Wacky idea for dual modes - third rail HEP?

David Benton wrote: ↑Tue Mar 01, 2022 4:59 am Sounds more like the under /over rail difference is more of a problem, and politics.

The Amtrak P32s can and have operated with both overrunning and under running third rail as they have operated into both Penn and GCT.

STrRedWolf wrote: ↑Tue Mar 01, 2022 9:46 am I have a big question.

Why diesel for motive power and electric third rail for the rest if you're concerned about emissions? Why not electric all over the place? Can't they run catenary all the way up?

Of course, there's one problem with the Empire service: the swing bridge north of Penn. But you may be able to get away with it if there's a battery system on it.

My impression is the original question was more about if (and how) operating procedures for existing equipment and infrastructure could be changed for incremental gains rather than a question about changing equipment or infrastructure (i.e., what can be done tomorrow and not in three years?).

STrRedWolf wrote: ↑Tue Mar 01, 2022 9:46 am

I have a big question.

Why diesel for motive power and electric third rail for the rest if you're concerned about emissions? Why not electric all over the place? Can't they run catenary all the way up?

Of course, there's one problem with the Empire service: the swing bridge north of Penn. But you may be able to get away with it if there's a battery system on it.

Battery / Cat -3rd rail is an ideal solution. The battery charges when on cat , then fills in during the gaps.. You can incrementally add Cat, (I.e at stations, where the train is accelerating / stopping ), and eventually extend the battery operation range. You can do the same thing with a stop/start diesel .Many battery Emu/ dmu , are modular ,so you can take out battery /diesel modules if / when electrification is extended.
I don't know how much emphasis is on reducing carbon emissions for Amtrak, maybe today's oil price would add extra impetus.

STrRedWolf wrote: ↑Tue Mar 01, 2022 9:46 am

David Benton wrote: ↑Tue Mar 01, 2022 4:59 am single phase can be converted to 3 phase, they do the conversion when the waveform passes through zero volts,so it doesnt require as heavy a "switchgear"( mosfets or other transistors) as would be the case with higher voltages.
Inverters convert power to d.c anyway , and chop it up to the required a.c hz and voltage , so starting with d.c actually saves a step . Pretty much anything is possible with modern electronics.
Sounds more like the under /over rail difference is more of a problem, and politics.
however Amtrak will want to improve its carbon footprint , currently not much better than the private auto , and higher than a bus ) , so small gains such as this may become desirable.

I have a big question.

Why diesel for motive power and electric third rail for the rest if you're concerned about emissions? Why not electric all over the place? Can't they run catenary all the way up?

Of course, there's one problem with the Empire service: the swing bridge north of Penn. But you may be able to get away with it if there's a battery system on it.

In a land long ago and far away the NYCRR did a study on hanging wire from Croton Harmon (were the 3rd rail ends) to Buffalo. They came to the conclusion it was cost prohibitive back then when labor was cheap. Now you have Metro North who most certainly isn't going to pay for catenary and NYS doesn't have the money. Traveling a little further north, along with your money issues you will hear the calls of the ever present NIMBY. People who live along the river paid big $$$$$ to do so. They will not want it spoiled by cat poles and wire. Spuytin Duyvel bridge is the least of the issues.

eolesen wrote: ↑Tue Feb 22, 2022 5:46 pm Well, third rail is Direct Current.... HEP is Alternating Current.

LIRR's trainline HEP used with diesel hauled push-pull cars, circa 1970s thru around 2000, was 600 VDC. I believe it was unique in USA passenger service.

Railjunkie wrote: ↑Wed Mar 02, 2022 10:29 amIn a land long ago and far away, the NYCRR did a study on hanging wire from Croton Harmon (where the 3rd rail ends) to Buffalo. They came to the conclusion it was cost prohibitive back then when labor was cheap. Now you have Metro-North who most certainly isn’t going to pay for catenary and NYS doesn’t have the money. Traveling a little further north, along with your money issues you will hear the calls of the ever present NIMBY. People who live along the river paid big $$$$$ to do so. They will not want it spoiled by cat poles and wire. Spuyten Duyvil bridge is the least of the issues.

When exactly did the NY Central do this? and why would they consider installing an incompatible system to their long-standing third rail electrification that would require them to adopt an electric fleet like the New Haven RR (which that RR did not require to use NY Penn), not to mention one that would invite a hostile takeover from main competitor PRR? During the era when a major railroad would seriously consider electrification, their other main traction power would have been steam power, whose operating costs depending on volume hauled by a particular railroad line were considerably higher than electric; and diesel-electric would not have given enough of an impetus to further consider electrification in any cost-benefit analysis. (And the end of third rail back in the era when such considerations would have affected the NYC most was Croton North, actually.)

I have heard the NIMBY excuse before, and if (alleged) NIMBYs are not bothered by views obscured by high-voltage pylons, then catenary wire on adjacent railroads would be the least of their worries versus property values, property tax assessments and quality-of-life issues in their immediate neighborhoods.

To answer the original question, it really only applies to LIRR. MNR and Amtrak territory doesn't really have third rail that goes beyond the places where it's required.

As for LIRR, I suspect the operational complexity is considered not worth the hassle. Would probably require new equipment too.

Um, on MNRR, third rail reaches to Croton-Harmon on the Hudson line and Southeast on the Harlem line. Diesel service continues well beyond both.