The Electrification discussion

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Catenary is not bad, but depending on the use case, may be an economically poor choice. For a few trains a day for a relatively short distance it is tough to make a case for something that has extensive capital and maintenance costs.
 
I really am mystified by the dislike of catenary masts - most older RR' ROW's already have (or had) lines of phone and telegraph poles strung up along them.

Only place outside of Southern England that used third rail on a large scale that I can think of is Metro North territory (for commuter, regional or mainline rail).
 
Railway are using taller rail cars now, so that is the technical reason why overhead wires are going to be unwelcome.

The system that use battery pack to run trolley are in city that are quite old and the simple poles and wires are noticeable change to the few blocks of a historic area.
 
Railway are using taller rail cars now, so that is the technical reason why overhead wires are going to be unwelcome.

The system that use battery pack to run trolley are in city that are quite old and the simple poles and wires are noticeable change to the few blocks of a historic area.
That is a non reason. India uses 25’ high catenary to clear 23’ tall double stacks. It is no big deal. US does not have any loading gauge higher than ~20’. Those are already cleared by standard height NEC catenary.
 
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The newer CARB rules pretty much rule out most new rebuilds unless it is going to 4. That is not what was suggested in the original post which was 2&3, which will not happen.
CARB won't fund it but they will allow units rebuilt to T3 to last longer than the T0 units in service now.
Railway are using taller rail cars now, so that is the technical reason why overhead wires are going to be unwelcome.
even with full plate H at 20.25ft 25kv overhead lines can be at 22ft just fine and thats without some of the UK clearance tools that allow them to get insanely close
 
I really am mystified by the dislike of catenary masts - most older RR' ROW's already have (or had) lines of phone and telegraph poles strung up along them.

Only place outside of Southern England that used third rail on a large scale that I can think of is Metro North territory (for commuter, regional or mainline rail).
I would agree with this. If there's opposition to catenary because of "viewsheds," they're nuts. Catenary electric is a mature off the shelf proven technology. Heck, if the operators are really hard up for ca$h, they'll soon be able to get surplus ACS-64s from Amtrak, but in any event, Siemens and lots of other vendors can deliver them with no need for expensive product development.
 
The building of catenary has taken an unexpected delays due to installing the cassions for the poles. Look at Caltrain's delays getting all the potholes dug. It also happened on the New Haven _ BOS construction. Potholing is labor intensive and deals with many different agencies to acknowledge their underground crossing that may not ever been reported to the owning RR. Then inspectors to attempt to verify which often is often impossible. Then a potholing contractor finds unknown utilities and catenary engineering has to relocate cassions to fit the normal 120 foot distance for constant tension catenary.

All in all a very labor intensive work.
 
Only place outside of Southern England that used third rail on a large scale that I can think of is Metro North territory (for commuter, regional or mainline rail).
Depends how you define large scale, but in Hamburg for example it is used on both the Hochbahn (metro system) as well as on local DB commuter lines (S-Bahn) and even one or two non DB regional lines that extend some way out of the city.

The UK is the only country that comes to mind where it is used on intercity routes though. There are also third-rail capabale freight engines, but this option is no used very much these days as the privatized freight companies prefer to run diesels on third rail mileage. In the medium term there are plans to convert the spine from Basingstoke to Southampton from third rail to catenary. This would require passenger trains to be dual mode. This corridor is important for freight as it accesses Southhampton docks (largest and most significant freight dock complex in the UK).
 
I would agree with this. If there's opposition to catenary because of "viewsheds," they're nuts. Catenary electric is a mature off the shelf proven technology. Heck, if the operators are really hard up for ca$h, they'll soon be able to get surplus ACS-64s from Amtrak, but in any event, Siemens and lots of other vendors can deliver them with no need for expensive product development.
yes, it's the old capex vs opex question. If you can't afford the capex then you burden yourself with higher opex. If the motivation is environmental, California ought to be providing incentives for electrification, not actively favoring alternatives.
 
Depends how you define large scale, but in Hamburg for example it is used on both the Hochbahn (metro system) as well as on local DB commuter lines (S-Bahn) and even one or two non DB regional lines that extend some way out of the city.

The UK is the only country that comes to mind where it is used on intercity routes though. There are also third-rail capabale freight engines, but this option is no used very much these days as the privatized freight companies prefer to run diesels on third rail mileage. In the medium term there are plans to convert the spine from Basingstoke to Southampton from third rail to catenary. This would require passenger trains to be dual mode. This corridor is important for freight as it accesses Southhampton docks (largest and most significant freight dock complex in the UK).
Has there been any significant route extension of third rail electrification in the Southern Region? All the electrification talk I have seen recently has been catenary based, including replacement of third rail by catenary in some routes.
 
Interesting thing about electrification that we have learned from places like Switzerland, Benelux, China, Russia and India is that there comes a tipping point in the proportion of tracks that are electrified, beyond which it becomes economical to electrify branch lines with even just one or two trains per day. India has just gone beyond that tipping point and now they are happily electrifying branches with just a few trains a day. But until you reach that point you tend to look for electrification extender technologies like battery etc. I think California has a long way to go before hitting that tipping point, and until one gets there sparse traffic branch lines will be served by various other so called zero emission technologies.
 
Interesting thing about electrification that we have learned from places like Switzerland, Benelux, China, Russia and India is that there comes a tipping point in the proportion of tracks that are electrified, beyond which it becomes economical to electrify branch lines with even just one or two trains per day. India has just gone beyond that tipping point and now they are happily electrifying branches with just a few trains a day. But until you reach that point you tend to look for electrification extender technologies like battery etc. I think California has a long way to go before hitting that tipping point, and until one gets there sparse traffic branch lines will be served by various other so called zero emission technologies.
The thing about electrifying branch lines that get two trains a day is that suddenly it becomes more economical to go to say three or four trains a day and more. If you look at old timetables from say Switzerland and the Netherlands from before and after the major electrification drives, you often find that pre electrification many branch lines had rather sparse timetables but that following electrification services were stepped up while overal cost recovery also improved or at least remained stable.

Sometimes with the hindsight of history we have a tendency to assume the lines with frequent service were the ones that got electrified because there was more traffic. In fact if you actually go back and look at old timetables you often find this is not the case, and that it was the electrification that helped these lines grow rather then vice versa. There are plenty of examples of this is Spain for example.
 
Has there been any significant route extension of third rail electrification in the Southern Region? All the electrification talk I have seen recently has been catenary based, including replacement of third rail by catenary in some routes.
The last major electrification drive on longer main lines was in the 1970s with, first the Kent Coast line, and then Bournemouth.

Since then there has been a project here and a project there, but it's more filling in gaps at low cost rather than big projects dedicated to all new long lines (which admittedly, they have run out of, I can't think of any candidates for major projects except Basingstoke to Exeter which for some reason never seems to happen even though it's a bit of a no brainer).

Projects such as Bournemouth to Weymouth are just logical infills that improve existing corridors. The same can be said of the Hastings route. This is why these were implemented and completed without much fanfare.

There are still quite a few shorter bits of lines all over the former Southern Region that have not been electrified, including connecting lines that would enable far longer electric runs at the cost of short infills. Reading to Gatwick comes to mind.
 
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Electrification does lead to better and more frequent service, but at least in India experience shows that branch line electrification did not happen out of the blue. They had to be an extension of an electrified main line or an infill, which no one bothered to even think about electrifying before the tipping point. That is what leads to the tipping point thing happening as more of the major network segments get electrified.
Projects such as Bournemouth to Weymouth are just logical infills that improve existing corridors. The same can be said of the Hastings route. This is why these were implemented and completed without much fanfare.
That is an example of electrification that happens after a tipping point has been reached.
 
The last major electrification drive on longer main lines was in the 1970s with, first the Kent Coast line, and then Bournemouth.

Since then there has been a project here and a project there, but it's more filling in gaps at low cost rather than big projects dedicated to all new long lines (which admittedly, they have run out of, I can't think of any candidates for major projects except Basingstoke to Exeter which for some reason never seems to happen even though it's a bit of a no brainer).

Projects such as Bournemouth to Weymouth are just logical infills that improve existing corridors. The same can be said of the Hastings route. This is why these were implemented and completed without much fanfare.

There are still quite a few shorter bits of lines all over the former Southern Region that have not been electrified, including connecting lines that would enable far longer electric runs at the cost of short infills. Reading to Gatwick comes to mind.
The British rail regulator has made it pretty clear that they are not going to approve new third rail electrification outside of cases like the Underground where the risk of public contact with third rail is pretty much nil.
 
Remember when the Chunnel trains used 3rd rail to Waterloo? When they changed to St. Pancras with all overhead the Chunnel trains made better time on the new route.

3rd rail has many speed limitations. Plus, the cost of multiple heavy 4-0 or bigger copper wires for 3rd rail is a factor.
 
The British rail regulator has made it pretty clear that they are not going to approve new third rail electrification outside of cases like the Underground where the risk of public contact with third rail is pretty much nil.
The British rail regulator has changed its mind more often than there have been rainy Mondays in Aberystwyth.

I wouldn't be holding my breath.

Money counts for more than high principles, and OHL electrification often requires costly rising of bridges, scraping out of tunnels etc etc.

There is no fundamental difference in the physics of electrocution between an underground line and a commuter line in the outer parts of London. Excuses that count on one system should count on the other.
 
Remember when the Chunnel trains used 3rd rail to Waterloo? When they changed to St. Pancras with all overhead the Chunnel trains made better time on the new route.

3rd rail has many speed limitations. Plus, the cost of multiple heavy 4-0 or bigger copper wires for 3rd rail is a factor.
The speed limitations were caused in part by congestion caused by sending international high priority trains down an already over-congested and curvy route that wouldn't be suitable for high speed running non matter how you electrified it. It didn't have very much to do with the electrification system. Commuter trains of 12 cars or so that accelerate hard every few minutes often have a higher power draw than a high-speed train that ambles along at constant speed.
 
The same can be said of the Hastings route.
Electrification of the Hastings route also allowed them to retire a bespoke fleet of Diesel Electric MU's that were getting to the end of their service life and were unique to this line due to a tight loading gauge, the result of several tunnels on the line that had to be reinforced thus reducing their loading gauge. The project single tracked the narrow tunnels thus allowing standard loading gauge equipment to run on the line.

Remember when the Chunnel trains used 3rd rail to Waterloo? When they changed to St. Pancras with all overhead the Chunnel trains made better time on the new route.
You can't really compare a newly built high speed line (HS1) to an existing commuter rail line. That connection was always intended as a temporary stopgap just so they could get the service up and running.
 
That is a non reason. India uses 25’ high catenary to clear 23’ tall double stacks. It is no big deal. US does not have any loading gauge higher than ~20’. Those are already cleared by standard height NEC catenary.
I gather India does so on new and purpose built routes.

All of the youtube footage I have seen furthermore appears to feature flat terrain without any tunnels, overbridges or similar structures.

Doing the same thing on an existing corridor in a densely built area with many such structures might well push up the costs by at least an order of magnitude.
 
I gather India does so on new and purpose built routes.

All of the youtube footage I have seen furthermore appears to feature flat terrain without any tunnels, overbridges or similar structures.

Doing the same thing on an existing corridor in a densely built area with many such structures might well push up the costs by at least an order of magnitude.
Experience shows that it does not increase the cost by order of magnitude. The situation in UK is however different from India because of the excessively restrictive loading gauge found in the UK.

In India the original constructions fortuitously were built with generous overhead clearance so that very often tunnels did not need any modification for 25kV electrification even on routes built in the 19th century or early 20th century. Most bridges were ope truss, so had overhead clearance anyway. Even those with girders had enough clearance in most cases.The pedestrian overbridges at stations had to be almost universally raised, but they are not all that expensive. The entire Kolkata Suburban Railway was electrified on trackage built in late 19th and early 20th century including a dozen major bridges across waterways and through more densely populated areas than can be found anywhere in the UK, In general it did not cost an order of magnitude more than electrifying flat track through the sticks.

On the other hand, for an example of trackage through Hills (which would be considered serious mountains in the UK) built in late 19th and early 20th century, consider the double track route - part of the Kolkata - Delhi route, across the Chhota Nagpur Plateau, of the Grand Chord Line involving three tunnels, built in 1906. It did not require any modification to the tunnels to electrify with 25kV in 1960s. So one could say India got lucky because of choices made by the likes of Stepehnson and Brunel who were involved in designing rights of way of the early main line construction in India, and then later followed as additions were made.

The extensive conversions from Meter Gauge were a different story. Even when original RoW were used for the converted Broad Gauge lines they were essentially built from ground up and by then it was a forgone conclusion that they would be electrified soon, so they were rebuilt with adequate clearances. And of course absolutely no new railway is built in India today without adequate clearance, and a lot of new railroad is in the process of being built.
 
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That is a non reason. India uses 25’ high catenary to clear 23’ tall double stacks. It is no big deal. US does not have any loading gauge higher than ~20’. Those are already cleared by standard height NEC catenary.
The only thing with higher CAT is the cross level of the tracks has to be kept with less differences. That way the PAN will not sway on the wire.
 
The only thing with higher CAT is the cross level of the tracks has to be kept with less differences. That way the PAN will not sway on the wire.
Indeed. I guess in the US we have grown so used to poor tracks with swaying trains that this is the first thing that comes to our mind. I have seen Videos of trains running at upto 130kph regular service and 160kph in trial runs under high catenary with no visible swaying at all. It is all in how well the track is laid and maintained and how good the suspension and running gear is of the rolling stock.
 
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