DART+ (DART Expansion)

River Suir

Dunder Mifflin wrote: »

Thanks, but I was looking for something a more bit more detailed than what's included in the General Linear Works section, unless I'm missing it. Does anyone have any experience of what the practical impact of the electrification works on the surrounding area is?

Are you looking for a detailed explanation in order to submit an objection?

Dunder Mifflin

River Suir wrote: »

Are you looking for a detailed explanation in order to submit an objection?

Not at all. I think it's an excellent idea, however I'm curious what impact (if any) it is going to have on the area around the tracks.

CatInABox

Dunder Mifflin wrote: »

Thanks, but I was looking for something a more bit more detailed than what's included in the General Linear Works section, unless I'm missing it. Does anyone have any experience of what the practical impact of the electrification works on the surrounding area is?

Network Rail have a very basic video up on it. Bear in mind that the Ireland uses a different system, which requires more substation. Realistically though, the distance between substations will be large enough that no point on the line will have to suffer the construction noise of two.

https://www.youtube.com/watch?v=rvVKge2nfyQ

This give some idea of what's needed, but as I said, it's very basic. In some areas of the DART+ project, there's going to be track levelling (Glasnevin Junction and Station), along with works surrounding the closure of level crossings. In areas where there isn't enough room to operate, I'd expect a few metres of gardens to be required, which would then be landscaped and corrected afterwards.

IE 222

Dunder Mifflin wrote: »

What’s exactly is involved with electrifying an existing train line? Is there any major construction required on the tracks or surrounding areas? Are the electricity lines the only major things needed? If anyone has any details or links to IR documents/presentations on it I’d appreciate it.

Go to the main report. There is plenty of info regarding the electrification in it around page 80. Not sure if the particular info you are looking for is there but there's a lot more detail in it.

https://www.irishrail.ie/about-us/iarnrod-eireann-projects-and-investments/DART-Programme/DART-West-Public-Consultation/DART-West-Line-Useful-Material-and-Downloads/Preliminary-Options-Selection-Report-Main-Report

IE 222

When or has a final decision been made on Connolly. The originally rejected option now seems to be the front runner. Why would a "do minimum" be supported here while it still cost €millions to implement. Can't see having the ability to terminate Sligo or Maynooth services on platform 7 been such a game changer. There will still be conflict of PPT and any Sligo line through service with Northern line traffic trying to get into platforms 5 & 6.

prinzeugen

Dunder Mifflin wrote: »

What’s exactly is involved with electrifying an existing train line? Is there any major construction required on the tracks or surrounding areas? Are the electricity lines the only major things needed? If anyone has any details or links to IR documents/presentations on it I’d appreciate it.

Two videos from the 60s & 70s that will give you an idea of what's involved.



https://m.youtube.com/watch?v=6PTsUgVxlP8
https://m.youtube.com/watch?v=UJB8w2lk9Mo


A few things are different here. Substations are 8-12 km apart and the clearances needed for 1500v DC are a lot less.

Empire o de Sun

I'm just wondering, are they not aiming to eventually have the network at 25 kV AC?
Why not build the new lines as 25 kV AC and use the new bi voltage trains on them so they can run on the new and old network. And keep the old Darts on the coastal route.

Will the new Darts be AC/DC

prinzeugen

Empire o de Sun wrote: »

I'm just wondering, are they not aiming to eventually have the network at 25 kV AC?
Why not build the new lines as 25 kV AC and use the new bi voltage trains on them so they can run on the new and old network. And keep the old Darts on the coastal route.

Will the new Darts be AC/DC

I believe new the DARTS will be 25kv AC/1500v DC. Most new electric unit trains are capable of being converted to be dual voltage anyway with modern technology.



If they ever extend the wires to Cork/Belfast then 25Kv would make sense.


At the moment, the compact nature of the DART network makes 1500v more economic long term.

Sam Russell

Is the plan not to have Bray - Maynooth. Can the trains switch from 1500 v dc to 25 kv ac on the move?

prinzeugen

Trains can switch on the move as happens going in/out of Holland. The problem is that you need have a long neutral section not just in the OHLE but on the track for return current/signaling etc.

On a high speed line that's not a problem as the train can coast through it but on a slow speed system like the DART there is a risk that the train could come to a stand in the neutral section and become stranded.

Sam Russell

prinzeugen wrote: »

Trains can switch on the move as happens going in/out of Holland. The problem is that you need have a long neutral section not just in the OHLE but on the track for return current/signaling etc.

On a high speed line that's not a problem as the train can coast through it but on a slow speed system like the DART there is a risk that the train could come to a stand in the neutral section and become stranded.

Sounds tricky - would those ***** that set out to create mayhem try to stop the train in the gap? I think we might need battery back up of some sort.

loyatemu

Sam Russell wrote: »

Sounds tricky - would those ***** that set out to create mayhem try to stop the train in the gap? I think we might need battery back up of some sort.

why, it's going to be 1500V everywhere.

Sam Russell

loyatemu wrote: »

why, it's going to be 1500V everywhere.

The suggestion was that the new lines would be 25 kv AC, with the existing lines remaining 1500 V DC. Transition would require a neutral un-powered section.

I thought it was clear. If the Dart + is going to be 1500 V DC then it is moot.

IE 222

My understanding is that the new fleet will be compatible with a switch to AC with upgrades to the trains should this be required. The Dart West will be built as 1500 v DC rather than a dual power network.

The future change to AC will only be apart of Dublin - Belfast, Cork and Galway upgrade and all trains will convert to the AC network.

Intercity electrification is at least 15 years away and is only a notion. No point creating such a complex dual voltage system for something that is a long shot of an idea.

L1011

Any switch to 25kV AC is likely to happen on higher speed straights an appreciable distance from the last close spaced commuter station; for the potential stranding reason mentioned above. I don't think there's even a suitable distance between stations before Drogheda.

Maynooth design is 1500V DC all the way and the likelyhood of putting the knitting up beyond Kilcock - ever - is slim. The other lines you might be able to argue for 25kV, but the complexity isn't worth it now.

prinzeugen

I always thought that the northern side of the Malahide estuary would be a good DC/AC changeover point in the future.



It was discussed on boards (maybe even earlier in this thread) before.



DC only for now makes economic sense but it will be interesting to see if the infrastructure works to bridges etc are done to DC standards or will they be future proofed for conversion to AC at some point in the next 100 years.

Empire o de Sun

If the DART ran on a dedicated network it could have it's own voltage that would be better for an urban system, the Berlin S-bahn is a example I know of (750 V DC). But having two different voltages on a shared network (Dart / suburban / intercity) in the future, will that not add complexity?

Thameslink in london switches from AC to a DC system. I think this is done while the train is stationary in a Farringdon station.

Looking at the map of europe, I see only a few countries use a mix voltage on mainline operations such as France and the UK.

River Suir

Empire o de Sun wrote: »

If the DART ran on a dedicated network it could have it's own voltage that would be better for an urban system, the Berlin S-bahn is a example I know of (750 V DC). But having two different voltages on a shared network (Dart / suburban / intercity) in the future, will that not add complexity?

Thameslink in london switches from AC to a DC system. I think this is done while the train is stationary in a Farringdon station.

Looking at the map of europe, I see only a few countries use a mix voltage on mainline operations such as France and the UK.

Thameslink uses 25kV AC on overhead wires from Farringdon Northwards and 550V DC on Third Rail south of Farringdon. There is a dual running section between Farringdon and City Thameslink station. As southbound trains stop at Farringdon the pantograph is lowered and the third rail shoes are connected to the rails.

In the case of Dart+ it might be more cost effective to run at 1500V DC but in the longer term it would make sense to make provision for 25kV AC. This is used on nearly all electrified lines North of the Thames and requires less substations than DC. Also my understanding is that the new Dart trains would be dual voltage so they can switch over.

The original decision to use 1500V DC was based on saving money. Like a lot of these decisions it will cost more in the long term and the AC nettle should have been grasped now,

cgcsb

With 4 tracks coming into Heuston, it would be possible to have AC on 2 of them (intercity) and DC on 2 of them (DART), that may impact operational flexibility though in terms of some DARTs terminating at Heuston and others continuing on the PPT but nothing that onboard batteries can't solve for the short distance required. The Sligo and Wexford lines are unlikely to be electrified so there's no voltage conflict. As for the northern Line, I would say Belfast trains will remain diesel until such a time as a new medium/high speed line is built between Drogheda and Dublin leaving the existing northern line to DARTs only, so effectively 2 separate voltage systems could operate in parallel

CatInABox

I believe that I may have caused some confusion when the tender first came out, by speculating that the Dart expansion had provision for both methods of electrification (1500v DC and 25kV AC), but that was only from reading way too much into one line of the tender. I've seen no evidence since to suggest my speculation was right, and in fact it's the opposite, it really looks like there's only 1500v DC support on the new trains.

The first tranche of the new DARTs are looking like they're bi-mode, but that's Diesel battery and 1500v DC, no AC support at all. This is to allow a bit more flexibility on their usage.

Sorry if I've raised hopes back then, not my intention at all.

No idea if the project will include any provision for AC at all either, i.e. clearances, etc.

River Suir

CatInABox wrote: »

I believe that I may have caused some confusion when the tender first came out, by speculating that the Dart expansion had provision for both methods of electrification (1500v DC and 25kV AC), but that was only from reading way too much into one line of the tender. I've seen no evidence since to suggest my speculation was right, and in fact it's the opposite, it really looks like there's only 1500v DC support on the new trains.

The first tranche of the new DARTs are looking like they're bi-mode, but that's Diesel and 1500v DC, no AC support at all. This is to allow a bit more flexibility on their usage.

Sorry if I've raised hopes back then, not my intention at all.

No idea if the project will include any provision for AC at all either, i.e. clearances, etc.

Unbelievably short sighted unless the long term plan to electrify the whole network would be at 1500v DC?

bk

CatInABox wrote: »

The first tranche of the new DARTs are looking like they're bi-mode, but that's Diesel and 1500v DC, no AC support at all. This is to allow a bit more flexibility on their usage.

I thought the plan was for bi-mode battery and 1500v DC?

Have they scrapped the battery idea and going Diesel instead?

Given that electrification of the intercity lines is 15+ years off, the development of battery tech over that time, might leave for some interesting possibilities.

Cork to Dublin could be 25kV AC, but end before Hazelhatch. Batteries on the intercity train could then power the train from Hazelhatch into Hueston.

There is the idea that with battery tech, you could avoid needing to wire the entire length of lines. Instead you could have sections of wired track, where the train powers up the battery to run on the unwired sections. Can reduce the cost of electrification, in particular avoiding needing to rebuild low bridges or other areas where the electrification would be difficult (areas prone to flooding).

IE 222

bk wrote: »

I thought the plan was for bi-mode battery and 1500v DC?

Have they scrapped the battery idea and going Diesel instead?

Given that electrification of the intercity lines is 15+ years off, the development of battery tech over that time, might leave for some interesting possibilities.

Cork to Dublin could be 25kV AC, but end before Hazelhatch. Batteries on the intercity train could then power the train from Hazelhatch into Hueston.

There is the idea that with battery tech, you could avoid needing to wire the entire length of lines. Instead you could have sections of wired track, where the train powers up the battery to run on the unwired sections. Can reduce the cost of electrification, in particular avoiding needing to rebuild low bridges or other areas where the electrification would be difficult (areas prone to flooding).

It's still battery.

From memory it was planned for only the first batch of units to be dual mode with the rest been electric.

prinzeugen

bk wrote: »

There is the idea that with battery tech, you could avoid needing to wire the entire length of lines. Instead you could have sections of wired track, where the train powers up the battery to run on the unwired sections. Can reduce the cost of electrification, in particular avoiding needing to rebuild low bridges or other areas where the electrification would be difficult (areas prone to flooding).

It looks like that is what is being planned in Scotland for the Perth-Inverness & Edinburgh-Aberdeen lines to overcome supply issues and a big red obstacle that makes raising a pantograph impossible.



Could work here also. Short sections wired to keep the batteries topped up.

L1011

Empire o de Sun wrote: »

If the DART ran on a dedicated network it could have it's own voltage that would be better for an urban system, the Berlin S-bahn is a example I know of (750 V DC). But having two different voltages on a shared network (Dart / suburban / intercity) in the future, will that not add complexity?

Thameslink in london switches from AC to a DC system. I think this is done while the train is stationary in a Farringdon station.

Looking at the map of europe, I see only a few countries use a mix voltage on mainline operations such as France and the UK.

The Wiki map is a decade old and not totally accurate even for then.

Its a fair bit more than just them - Belgium and the Netherlands have 25kV AC on high speed lines and their old native systems (3000V DC/1500V DC) on other lines.

Dual, triple or even quad mode kit has had to exist to cope with this - the old Eurostar could use 750V third rail, 1500V and 3000V DC and 25kV AC; they have dropped the 750V third rail as unneeded now on the new units but added support for the 15kV AC system.

CatInABox

bk wrote: »

I thought the plan was for bi-mode battery and 1500v DC?

Have they scrapped the battery idea and going Diesel instead?

Sorry, it's definitely electric. I'm having a slight mare of a week, where everything that can go wrong, has gone wrong. I looked up the announcement that it was battery and electric, and then posted diesel and electric.

Seriously, in a week or two, I'll look back on this week and find it hilarious, but right now I've got such a fecking ball-ache with everything. Three flat tires on two separate bikes, the key to the garage stopped working, the chain came off the bike twice, the wheel shifted so it was rubbing off the frame (with me thinking that it was just the wind for about 10 minutes). I'm amazed I was late picking one of my kids up only once.

bk

CatInABox wrote: »

Sorry, it's definitely electric. I'm having a slight mare of a week, where everything that can go wrong, has gone wrong. I looked up the announcement that it was battery and electric, and then posted diesel and electric.

No worries at all. We all have those sort of weeks. The missus and I both thought the other was picking up the little one from school today, only realised our mistake just in time!

It feels like half the country is in shock after the kids being back in school this week after so long!!

hope your weekend goes better

DoctorPan

From Peter Smythe and Jim Meade presentations to Engineers Ireland and IRRS.

They are sticking with 1500DC for this round of expansion of wiring to allow the existing stock to be used. Any further expansions will be done at 25kV AC and over time, the DART network could be converted to the AC network once the 8100s, 8500s and 8510s are withdrawn.


Smythe outlined that the new DART stock designed with the average lifespan of 40 years and how the network is expected to change over their lifetime. They are to be 1500 DC and the first batch are to be fitted with batteries as they are expected to be delievered before the wires are extended to Maynooth, Drogheda, Hazelhatch and M3 Parkway so that they enter service immediately as temporary BEMUs for a year or so, once the wiring is complete, they'll be stripped of batteries and enter service as pure EMUs. Smythe said by doing it this way allows Irish Rail to get a new fleet quickly but also creates pressure on the government to prevent the situation of a brand new fleet sitting up in Inchicore unusable as they haevn't invested in wiring the network.

IE 222

DoctorPan wrote: »

From Peter Smythe and Jim Meade presentations to Engineers Ireland and IRRS.

They are sticking with 1500DC for this round of expansion of wiring to allow the existing stock to be used. Any further expansions will be done at 25kV AC and over time, the DART network could be converted to the AC network once the 8100s, 8500s and 8510s are withdrawn.


Smythe outlined that the new DART stock designed with the average lifespan of 40 years and how the network is expected to change over their lifetime. They are to be 1500 DC and the first batch are to be fitted with batteries as they are expected to be delievered before the wires are extended to Maynooth, Drogheda, Hazelhatch and M3 Parkway so that they enter service immediately as temporary BEMUs for a year or so, once the wiring is complete, they'll be stripped of batteries and enter service as pure EMUs. Smythe said by doing it this way allows Irish Rail to get a new fleet quickly but also creates pressure on the government to prevent the situation of a brand new fleet sitting up in Inchicore unusable as they haevn't invested in wiring the network.

Would the battery units not be kept for running services beyond the electrification sections to the likes Kildare, Portlaoise, Dundalk ect. Otherwise they will still require a number of ICRs operating "commuter" services for the sake of a few miles.

L1011

I'm not sure I'd be too happy about taking a BEMU on a cold*, damp** morning with a full load from Maynooth.

Particularly if they only run to Connolly/Pearse/GCD under wires for turnback and its the second run of the day. The plan is to run to Bray under DART+ which would give significantly more charging time.

*batteries perform worse in cold weather, and depending on the battery technology used, they may even need heating to work at peak performance
**higher air conditioning load