Future of the GWR electrification

[Benjwri]

Wasn’t the platform work at Bath more to do with flattening out the curve so that the IETs would fit without passengers having to do the long jump to board them?

Yes it was to increase platform capacity and reduce stepping distance. The work that had to be done for electrification was to move platform canopies back to ensure sufficient clearance.

 

[GRALISTAIR]

Should also be looking at getting electric freight to Mendip stone trains, and the big Gravity battery manufacturing plant (near Bridgewater), as part of sequencing where to extend to.

To me that is a biggie followed of course by rolling programme for rest of B&H to Taunton.

 

[The exile]

Yes it was to increase platform capacity and reduce stepping distance. The work that had to be done for electrification was to move platform canopies back to ensure sufficient clearance.

Sure the platform canopies are as before. They are further back from the edge - but that’s because the edge is further forward.

 

[Hellzapoppin]

Iirc the canopies needed to be cut back to allow clearance for the ole but as that wasn't allowed the platforms had to be extended instead.

 

[Nottingham59]

Should also be looking at getting electric freight to Mendip stone trains,

Electrifying Mendip stone trains should be achieved with bi-mode freight locomotives like the Class 99.

 

[swt_passenger]

Iirc the canopies needed to be cut back to allow clearance for the ole but as that wasn't allowed the platforms had to be extended instead.

There’s a Rail Engineer article from 2017 that explains the reasoning, and also highlights that moving the tracks nearer each other allowed for single OHLE masts in the 6 foot. But they do also point out the better stepping distances achieved.

Fortunately, there is a very generous gap between the two tracks that pass through the station, so it was decided to exploit this space, increasing the width of Platform 1 to Bristol by up to 1.2 metres and the Up platform to London by up to 1.8 metres. This solution not only added capacity to the station platforms to reduce overcrowding in the face of growing passenger numbers, but also meant it will be possible to place single stanchions down the middle of the realigned tracks in the future. As a result, when it comes to electrification through Bath Spa, the platform canopies can remain untouched.

Modernisation of Bath Spa station - Rail Engineer

Listen to this article It’s an exciting time for the rail industry. Network Rail has recently embarked on a £50 billion Railway Upgrade Plan across the national network, designed to address, not only the significant increase in demand that exists today, but also what is projected for the future...

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[Snow1964]

Electrifying Mendip stone trains should be achieved with bi-mode freight locomotives like the Class 99.

But if going to double head them, as some trains are, then need decent electricity supply too. These sort of locos are 6Mw (about 8000HP). Even if not normally operated in multiple still need line to avoid restricting how many electric trains can pass.

The good news is there is a huge National Grid switch station at Beanacre (near Melksham) and cables linking it to one at Bramley (near Reading) are being upgraded (including moving about 4 miles underground near Devizes). So getting big power to the area is fairly easy.

 

[The exile]

There’s a Rail Engineer article from 2017 that explains the reasoning, and also highlights that moving the tracks nearer each other allowed for single OHLE masts in the 6 foot. But they do also point out the better stepping distances achieved.

Reading that article it seems fairly clear that it was flattening the curves and increasing platform capacity were the drivers, while making sure that it was compatible with future OHLE.

 

[Nottingham59]

if going to double head them, as some trains are,

I can imagine that you might need two Class 66s on a 4000t stone train (2 x 2.4 kMW), but a single Class 99 on electric can deliver more than that. The main unelectrified uphill gradient seems to be from Melksham to Thingley Junction, which is not a mainline. And the Berks and Hants seems relatively benign gradient-wise.

So I'd be surprised if they ever need to double up a Class 99.

 

[The exile]

I can imagine that you might need two Class 66s on a 4000t stone train (2 x 2.4kW), but a single Class 99 on electric can deliver more than that. The main unelectrified uphill gradient seems to be from Melksham to Thingley Junction, which is not a mainline. And the Berks and Hants seems relatively benign gradient-wise.

So I'd be surprised if they ever need to double up a Class 99.

Melksham - Thingley might not be a main line, but occupancy times on single track sections can often be critical. I’m assuming, though, that your suggestion of 99s is dependent on electrification of all but the “last mile”.

 

[Nottingham59]

Melksham - Thingley might not be a main line, but occupancy times on single track sections can often be critical. I’m assuming, though, that your suggestion of 99s is dependent on electrification of all but the “last mile”.

Not really. As far as I can see, most of the heavy stone trains from the Mendips run downhill. They don't need a lot of energy, so the benefits of electifying right up to the quarries would be minimal.

Electric operation will be most useful where the increased power (6MW on electric vs 1.6MW on diesel) will allow greater acceleration, short track occupation times, and therefore less conflict with passenger trains on busy sections of line. And these tend to be the lines that are already electrified.

 

[Elecman]

But if going to double head them, as some trains are, then need decent electricity supply too. These sort of locos are 6Kw (about 8000HP). Even if not normally operated in multiple still need line to avoid restricting how many electric trains can pass.

The good news is there is a huge National Grid switch station at Beanacre (near Melksham) and cables linking it to one at Bramley (near Reading) are being upgraded (including moving about 4 miles underground near Devizes). So getting big power to the area is fairly easy.

I think you mean 6MW not 6KW

 

[59CosG95]

But if going to double head them, as some trains are, then need decent electricity supply too. These sort of locos are 6Mw (about 8000HP). Even if not normally operated in multiple still need line to avoid restricting how many electric trains can pass.

The good news is there is a huge National Grid switch station at Beanacre (near Melksham) and cables linking it to one at Bramley (near Reading) are being upgraded (including moving about 4 miles underground near Devizes). So getting big power to the area is fairly easy.

Isn't it also the case that said National Grid substation at Melksham/Beanacre is the main feeding point for Thingley Jn ATFS? IIRC that was commissioned, and Thingley provides 25kV in a trough route eastwards toward Chippenham, connecting to the ±25kV at Christian Malford ATS.

 

[stuving]

Isn't it also the case that said National Grid substation at Melksham/Beanacre is the main feeding point for Thingley Jn ATFS? IIRC that was commissioned, and Thingley provides 25kV in a trough route eastwards toward Chippenham, connecting to the ±25kV at Christian Malford ATS.

Yes it is.

 

[jayah]

One of the oddities of GWR electrification is when it was stopped, ended up with some of the busier parts not being done, but some of lighter used parts completed. Eg Bathampton-Bristol sees 5 or 6 trains each way per hour, but Swindon-Chippenham only about 2 per hour each way.

Then GWR ended up with wrong mix of trains, and now has bi-modes on fully electrified Paddington-Cardiff services, and trains that can't use electric running as not bi-modes on electrified section.

Yes they have the 387s, but these are pure electric, not BEMUs so can't get to Oxford or Bedwyn etc, so forced to use long distance stock on these shortish services. Meanwhile plenty of 3+ hour services are run with former suburban DMUs

Really need better coordination of electrification extension with sourcing of appropriate rolling stock, and of course an opportunity exists as the DMU fleet will need replacing over next 4-8 years.

Should also be looking at getting electric freight to Mendip stone trains, and the big Gravity battery manufacturing plant (near Bridgewater), as part of sequencing where to extend to.

The DMU fleet needs replacing long before these routes are going to be electrified. GWR services from London to Cardiff were never meant to be operated by outer suburban EMUs with no First Class. A full fleet of BiModes was the only sensible choice, even if Swansea, Oxford and Bristol Temple Meads had been electrified.

 

[brad465]

Electrifying Mendip stone trains should be achieved with bi-mode freight locomotives like the Class 99.

Does anyone actually know how long the Mendip quarries have left in terms of operating life? If they're near the end of their life by the time electrification reaches at least Westbury (which in reality seems a long way off), then electrifying the two branches to Whatley and Merehead/Torr probably won't be worth it. Of course other freight opportunities in the region may well come up, but not necessarily utilising the same routes.

 

[stuu]

Hanson have applied for permission to extract 2m tons per year from a site with expected reserves of 160m tons. So trains are likely to be needed for quite a while

 

[YorkshireBear]

Hanson have applied for permission to extract 2m tons per year from a site with expected reserves of 160m tons. So trains are likely to be needed for quite a while

I believe the peaks have similarly long term reserves and permissions so at least those two large aggregate flows could definitely warrant long term infrastructure investment.

 

[brad465]

Hanson have applied for permission to extract 2m tons per year from a site with expected reserves of 160m tons. So trains are likely to be needed for quite a while

What year was that application made?

 

[The exile]

What year was that application made?

Not long enough ago to affect the timescale of electrification if there were 80 years worth of reserves.

 

[stuu]

What year was that application made?

2023

 

[HSTEd]

2 million tonnes per year is only around ~6000 tonnes per day.

Can we really make the needle move on an electrification business case with two aggregate trains per day?

 

[Trainbike46]

2 million tonnes per year is only around ~6000 tonnes per day.

Can we really make the needle move on an electrification business case with two aggregate trains per day?

that depends, but electric freight trains accellerate better and are faster up hills, so electrifying those few trains a day may well be the cheapest way to increase capacity on some lines

 

[GRALISTAIR]

And every little bit helps!

 

[stuu]

2 million tonnes per year is only around ~6000 tonnes per day.

Can we really make the needle move on an electrification business case with two aggregate trains per day?

That's one quarry, there's at least 5 active sites. Today there have been 13 eastbound trains so far, some of them overnight

 

[Western Sunset]

Re-Mendip stone trains. I basically see two options if electrification proceeds westwards:

1. Electric to Westbury, then diesel to Whatley/Merehead
2. Bimode direct to quarry - no way the electrify with OHL to Whatley, in particular

As noted above, the link through Melksham is a key component in electrification.

 

[Sly Old Fox]

Re-Mendip stone trains. I basically see two options if electrification proceeds westwards:

1. Electric to Westbury, then diesel to Whatley/Merehead
2. Bimode direct to quarry - no way the electrify with OHL to Whatley, in particular

As noted above, the link through Melksham is a key component in electrification.

Ideally the line through Melksham would be redoubled, but I can’t see anyone paying for it anytime soon. But if it is electrified I’d hope it would be done a way that means it could be redoubled easily in the future.

 

[eisenach]

I believe the peaks have similarly long term reserves and permissions so at least those two large aggregate flows could definitely warrant long term infrastructure investment.

Are Peaks coming back ? Great !

 

[Snow1964]

How many freight trains per day is the Gravity battery plant expected to generate? Is their likely destination already wired? (TIA)

Not sure, but the Certificate of compliance was announced yesterday with Agratas and build partner Sir Robert MacAlpine expecting 200 lorry movements per day during build phase of building one.

The whole thing will cost £4bn, and expect to create 4000 jobs when fully built in about 6 years, and make 40Gw/h of batteries annually (enough for about 500,000 electric vehicles annually).

So at least 1000 tons of raw materials and 1000 tons of valuable batteries eg day. There are also other businesses on the site including big distribution hubs so could have dozens of containers needing moving every day.

Not sure what rail freight sector's appetite for getting potential business is, but could be few trains per day. The Somerset part of M5 is notorious for delays and closures due to accidents which in theory could help rail.

 

[zwk500]

So at least 1000 tons of raw materials and 1000 tons of valuable batteries eg day. There are also other businesses on the site including big distribution hubs so could have dozens of containers needing moving every day.

That's a decent loading for a train a day (or maybe 4 trains in 5 days), so I suspect people will be interested but will depend on where the other ends of the flows are and what paths are available.