Electrification around NYC

RandallW wrote: ↑Thu Oct 24, 2024 5:03 amI understand the advantage of converting from 25Hz to 60Hz is the substation equipment is both less complex and more standard when the 60/25 Hz transition does not need to be made. Given that the only equipment in the NEC that requires 25Hz are the SEPTA Silverliner IVs and maybe some MOW equipment, once those are retired, there is no advantage to retaining 25Hz electrification anywhere on the NEC.

To add to the 25hz/60hz discussion, while you'd have to deal with Norristown and West Trenton on the Reading 25hz system in order to do freight rail electrification, conversion of the PRR 25hz system would be an absolutely monumental undertaking.

Tangent on Norristown and West Trenton. West Trenton should just be converted to 25kV/60 north of Neshaminy, and SEPTA trains on that line would need to be models that support switching on the fly. Norristown would depend on whether the Keystone Line to could be cleared to Plate H Harrisburg to GLEN to allow NS to run their Morrisville traffic via the Keystone to the Trenton Cutoff, in which case it would both require 25hz capable locomotives and wouldn't go through Norristown anymore anyway. If that isn't feasible, then NS would have to keep running Morrisville traffic via the Reading, requiring electrification of the Reading to Norristown segment, creating a conflict where either NS trains to Morrisville would have to use 25hz capable locomotives with the potential conversion of the end of the SEPTA line from the Reading 25hz system to the PRR 25hz system if extra capacity was needed, or SEPTA traffic would have to use 25kV/60 capable equipment. End tangent.

This is a press release from Amtrak about some work they are doing on the Keystone Line.

https://media.amtrak.com/2024/10/amtrak ... burg-line/

The power system is a MASSIVE system to convert, all for relatively little value. Converting to 60hz would be slightly more electrically efficient, although I would argue that using those funds to electrify additional commuter and regional rail routes in the Northeast, including NJT and LIRR would have a far bigger impact to ridership, energy use, emissions, service levels, or whatever other metric you want to measure.

There is a huge sunk investment in 25hz on the PRR system. While this particular effort would be partially re-usable on a 60hz system, with things like wire, catenary, and insulators not caring what frequency is running through them, Amtrak has made huge investments in keeping the 25hz system itself running.

25kV/60 is the gold standard now for railroad electrification, but that would require replacing even more than 12.5kV/60 due to insulators and clearance distances. The Amtrak Shore Line uses a 50kV split phase +/-25kV system, which allows for paralleling stations so that any given segment can be powered from different locations. Conversion of the PRR 25hz system would either require additional power feeds to be installed somewhere to use a 50kV split phase system with 25kV to the wire with the necessary clearance and insulator upgrades for the higher voltage, or else a wholesale rebuilding of the 25hz transmission network as a 60hz transmission network with transformers to step the power down to either 25kV/60 or 12.5kV/60.

There are also other systems that run on 25hz power, although I can't find reliable information on exactly what systems where are tied directly into it. Signal power runs at 100hz, which is frequency multiplied from 25hz, although at this point, that's probably relatively minor to convert to a commercial 60hz power supply, as we have solid state inverters that can make about anything from anything else.

All that being said, while there many be some small electrification or re-installation of PRR electrification along the NEC that should be built as 25hz to integrate with the PRR 25hz system, almost all new electrification should happen at 25kV/60, like the NJT Raritan Line to have CSAO able to access Oak Island on 25kV power. The 50kV split phase system is remarkably efficient both in capital cost to install and in operating efficiency, assuming that you don't put up a massively excessive number of catenary poles like Amtrak did on the Shore Line. The one exception that I can think of would be the Bay Ridge Branch for connection with the Cross Harbor Freight Tunnel and operation of TriBoroRX might make sense to use 12.5kV/60 to match the Hell Gate Line, which matches the MNRR New Haven Line.

NJT Main Line electrification should also be done at 25kV/60 to match the NJT Morristown Line and the future electrification of the Raritan Line. I believe the NJCL to Matawan is electrically part of Amtrak's PRR 25hz system, meaning that NJT's own electrical systems are all 25kV/60?

Nationwide, where no legacy systems exist, for freight and passenger rail electrification, 25kV/60 using 50kV split phase is the best option.

Another thought on the NJT Raritan Line. It should be extended down to West Trenton. The CSX Trenton Subdivision has plenty of room for double- or even triple-track if needed to handle both freight and passenger.

When extending it down to West Trenton, you fork it after Bridgewater. Bridgewater is close to 287 and a commercial area with a bunch of open land around it. It would make sense to me to build a transfer station at Bridgewater, and electrify at 25kV/60 down to West Trenton, and also out to Raritan with some trains on the Raritan Line west of Bridgewater set up at a DMU scoot. This way, you minimize forking of mainline electric service. If there is a lot of demand from Somerville and Raritan proper, and/or more Raritan Line trains than you would want to run to West Trenton, you could run more trains out that way, but you'd be forking more of the service and still require a transfer to go past Raritan. Forked commuter lines are generally bad, but in this case, it is a little bit of a tough one, as Raritan and Somerville are both densely populated around the train stations, much more so than the towns to the south on the way to West Trenton.

With a good connecting station at Bridgewater with cross-platform transfers, you could also alternate which train is through and which is connecting, providing through service to both lines without reducing frequency. Service continuing beyond Raritan would be diesel under the wire on the 4 miles to Bridgewater, but I think it would still make sense to electrify the 4 miles to Raritan even if only for a few trains a day so that the electrics could run directly out there from the rest of the system and utilize the existing Raritan Yard.

With a DMU scoot, you might even be able to push service out further from High Bridge, although in the whole scheme of NYC transit, this is a very small, low-density line.

Electrifying to Raritan, West Trenton, Hackettstown, Suffern, and Spring Valley would leave Port Jervis likely as loco-hauled diesel to Suffern with occasional trains to Hoboken, and High Bridge and Bay Head as DMU scoots. I don't know if there is any transit value in going beyond Hackettstown, but if there is, this is also a very small, low-density line in the whole scheme of NYC transit.

Additional electrification along with finally unifying the whole NJT system into one, fluid system that can re-balance traffic would also help with run-through with MNRR PSA at NYP and SEPTA at Trenton and West Trenton, as there would be more places for the MNRR PSA trains to go to and from, even though they would still only make up about 1/3 of total NJT trains in and out of NYP.

There have been confusing posts about the 3rd rail around NY City. Included is the subway system. You have LIRR, MNRR, NY MTA subway and maybe Amtrak. What is the exactly the nominal voltages? Are they all the same or is there differences? Is there any cross use of the DC? That may even be different between the subway's A, B, & C lines.
There are a heck of a lot of DC substations for MTA each probably with different power outputs. Here is link to MTA's 5 year capital plan.

https://new.mta.info/document/151266

west point wrote: ↑Sat Nov 09, 2024 12:27 pm There have been confusing posts about the 3rd rail around NY City. Included is the subway system. You have LIRR, MNRR, NY MTA subway and maybe Amtrak. What is the exactly the nominal voltages? Are they all the same or is there differences? Is there any cross use of the DC? That may even be different between the subway's A, B, & C lines.
There are a heck of a lot of DC substations for MTA each probably with different power outputs. Here is link to MTA's 5 year capital plan.

https://new.mta.info/document/151266

https://railroad.net/metro-north-third-rail-t33114.html

I'm guessing that there is quite a bit of fluctuation from unloaded right at the substation to loaded at substation boundaries given that the amperages involved are in some places higher than AC power transmission or distribution, owing to the much lower voltage.

As I posted elsewhere even just consideration of electrification expansion is DOA for next 4 years as we have a fossil fuel government coming into power.

MNCR & LIRR use 750VDC. The subway uses 600VDC.