MML Electrification: is it going to be completed?

[Technologist]

That sounds about perfect. My only concern here is strain on the batteries would be extremely high, which could cause issues being done multiple times an hour, 16+ hours a day, every day for years.

This would shave a substantial amount of time off journey times, especially on commuter routes, and if timetables can take advantage of this, it's likely to have an actual impact on long term economic growth, as people are brought closer to each other and city centres.

Doesn't negate the need for electrification to enable said train to travel a substantial distance.

It interesting what has happened with battery development, once Lithium Ion types started appearing the most commonly sited design parameter has always been energy density and the endless push to increase it to get 400 miles out of a car instead of 300. However what has actually happened since 2012 (Model S EIS) is that energy density for the best batteries has improved by ~20-30%, cost has decreased by ~10x, lifetime has increased 5X and charge speed has gone up 10x.

Discharging at 6C is right in the middle of an LFP battery's performance envelope and as previously stated because the train we have design is so monstrously overpowered it never need to discharge it batteries for very long in fact we don't even get to a 6C discharge rate on the example I posted until we hit 150mph. LFP types have full discharge lifetime of 5000-10,000 cycles and we are talking about mostly short discharges in the middle of the batteries capacity range, ergo the battery is likely to last many years as a minimum.

The other point to make for the cost argument is that batteries are now so cheap that even if you replaced them yearly the cost per passenger would be pennies on the ticket.

 

[The exile]

It'd be a very expensive way to build an inflexible system. Continuity of OLE is used for power distribution, and you'd either need to provide a lot more infeeds or along-track cables, neither of which would be especially cheap.

Not to mention the fact that the “bits around stations” have a tendency to be the most expensive bits!

 

[Technologist]

It'd be a very expensive way to build an inflexible system. Continuity of OLE is used for power distribution, and you'd either need to provide a lot more infeeds or along-track cables, neither of which would be especially cheap.

The most recent BYD car platform supports peak charge rates of 10C so a battery charges at a rate equivalent to 0-100% in 6 minutes. Obviously this rate cannot be maintained for the entire charging of a battery but non the less a 10-90% charge can be done in 10 minutes. At this rate of charge it is perfectly possible to achieve virtually any current service pattern just with charging in stations alone.

Note that the station charger would have its own very large battery that levels the demand on the local electricity system over the course of a day. Batteries are now so cheap that the biggest cost of battery energy storage is now the gubbins that support them not the batteries themselves.

== Doublepost prevention - post automatically merged: Thursday at 10:37 ==

This is designed out of the electric buses TfL is currently moving to: https://www.london.gov.uk/who-we-ar...l-confusion-designing-out-electric-bus-danger

So I doubt 2.0m/s² acceleration in a train would pass a safety case.

I doubt that they have designed out the lateral acceleration, you can't do much cornering with a g limit of 0.13g!

On the braking front I think there is a good argument to look at using the rail as an eddy current brake, this would allow us to brake vehicles much more rapidly in an emergency in all weathers. This would allow us greatly decrease journey times and allow simpler signalling systems.

 

[Brubulus]

The most recent BYD car platform supports peak charge rates of 10C so a battery charges at a rate equivalent to 0-100% in 6 minutes. Obviously this rate cannot be maintained for the entire charging of a battery but non the less a 10-90% charge can be done in 10 minutes. At this rate of charge it is perfectly possible to achieve virtually any current service pattern just with charging in stations alone.

Note that the station charger would have its own very large battery that levels the demand on the local electricity system over the course of a day. Batteries are now so cheap that the biggest cost of battery energy storage is now the gubbins that support them not the batteries themselves.

== Doublepost prevention - post automatically merged: Thursday at 10:37 ==



I doubt that they have designed out the lateral acceleration, you can't do much cornering with a g limit of 0.13g!

On the braking front I think there is a good argument to look at using the rail as an eddy current brake, this would allow us to brake vehicles much more rapidly in an emergency in all weathers. This would allow us greatly decrease journey times and allow simpler signalling systems.

A train isn't going to be able to do Penzance to Newbury on a single charge. While I do realise the increased acceleration could probably a justify a 10 minute recharge wait at Exeter, without substantially slowing down journeys. I'd rather there was just a few miles of electrification every 60 miles or so, you still need grid feeds for static chargers, if they're going to be charging at 5MW+. Therefore Dore-Meadowhall electrification should be an absolute priority to enable recharging of battery trains.

 

[Killingworth]

A train isn't going to be able to do Penzance to Newbury on a single charge. While I do realise the increased acceleration could probably a justify a 10 minute recharge wait at Exeter, without substantially slowing down journeys. I'd rather there was just a few miles of electrification every 60 miles or so, you still need grid feeds for static chargers, if they're going to be charging at 5MW+. Therefore Dore-Meadowhall electrification should be an absolute priority to enable recharging of battery trains.

Dore-Meadowhall is a section that will be a rather complex electrification project, so very expensive. Just the sort of section where any non wired power source is most economic?

 

[may032]

Dore-Meadowhall is a section that will be a rather complex electrification project, so very expensive. Just the sort of section where any non wired power source is most economic?

True, but it would enable full Sheffield-London OLE running, and battery running between Manchester-Sheffield and Sheffield-Leeds, and others. It’s a key charging point.

 

[Zomboid]

True, but it would enable full Sheffield-London OLE running, and battery running between Manchester-Sheffield and Sheffield-Leeds, and others. It’s a key charging point.

And once you've got the trunk routes wired you don't have to waste energy carrying stored energy about.

Obviously battery tech is improving constantly and it'll be great for losing the requirement to run diesels on increasingly long sections, you do still have to carry several tons of them around if you want to cover any distance away from wires with any kind of performance.

Which is why it's very important IMO to get electrification all the way to Sheffield, so that 810s don't need to burn diesel as a matter of course and their eventual replacement can be pure electric.

The infills to Birmingham, Leeds and Doncaster for the future XC battery bi-modes will ensure that trains present themselves at Birmingham with fully charged reserves and can make the leap from Bromsgrove to Bristol or Severn Tunnel Jn without difficulty. After that we're beyond the realms of anything MML-ish...

 

[Killingworth]

True, but it would enable full Sheffield-London OLE running, and battery running between Manchester-Sheffield and Sheffield-Leeds, and others. It’s a key charging point.

2035-40 at present rate of progress - by which time other technology may make it unnecessary?

 

[InTheEastMids]

Dore-Meadowhall is a section that will be a rather complex electrification project,

I think is making a point that's critical for the economics and operability of discontinuous electrification schemes.

The areas where trains dwell would usually be great for battery charging, but may also be the most costly, complex and disruptive to electrify. Around Sheffield station might be a good example.
If the plan is to use batteries to weasel out of doing difficult bits and focus on areas that are cheap and easy, then in extremis it might be 35 km of electrification along plain line to get a 10 minute charge into a 200 km/h train.

So I agree batteries are game changes, however just focusing on battery technology risks missing the point that in some ways it creates a more complex system where the specifications of train, train service and electrification interact in more complex ways. Cost optimisation of either probably risks creating a more inflexible railway. On a daily basis, that might make service recovery more difficult ("Sorry, your train is late leaving because the inbound service was late and it needed to charge up").

In the longer term, an inflexible system of partially-electrified track, train and timetables might throw up what industry outsiders might describe as "another excuse" as to why the railway cannot respond, or takes years to respond to change. This forum is littered with speculative threads where service enhancements or stock cascades appear unviable due to things like network capacity/existing train path agreements, train leasing arrangements, union agreements, axle loads/speed differentials, route clearance, crew training, platform lengths and power system capacity that can only be solved with significant investment and time. So discontinuous/batterified schemes need some really careful thought to avoid baking in another reason why change just gets too hard for the railway to do. That also points towards starting off with some nice simple ones, rather than leaping into a complex situation of the type that you see around Sheffield.

 

[may032]

2035-40 at present rate of progress - by which time other technology may make it unnecessary?

Possibly. Hopefully GBR brings a level of strategic thinking so they can run the numbers and work out whether Sheffield OLE is needed or not to decarbonise the railway by 2050. I think the 810s can be retrofitted with batteries later on if needed.

 

[InTheEastMids]

I think the 810s can be retrofitted with batteries later on if needed.

Indeed, they might still not have entered service when this gets done.

 

[QSK19]

I think the 810s can be retrofitted with batteries later on if needed.

== Doublepost prevention - post automatically merged: Thursday at 13:22 ==

Indeed, they might still not have entered service when this gets done.

Oh, swapping the engines for batteries before entering service would be the icing on the cake for the farce of the 810 introduction. I may stake a quid on that happening

 

[duffield]

== Doublepost prevention - post automatically merged: Thursday at 13:22 ==


Oh, swapping the engines for batteries before entering service would be the icing on the cake for the farce of the 810 introduction. I may stake a quid on that happening

I realise this is somewhat jocular, but I'd say the reality is that the 810 introduction is approaching the end game, and it's vanishingly unlikely they won't be in full service by the end of 2027 at worst - so before even one more route section of the MML is electrified.

 

[Mikey C]

Possibly. Hopefully GBR brings a level of strategic thinking so they can run the numbers and work out whether Sheffield OLE is needed or not to decarbonise the railway by 2050. I think the 810s can be retrofitted with batteries later on if needed.

Strategic thinking is all very well, but ultimately it all comes down to money. When governments run short of money, long term plans tend to get quickly junked.

 

[GraphitProjekt]

So I agree batteries are game changes, however just focusing on battery technology risks missing the point that in some ways it creates a more complex system where the specifications of train, train service and electrification interact in more complex ways. Cost optimisation of either probably risks creating a more inflexible railway. On a daily basis, that might make service recovery more difficult ("Sorry, your train is late leaving because the inbound service was late and it needed to charge up")

In the longer term, an inflexible system of partially-electrified track, train and timetables might throw up what industry outsiders might describe as "another excuse" as to why the railway cannot respond, or takes years to respond to change.

So discontinuous/batterified schemes need some really careful thought to avoid baking in another reason why change just gets too hard for the railway to do. That also points towards starting off with some nice simple ones, rather than leaping into a complex situation of the type that you see around Sheffield.

Very well said and I couldn't agree more.

While in theory lots of numbers do indeed add up. You can't be running battery trains/discontinuous systems utilising anywhere close to 100% of theoretical capacity. Railway power systems are always designed to support the full service with the loss of one grid connection, and a reduced service (typically lower speed/some cancellations) with two grid connections lost in any given area.

Similarly with battery trains charging from atomised stretches of OLE, you need to be unaffected by missing one of those charges, and still viable missing two. Perhaps more than that is required because we have to account for potential grid connection losses, and faults with the local charging equipment or on train equipment.

In practice this means you want more charging locations than is theoretically necessary and when you combine that with the >100mph line speeds in question (there will need to be some charging in motion going on eventually), the amount of OLE you're able to not build is unlikely to be very impressive - especially weighed against the additional power infrastructure you need to install to support satellite 25kV substations. (It's not going to viable to support all of them off local 33kV DNO infrastructure, just ask the world of DC electrification about that).

It makes more sense to flip the problem the other way round and say "this line will have OLE installed, except for a couple of places where there exceptionally difficult clearances". This is the model of the South Wales metro - but those are branch lines with one type of passenger service making all stops which is quite different than national or inter-regional trunk routes expected to support express, suburban, local and freight services all at once; it's because of freight and express trains that charging in motion will be required which means the amount of OLE not installed is minimal.

Battery/Discontinuous is, however, realistic for minor branch lines with only one service type (or a few very similar ones) with low line speeds/train frequencies and many difficult clearences.

 

[londonmidland]

23:00 and plenty of movements going on in the Leicester-Wigston corridor. Hopefully if electrification happens, it won't be too difficult to amend at a later stage, should the Peterborough to Nuneaton lines be independent of the Midland Mainline.

An image of an Open Train Times signalling map within the Leicester area.

 

[stevieinselby]

The areas where trains dwell would usually be great for battery charging, but may also be the most costly, complex and disruptive to electrify. Around Sheffield station might be a good example.

I'm not an electrical expert, but might it be slightly simplified by the fact that it would be easy to hook up to a fat part of the National Grid if you're in a big town or city centre, rather than needing to add in remote rural substations because there's little power available out there? Also, if you're charging the trains while they are stopped at the station then maybe you only need to electrify the lines at the platforms themselves, meaning no junctions and only short distances, instead of the many miles that you would need if the train was going to be charging while on the move. So yes, the cost per mile of electrification might be a lot more, but if you're only doing a small fraction of the miles then that could offset or negate it.

 

[Zomboid]

There's many ways to approach it, but aside from really big places (London, Birmingham, Glasgow level), the transmission (400 & 275kV) network doesn't really penetrate into the middle of urban areas.

Just doing Sheffield station (as an example) would probably mean connecting to the local 33kV system, which may then need upgrading to handle the load which will be higher than typical traction because it'll be charging to allow trains to run 50+ miles - so much more then the energy typically needed from a normal traction supply. You've also got to find space for the plant, which at 33kV is likely to mean a static frequency converter, and some other switchgear plus ancillaries. So a nice big space with nothing on it that's adjacent to Sheffield station, please.

And then every train will need to be fitted with batteries, and to carry the mass of those batteries around for their entire lives. And come what may they'd need a long enough dwell to charge them up to get to the next charger, so recovering from disruption just got a lot harder.

Batteries are definitely part of the future, but no matter how good they become they should not be (in my opinion) a substitute for properly electrifying trunk routes such as the MML.

 

[GraphitProjekt]

transmission grid infrastructure seems to circle around historic centres of industry and coal generation. (I encourage all to poke around on openinframap) So if you imagine a rough triangle between Birmingham Liverpool and York, there are a lot of 132–400kV lines, similarly in south wales. Sheffield has a lot of underground (probably 1950s era) 275kV cables through the city I think because of the electric arc blast furnaces for the steel mills, Sheffield City 275 is only about a kilometre away from the station. However, none of this means that any of those lines are obviously available to suddenly take on a large railway load - not least one with even more contrasting peaks and troughs then railway loads already are.

Grid infrastructure is more fleeting in areas without heavy industry or continuous urban density, looking at most of South West England and most of the stretch between York and Scotland.
In the long run, a battery majority rail decarbonisation approach would require more generation and transmission infrastructure because of the inherent energy efficiency of going through the middleman of a battery rather than plugging it in directly to the power infrastructure.

None of that is technically infeasible, you can build massive battery capacity at railway substations to even out demand on either side, you can march 400kV transmission lines through sparse countryside (nimbies hate grid infrastructure even more than trains however). But the whole attitude of battery electrification speculation seems to be about "oh no! what if we accidently build a very small amount of OLE that wasn't strictly absolutely necessary when we could have waited a little bit longer for innovations in battery tech to appear". Besides the fact this is the bionic duckweeds argument, there is also something to be said for demanding more finite resources for battery solutions than we really need when other industries have no choice but to use batteries.

I do also want to stress that even though the technologies do exist and the numbers all add up, actually implementing any of the wide scale battery implementations that have been proposed is equivalent to huge amounts of risky innovation in terms of operational procedures, feasibility, maintenance, etc that will balloon in cost and encounter all sorts of pitfalls. The only true battery trains in the UK at the moment is the Greenford branch and the only charging en route is Headbolt Lane and the South Wales metro tram-train. I'm not saying battery tech won't get better, I'm sure it will, but conventional electrification works right now and has been well understood for over 70 years. I think it gets viewed as unfavourable because we know how much it will cost and it's always too much - but there's nothing to suggest that something we've never done before will actually cost any less, this is a rhetoric fallacy that battery train proponents always seem to rely on.

Anyway, if the line in question is the Greenford branch, or Truro to Falmouth, or the Bittern Line - it could have batteries fairly simply. Birmingham-Derby-Sheffield-Leeds is not at all comparable.

 

[Railwaysceptic]

. . . . The only true battery trains in the UK at the moment is the Greenford branch . . . .

At present only as an experiment unavailable to the general public. The existing passenger service is with a good-quality DMU chugging back and forth.

 

[jontyasaurus]

So a nice big space with nothing on it that's adjacent to Sheffield station, please.

Maybe finally a good use for that nice big space with nothing on it that's adjacent to Sheffield station, then?

I agree with you, though; there will be a hell of a lot more infrastructure required in those specific places to enable discontinuous electrification for battery charging vs. full electrification, which effectively spreads the same load out along the line. The question is, I suppose, what the tipping point is for cost-benefit when it comes to electrifying areas such as the area south of Sheffield station.

 

[snalty]

So a nice big space with nothing on it that's adjacent to Sheffield station, please.

This literally does exist, to be fair.

EDIT: Damn, just beaten to it.

 

[Zomboid]

I can see a derelict car park on Google earth, but I don't know that it's big enough for a sufficiently resilient SFC system, and I don't think that's the kind of thing that would get planning permission in a location like that.

Maybe Sheffield wasn't the best example I could have imagined though!

 

[Brubulus]

There's many ways to approach it, but aside from really big places (London, Birmingham, Glasgow level), the transmission (400 & 275kV) network doesn't really penetrate into the middle of urban areas.

Just doing Sheffield station (as an example) would probably mean connecting to the local 33kV system, which may then need upgrading to handle the load which will be higher than typical traction because it'll be charging to allow trains to run 50+ miles - so much more then the energy typically needed from a normal traction supply. You've also got to find space for the plant, which at 33kV is likely to mean a static frequency converter, and some other switchgear plus ancillaries. So a nice big space with nothing on it that's adjacent to Sheffield station, please.

And then every train will need to be fitted with batteries, and to carry the mass of those batteries around for their entire lives. And come what may they'd need a long enough dwell to charge them up to get to the next charger, so recovering from disruption just got a lot harder.

Batteries are definitely part of the future, but no matter how good they become they should not be (in my opinion) a substitute for properly electrifying trunk routes such as the MML.

Just doing Sheffield station is a terrible idea, instead what could be done is the Dore-Meadowhall corridor, to enable trains to charge while moving, increasing flexibility and enabling feeder stations to be in appropriate locations.

 

[Killingworth]

Just doing Sheffield station is a terrible idea, instead what could be done is the Dore-Meadowhall corridor, to enable trains to charge while moving, increasing flexibility and enabling feeder stations to be in appropriate locations.

A good idea until you look at the costed details and the fear that whatever gets done would probably restrict any further improvements for 50 years.

It has to be done in a way that allows for very substantial growth in passenger numbers. 100% at least with modal shift and a growing population.

 

[Nottingham59]

what could be done is the Dore-Meadowhall corridor

Dore-Meadowhall needs doing under any future scenario. Sheffield-Meadowhall is the most intensively used non-electrified route in the country, carrying 11tph. and Dore-Sheffield is close behind with 8tph. See here:

Trivia: What sections of unelectrified line carry the most trains per hour?

Considering lines that are not yet electrified, what sections carry the most trains per hour (tph)? At this stage I'm only considering timetabled passenger services, and not including freight or ECS/NR movements. Or station throats. I can think of the following: Dore - Sheffield (8 tph, I...

www.railforums.co.uk

 

[duffield]

Just doing Sheffield station is a terrible idea, instead what could be done is the Dore-Meadowhall corridor, to enable trains to charge while moving, increasing flexibility and enabling feeder stations to be in appropriate locations.

Once you've done Sheffield station and the track as far as Meadowhall, it's totally bonkers not to wire Meadowhall to Moorthorpe (15 miles) and complete the OHLE on the fast route from Sheffield to Leeds, allowing more services to run as pure EMUs.

Otherwise you're wiring the really expensive complicated bits like Sheffield station and its approaches, but leaving (relatively small) gaps in the more straightforward cheaper sections.

 

[GraphitProjekt]

At present only as an experiment unavailable to the general public. The existing passenger service is with a good-quality DMU chugging back and forth.

Wow didn't know that, nobody ever says that in promotional vids and I haven't been there myself. Having watched a few Jago Hazzard videos I did wonder why he had so few shots of it.

I can see a derelict car park on Google earth, but I don't know that it's big enough for a sufficiently resilient SFC system, and I don't think that's the kind of thing that would get planning permission in a location like that.

Yeah that's like prime land to be some kind of mixed use apartments/retail which is much better idea for it all things considered (transit-orientated development and all that).

I agree with you, though; there will be a hell of a lot more infrastructure required in those specific places to enable discontinuous electrification for battery charging vs. full electrification, which effectively spreads the same load out along the line.

I actually think it's worse than that. Because the power required to run fleets and fleets of battery trains is definitely more than the equivalent electric trains because the middle-step of battery charging/storage. Also the railway load would have even higher peak currents compared to nowadays so the supplying infrastructure has to be built for currents it won't carry most of the time.

The question is, I suppose, what the tipping point is for cost-benefit when it comes to electrifying areas such as the area south of Sheffield station.

The old rule of thumb I used to hear was >100mph or >4tph is where efficiency case for investing in electrification is. Batteries is what we should do with the other side of those thresholds.

 

[Bryson]

I think it would make sense to extend to Meadowhall anyway as this would enable the use of the Wincoback 275kV substation as as supply point. It's right next to the line nextdoor to Meadowhall interchange.

 

[Zomboid]

actually think it's worse than that. Because the power required to run fleets and fleets of battery trains is definitely more than the equivalent electric trains because the middle-step of battery charging/storage

Plus lugging several tons of batteries around everywhere the train goes.