Future of the GWR electrification

[Hellzapoppin]

The Henbury line wasn't re signalled as part of the BASRE project so that work will eat into any funding. Would it be a separate project ?

 

[Zomboid]

I'm all for it in principle, but which services would be able to change modes if Filton bank is electrified? I won't hold my breath for any of the local branches in the Bristol area just yet.

 

[Bald Rick]

Are any other countries using ‘discontinuous electrification’?

It is very telling that I haven’t heard of any.

France, Germany, Italy, Ireland, Finland all have, or plan to use BEMUS with part of their routes electrified.

 

[Benjwri]

I'm all for it in principle, but which services would be able to change modes if Filton bank is electrified? I won't hold my breath for any of the local branches in the Bristol area just yet.

Yes I agree with this. I’m assuming they aren’t planning to wire Temple Meads, so the benefits will be limited, especially until they replace the current fleet. The money could be put to so much better use on some of the appalling transport links elsewhere in the West of England.

 

[zwk500]

I'm all for it in principle, but which services would be able to change modes if Filton bank is electrified? I won't hold my breath for any of the local branches in the Bristol area just yet.

The WECA funding that was announced a while ago for studies was for electrification of Filton Bank with BEMUs on the Severn Beach line.

 

[Snow1964]

France, Germany, Italy, Ireland, Finland all have, or plan to use BEMUS with part of their routes electrified.

Are they actually using discontinuous electrification (unelectrified gaps on a main line), or simply using BEMUs to operate on non-electrified branches.

There is a difference between operating an extension beyond the wires, and switching between wires and batteries multiple times on same main route

 

[Trainbike46]

I'm all for it in principle, but which services would be able to change modes if Filton bank is electrified? I won't hold my breath for any of the local branches in the Bristol area just yet.

GWR is in need of a big new fleet for local/regional/branch services, and the churchward procurement does talk about BEMUs. That would suggest the trains on the local services around Bristol would go to BEMU.

Yes I agree with this. I’m assuming they aren’t planning to wire Temple Meads, so the benefits will be limited, especially until they replace the current fleet. The money could be put to so much better use on some of the appalling transport links elsewhere in the West of England.

Why would you assume that they wouldn't wire Temple Meads? If you're doing the Filton Bank, it would be insane to not include Temple Meads station in that.

Are they actually using discontinuous electrification (unelectrified gaps on a main line), or simply using BEMUs to operate on non-electrified branches.

And what is the difference between those two operationally?

In Ireland at least, it includes operation of BEMUs on unelectrified parts of the Dublin-Belfast mainline

 

[Zomboid]

GWR is in need of a big new fleet for local/regional/branch services, and the churchward procurement does talk about BEMUs. That would suggest the trains on the local services around Bristol would go to BEMU

It would make sense to include BEMUs if they have enough wiring on the routes they'd run. The current service on the Avonmouth line seems to be Avonmouth to Weston and Severn Beach to Temple Meads, I suspect that for reliable BEMU operations that'd need a larger proportion of the route wired than just Stapleton Road to Temple Meads, but the branch itself looks pretty awkward with many bridges and tunnels.

Maybe a adding a shortish section around Avonmouth would be enough to keep the batteries topped up.

I don't know where the other end would be, but the North Filton line would have a decent proportion wired so probably wouldn't need anything more to support BEMUs, unless the idea is to get power to Avonmouth by going that way.

 

[InTheEastMids]

Are they actually using discontinuous electrification (unelectrified gaps on a main line), or simply using BEMUs to operate on non-electrified branches.

The term discontinuous electrification is getting chucked around to mean everything from having avoiding doing a few meters under a bridge through to un-electrified branch lines and perhaps some future cross-country scheme where a battery is used across tens of miles between two points with existing electrification. Not a criticism of anybody here, but I wonder if we need some more precise language about this, especially given the impacts on train specifications.

Why would you assume that they wouldn't wire Temple Meads? If you're doing the Filton Bank, it would be insane to not include Temple Meads station in that.

I really hope so. It feels very mid-twentieth century to stand on busy, un-electrified stations like Temple Meads, with the death-rattle and fug of 1980s/90s DMU all around.
That being said, I guess from a deliverability perspective is perhaps the best place to start is a more straightforward, linear scheme of extension to existing electrification. If I was holding the purse strings, I wouldn't want a new electrification team cutting its teeth on Temple Meads, as this would strike me as one of the most complex locations in the South West.

 

[Snow1964]

It would make sense to include BEMUs if they have enough wiring on the routes they'd run. The current service on the Avonmouth line seems to be Avonmouth to Weston and Severn Beach to BTM, I suspect that for reliable BEMU operations that'd need a larger proportion of the route wired than just Stapleton Road to BTM, but the branch itself looks pretty awkward with many bridges and tunnels.

Maybe a adding a shortish section around Avonmouth would be enough to keep the batteries topped up.

I don't know where the other end would be, but the North Filton line would have a decent proportion wired so probably wouldn't need anything more to support BEMUs, unless the idea is to get power to Avonmouth by going that way.

It is not smart operationally to have the wires stop at low speed junctions, where junction isn't at a station. Much safer to have the changeover point a few hundred metres along the branch. The simple reason is add a potential failure risk at critical point (across the junction, or on the busy section).

Sometimes better to extend wires to a station (if first station is not far along branch), so changeover is stationary. But in general, when trains accelerate away from junctions, the acceleration area is not ideal place for changeover. For trains leaving branches, they might get checked by junction signals or need to slow for the junction, so better to change whilst coasting or slowing towards a junction, not once on the mainline, and trying to accelerate.

 

[Zomboid]

It is not smart operationally to have the wires stop at low speed junctions, where junction isn't at a station. Much safer to have the changeover point a few hundred metres along the branch. The simple reason is add a potential failure risk at critical point (across the junction, or on the busy section).

Sometimes better to extend wires to a station (if first station is not far along branch), so changeover is stationary. But in general, when trains accelerate away from junctions, the acceleration area is not ideal place for changeover. For trains leaving branches, they might get checked by junction signals or need to slow for the junction, so better to change whilst coasting or slowing towards a junction, not once on the mainline, and trying to accelerate.

In the case of Severn Beach line, the first stop (Montpelier) is under 3 bridges and through a tunnel. It might be that those won't be any kind of a challenge to electrify, I've no idea.

The junction is 500m from the end of the platform at Stapleton Road though, so chances are that'll be the changeover location if BEMUs do run on the branch.

 

[zwk500]

It is not smart operationally to have the wires stop at low speed junctions, where junction isn't at a station. Much safer to have the changeover point a few hundred metres along the branch. The simple reason is add a potential failure risk at critical point (across the junction, or on the busy section).

The obvious thing to do is to have the Narroways Hill Jn to Montpelier Tunnel (exclusive) wired, but between Montpelier Tunnel and Clifton Down Tunnel (inclusive of both) is unlikely to be wired at least in the short term. This means the 3 stations of Montpelier, Redland and Clifton Down would be unwired. If the Henbury Loop is wired, then that could be extend towards Sea Mills to reduce the required Battery length.

what is the difference between those two operationally?

Discontinuous electrification requires at least two sections of full OLE where the trains run as EMUs with a section(s) in between operated using on-board Batteries. Using BEMUs on non-electrified branches implies that at one end there is full OLE, but at the other there is either nothing, an alternative charging option, or simple OLE sufficient for static charging only.

For an example of a system using both, Midland Metro trams operates as a BEMU extension on a non-electrified line to Wolverhampton Station (ORM shows this section as wired, but it doesn't appear to be from photos), but as discontinuous electrification for the section across Victoria and Centenary Squares (ORM correctly shows this section as unelectrified). Trams charge from the OLE during service.

Most proposals for discontinuous electrification envisage that all or most of the fleet would need to be BEMUs, whereas battery extensions on a branch line would not necessarily need more than a small proportion of the fleet suitably equipped (although you might well do for flexibility anyway).

In Ireland at least, it includes operation of BEMUs on unelectrified parts of the Dublin-Belfast mainline

This is Battery Extension on non-electrified lines, not discontinuous electrification as conventionally proposed. The OLE is proposed to be extended out from Dublin in a contiguous fashion (at least until it gets to wherever the proposed limit of 1.5KV DC/25KV AC is planned to be).

 

[Annetts key]

The Henbury line wasn't re signalled as part of the BASRE project so that work will eat into any funding. Would it be a separate project ?

Incorrect. Half of the line between Hallen Marsh junction and Filton West junction was controlled previously by Bristol Panel. That part (along with the lines making up all the chord lines and the cross lines between Patchway junction, Stoke Gifford junction, Filton junction and Filton West junction) were resignalled when transferred to control by TVSC. This is all axle counter and SSI type signalling.

The remaining section towards (and beyond) Hallen Marsh junction was resignalled in 1993. It's SSI and conventional DC (AC immune) double rail track circuits and controlled by St. Andrews junction signal box.

Some work would likely be needed to get it electrification ready, but not complete resignalling, assuming any OLE stops at Henbury (or it doesn't go that far).

 

[Wyrleybart]

Why would you assume that they wouldn't wire Temple Meads? If you're doing the Filton Bank, it would be insane to not include Temple Meads station in that.
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I thought the stumbling block with erecting OLE under Temple Meads was Brunel's magnificent overall station, and hanging span wires across it. BR obviously managed it at some other rather splendid stations but the Western has always been different hasn't it. Example "A" Bath. l suspect NR gave up because they hadn't got the will to fight the avonshire residents, and I really cannot see that ever resolved personally.

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[John R]

No, the government pulled the plug because it was fed up at the spiralling cost of electrification. It wasn’t Network Rail’s decision.

 

[Annetts key]

I thought the stumbling block with erecting OLE under Temple Meads was Brunel's magnificent overall station, and hanging span wires across it. BR obviously managed it at some other rather splendid stations but the Western has always been different hasn't it. Example "A" Bath. l suspect NR gave up because they hadn't got the will to fight the avonshire residents, and I really cannot see that ever resolved personally.

The part of BTM station currently used by trains was not built by Brunel...

Bath Spa platforms have already been built outwards ready for the OLE. By widening the platforms, there is now enough (or should be) clearance between any OLE and the station canopy.

 

[The exile]

I thought the stumbling block with erecting OLE under Temple Meads was Brunel's magnificent overall station, and hanging span wires across it. BR obviously managed it at some other rather splendid stations but the Western has always been different hasn't it. Example "A" Bath. l suspect NR gave up because they hadn't got the will to fight the avonshire residents, and I really cannot see that ever resolved personally.

Solutions had been proposed (and, IIRC accepted) for the section through Bath, as they were for the Royal Border Bridge and other historic structures elsewhere. The scheme simply ran out of money and resuming the electrification for bi-mode London trains alone makes little sense. The need to de-carbonise and de-pollute the local services (and to replace the rolling stock) will be the driver here.

The part of BTM station currently used by trains was not built by Brunel...

Bath Spa platforms have already been built outwards ready for the OLE. By widening the platforms, there is now enough (or should be) clearance between any OLD and the station canopy.

The Bath issue is the visual impact of structures, not physical clearances.

 

[Last Hurrah]

Is it correct that wiring runs have to done in multiples of either 750m or 1500m ?

I ask this question as it was given in answer why wires stop short of the boundary marker between TfW infrastructure for the CVL and infrastructure previously overseen by NR

 

[Zomboid]

Is it correct that wiring runs have to done in multiples of either 750m or 1500m ?

I ask this question as it was given in answer why wires stop short of the boundary marker between TfW infrastructure for the CVL and infrastructure previously overseen by NR

They don't have to or you'd see all kinds of silliness at buffer stops and junctions which had the cheek to be not a multiple of that from another fixed point, but it's probably a convenient length based on how much cable there is on a drum.

 

[Snow1964]

Today's Government announcement has only partly clarified the £800m for West of England

£150m to improve rail infrastructure across the region, including funding to support WECA’s ambitions for increased frequency of services between Brabazon and the city centre. £200m for Mass transit development between Bristol, Bath, South Gloucestershire and North Somerset.

Doesn't say how the other £450m is allocated, just checked WECA website and nothing there, so at moment there appears to be £450m towards some unidentified improvements

Biggest ever investment in city region local transport as Chancellor vows the 'Renewal of Britain'

Working people in cities and towns from Sunderland to Solihull will benefit from the biggest investment in regional transport, as every part of the country prospers under Plan for Change.

www.gov.uk

 

[Trainbike46]

I thought the stumbling block with erecting OLE under Temple Meads was Brunel's magnificent overall station, and hanging span wires across it. BR obviously managed it at some other rather splendid stations but the Western has always been different hasn't it. Example "A" Bath. l suspect NR gave up because they hadn't got the will to fight the avonshire residents, and I really cannot see that ever resolved personally.

No, the government pulled the plug because it was fed up at the spiralling cost of electrification. It wasn’t Network Rail’s decision.

Exactly, the GWEP was curtailed because the government felt it was too expensive, not because of any other reason, and certainly not because of heritage reasons.

Solutions had been proposed (and, IIRC accepted) for the section through Bath, as they were for the Royal Border Bridge and other historic structures elsewhere. The scheme simply ran out of money and resuming the electrification for bi-mode London trains alone makes little sense. The need to de-carbonise and de-pollute the local services (and to replace the rolling stock) will be the driver here.


The Bath issue is the visual impact of structures, not physical clearances.

As you state yourself that was resolved.

 

[Benjwri]

Today's Government announcement has only partly clarified the £800m for West of England



Doesn't say how the other £450m is allocated, just checked WECA website and nothing there, so at moment there appears to be £450m towards some unidentified improvements

Biggest ever investment in city region local transport as Chancellor vows the 'Renewal of Britain'

Working people in cities and towns from Sunderland to Solihull will benefit from the biggest investment in regional transport, as every part of the country prospers under Plan for Change.

www.gov.uk

It’s expected Helen Goodwin will clarify later today on specific plans for WECA’s allocation of the money I understand.

 

[Mikey C]

As many trains start from Bristol TM, having wires there will be essential for charging battery trains while they are waiting there.

 

[brad465]

I thought the stumbling block with erecting OLE under Temple Meads was Brunel's magnificent overall station, and hanging span wires across it. BR obviously managed it at some other rather splendid stations but the Western has always been different hasn't it. Example "A" Bath. l suspect NR gave up because they hadn't got the will to fight the avonshire residents, and I really cannot see that ever resolved personally.

The eastern station approaches also underwent a major remodelling 4 years ago that would have led to duplicated electrification work if wires went up before this date. The remodelling also made the approach "OHLE ready", some putting the wires up will not be as problematic as if they started from scratch.

 

[Annetts key]

Half of the line between Hallen Marsh junction and Filton West junction was controlled previously by Bristol Panel. That part (along with the lines making up all the chord lines and the cross lines between Patchway junction, Stoke Gifford junction, Filton junction and Filton West junction) were resignalled when transferred to control by TVSC. This is all axle counter and SSI type signalling.

The remaining section towards (and beyond) Hallen Marsh junction was resignalled in 1993. It's SSI and conventional DC (AC immune) double rail track circuits and controlled by St. Andrews junction signal box.

Some work would likely be needed to get it electrification ready, but not complete resignalling, assuming any OLE stops at Henbury (or it doesn't go that far).

Some more details:

BASRE provided for OLE immunisation to just west of the former BAC aircraft crossing (113½ miles). This is where new IRJs (IBJs) were provided for traction immunisation purposes.

However, the new signalling continued to 115¼ miles on the down line approximately (this being St. Andrews junction first down line signal).

The first TVSC controlled signal on the up line is at 116 miles approximately.

The site of the former Henbury station is at approximately 115m 34 chains. The proposed site of the new station is in a new location.

 

[Snow1964]

The site of the former Henbury station is at approximately 115m 34 chains. The proposed site of the new station is in a new location.

The new station is a single platform serving a (reversing) siding on north side of the line, no platforms on through lines. So is only for terminating trains from the east. If it wasn't parallel to the Avonmouth lines could be seen as located on a very short branch line.

 

[brad465]

The new station is a single platform serving a (reversing) siding on north side of the line, no platforms on through lines. So is only for terminating trains from the east. If it wasn't parallel to the Avonmouth lines could be seen as located on a very short branch line.

Is there a particular reason why having a through service to Avonmouth via Henbury isn't being considered (unless it is and I've missed it)? It wouldn't be much further and could form a "rounder" service by merging with the existing Avonmouth terminators.

 

[The exile]

Is there a particular reason why having a through service to Avonmouth via Henbury isn't being considered (unless it is and I've missed it)? It wouldn't be much further and could form a "rounder" service by merging with the existing Avonmouth terminators.

Something to do with a level crossing at the Avonmouth end ISTR. (Dick entrance?)

 

[Annetts key]

Something to do with a level crossing at the Avonmouth end ISTR. (Dick entrance?)

There are no level crossings that I can think of between Henbury and St. Andrews Road station (which is the first station when travelling towards Avonmouth in that direction. The line between Henbury and Hallen Marsh junction is mostly on an embankment or in a cutting. Hence the roads / accommodation accesses are either over bridges or underbridges.

 

[zwk500]

There are no level crossings that I can think of between Henbury and St. Andrews Road station (which is the first station when travelling towards Avonmouth in that direction. The line between Henbury and Hallen Marsh junction is mostly on an embankment or in a cutting. Hence the roads / accommodation accesses are either over bridges or underbridges.

No but King Road is single line just south of St Andrews Road and Gloucester Road level crossing is immediately north of Avonmouth station, and you'd run at least to Avonmouth as it has the extra tph that starts/terminates there. Is there signalling to turn back to the north from Avonmouth?