2008."
[www.forbes.com]
Its likely BNSF consumed a similar amount, and CSX plus NS together say another 1.5 billion, and we've got 3.9 billion gallons of diesel. Add in smaller lines and railroads easily exceed 5 billion gallons of diesel per year.
While over the road trucks certainly consume far more diesel, it strikes me as a bit odd to make an unsupported statement that "any change in [railroad] emissions from CO2 to NOx has near zero impact." A hydrogen locomotive may not be the ultimate answer, but 5 billion gallons of diesel is certainly significant in terms of potential pollution.
> 1. It is very inefficient to produce by
> electrolysis relative to refining crude oil or
> liquifying coal/biomass. Be cheaper to string
> wires over the rails than it would be using that
> electricity to convert water into hydrogen.
One of the challenges with generating "green" electricity with solar cells or wind is that there is no easy storage solution, so you either you use it immediately, or may still need "base load" generating plants. So if one was to have lots of solar/wind power, but no immediate use for that power, one option is to convert it to something that can be stored, perhaps hydrogen. In that scenario, the relative lack of efficiency of the conversion is only significant compared to alternative options for storing that excess power - use it or lose it.
At this point, hydrogen electrolysis is relatively inefficient/expensive, but that is no reason to permanently write it off. After all, Rudolph Diesel had built a working diesel engine by 1895:
[en.wikipedia.org]
but a practical diesel locomotive wasn't developed until 1925:
[en.wikipedia.org]
and even then it was another 15 years before diesel-electrics seriously challenged steam.
The evolution of the woe-be-gone original "Green Goats" and their battery problems into today's genset locomotives is a fine example of innovation building on a somewhat flawed original concept.
