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Re: Also remember that diesel's are now a lot cleaner
Author: BOB2
Date: 01-24-2014 - 15:05
The issues of crash worthiness safety with CNG and LNG are serious, that is why many of these demonstrations have involved "based" fleets, yard or terminal.
What is interesting is that cost not necessarily environmental factors are increasingly driving the gas fuel and electrification interest in railroads.
In the late eighties, when I started working on diesel locomotive emissions, there were no regulations on diesel trucks or trains for emissions. The typical fleet average diesel emissions for nitrous oxides (NOx) from locomotives was over 40 grams per brake horsepower hour. This is why we had to cover our cars at Taylor yard at night back in the "good old' days. NOx would mix with fog from the LA River to create acids that would eat the paint on your car, or give you a nice face peel (you could feel it burning your skin), and we were breathing that all night.
Included in that toxic locomotive emissions mix was a good dose of toxic diesel particulates, made up of a good deal of sulfur and carbon. And, I knew not just a few career rails who between smoking and this soot exposure had bad lungs.
NOx is also a precursor chemical for Ozone, or good old fashion photo-chemical smog, it mixes with high octane hydrocarbons, and sunlight to cause Ozone. We used to refer to these then unregulated sources as "mobile NOx generators", as locomotives consisted then of a small but "untouchable" "Federal" source of emissions.
New locomotives are now regulated for emissions and are now meeting tier 3 and 4 standards, with reductions in particulates, and over a 90% reduction in NOx. As a result of locomotive fleet replacement, over the last decade, this has made this a noticeably smaller source of air pollutants.
Partial gas conversion at terminals and/or partial electrification of major western mountain corridors and mainlines might make long term economic sense, and also meet emission requirements at a lower cost. Cost and ROI on reasonable long term investment risk horizon will be the test of viability for all of these options.
What is interesting is that cost not necessarily environmental factors are increasingly driving the gas fuel and electrification interest in railroads.
In the late eighties, when I started working on diesel locomotive emissions, there were no regulations on diesel trucks or trains for emissions. The typical fleet average diesel emissions for nitrous oxides (NOx) from locomotives was over 40 grams per brake horsepower hour. This is why we had to cover our cars at Taylor yard at night back in the "good old' days. NOx would mix with fog from the LA River to create acids that would eat the paint on your car, or give you a nice face peel (you could feel it burning your skin), and we were breathing that all night.
Included in that toxic locomotive emissions mix was a good dose of toxic diesel particulates, made up of a good deal of sulfur and carbon. And, I knew not just a few career rails who between smoking and this soot exposure had bad lungs.
NOx is also a precursor chemical for Ozone, or good old fashion photo-chemical smog, it mixes with high octane hydrocarbons, and sunlight to cause Ozone. We used to refer to these then unregulated sources as "mobile NOx generators", as locomotives consisted then of a small but "untouchable" "Federal" source of emissions.
New locomotives are now regulated for emissions and are now meeting tier 3 and 4 standards, with reductions in particulates, and over a 90% reduction in NOx. As a result of locomotive fleet replacement, over the last decade, this has made this a noticeably smaller source of air pollutants.
Partial gas conversion at terminals and/or partial electrification of major western mountain corridors and mainlines might make long term economic sense, and also meet emission requirements at a lower cost. Cost and ROI on reasonable long term investment risk horizon will be the test of viability for all of these options.
