What implications does the latest battery train results have on future UK electrification ?.

[Trainbike46]

I think this once again highlights that it is time to get more BEMUs in service.

We've got some now, both the 756s at TfW and the 777s at Merseyrail. However, we need to get more.

What is really frustrating is when batteries get brought up to justify not electrifying a line, but the BEMUs then don't actually get ordered.

Southern should have been an all (B)EMU operator about 10 years ago, yet there's still no plan to deploy BEMUs on those very simple routes.

 

[BerkshireRails]

Adding batteries to 387s (or replacing them with BEMUs and sending them to Southern) would also allow this, and would also allow the Bedwyn shuttles to be replaced with through electric trains from London.

The 80xs can also take a battery to allow the fasts to go electric.

There is a plan to replace the GWR DMUs (and possibly the 387s) with battery units which can be found in Department for Transport future contracts.

Just because you can put a battery on a train doesn't always make it a good idea.

 

[Sir Felix Pole]

Newbury to Penzance is around 250 miles - a battery powered 802 (or whatever) is not going to make that with a heavily laden service on a wet, cold winter's night with the heating and lighting full on. Surely there is going to have to be some intermediate OLE somewhere - the South Devon banks possibly?

 

[N1]

Newbury to Penzance is around 250 miles - a battery powered 802 (or whatever) is not going to make that with a heavily laden service on a wet, cold winter's night with the heating and lighting full on. Surely there is going to have to be some intermediate OLE somewhere - the South Devon banks possibly?

DB ETA 150s had a range of 400km (in flat areas) at the end of their life in the 80s and 90s. This was with lead acids. Now there was very little auxiliary loads like HVAC, but they also didnt have regen breaking. 250 miles for a modern battery unit is entirely possible.

 

[zwk500]

Newbury to Penzance is around 250 miles - a battery powered 802 (or whatever) is not going to make that with a heavily laden service on a wet, cold winter's night with the heating and lighting full on. Surely there is going to have to be some intermediate OLE somewhere - the South Devon banks possibly?

Yes, there will need to be intermediate OLE. Cogload Jn/Taunton to Exeter is an obvious place due to the higher service levels, extending that through to Newton Abbot or Plymouth would have obvious advantages for power over the most severe gradients.

 

[BerkshireRails]

DB ETA 150s had a range of 400km (in flat areas) at the end of their life in the 80s and 90s. This was with lead acids. Now there was very little auxiliary loads like HVAC, but they also didnt have regen breaking. 250 miles for a modern battery unit is entirely possible.

So then why don't the DB ETA 150s have the record if they have a greater range than the 230s?

Newbury to Penzance is around 250 miles - a battery powered 802 (or whatever) is not going to make that with a heavily laden service on a wet, cold winter's night with the heating and lighting full on. Surely there is going to have to be some intermediate OLE somewhere - the South Devon banks possibly?

I heard on the grapevine that there is a plan to wire Hemidon. Also Newbury to Penzance takes like 5 hours.

 

[InTheEastMids]

Surely there is going to have to be some intermediate OLE somewhere

I have seen a couple of things - maybe from Siemens but perhaps also said by Hendy that makes me think they are exploring provision of the lineside infrastructure and trains within single procurements. I'm using "lineside infrastructure" as the whole point is to be agnostic about whether this is OHL, Vivarail charging points, something else or a mix of technologies.

The basic idea is that GBR sets the service specification and leaves it to the provider to co-optimise lineside infrastructure and train capabilities to deliver the most cost-effective solution between the extreme positions of total route electrification vs minimal charging and massive batteries.

This will obviously be controversial as it looks like it's unwinding nationalisation and poses a number of commercial, operational and regulatory risks that need to be managed.

However it also means that you don't have a situation where GBR is continuously redesigning electrifaction schemes as technical and economic factors change and perhaps more importantly the lineside infrastructure is off GBR's balance sheet and transferred to Opex, which I assume will be more acceptable to HMT. Finally, it (will be claimed that it) <activate Tory Mode> will allow private sector efficiency and discipline to drive down costs and benefit customers in ways that bloated unaccountable public sector organisations can't <Deactivate Tory Mode>. Need to have a lie down now.

 

[WAO]

I'm not impressed with the D78 stock battery stunt. A 200 mile diagram purely on battery when 90% of the route traversed has OLE is nonsense (I imagine GWR couldn't afford a failure off its own metals), as is the costly over-engineering of the unit which is economically beyond a depot's ability to maintain. Presumably Reading has a charger for it. If a modern traction package were necessary then there were Renatus units to be had for scrap value.

There are two roles for battery units; stand alone replacements for lightly used DMU's and as bi-modes where lower speeds, capacity and frequency make OLE extensions less attractive (for now). There is the choice of shore chargers (not cheap), perhaps with batteries themselves as a quick charge requires 10 - 20 times traction current, and from partial provision of OLE (such as OLE to the E Mids with battery operation North). Also of note is Keenor's comment that batteries occupy 13 times the volume of Diesel fuel (its not just weight that counts - they will also require heavy crash-worthy frames).

It's a great pity that the 230 was over-egged as it should really now be going into serial conversion. Equally, Merseyrail's battery 777's seem destined never to venture beyond existing boundaries.

Horses for courses.

WAO

 

[N1]

So then why don't the DB ETA 150s have the record if they have a greater range than the 230s?

They dont have the official record because it was never accurately measured. Bit like City of Truro.

 

[BerkshireRails]

I'm not impressed with the D78 stock battery stunt. A 200 mile diagram purely on battery when 90% of the route traversed has OLE is nonsense (I imagine GWR couldn't afford a failure off its own metals), as is the costly over-engineering of the unit which is economically beyond a depot's ability to maintain. Presumably Reading has a charger for it. If a modern traction package were necessary then there were Renatus units to be had for scrap value.

Reading Depot has a slow charger for the 230.

 

[Peter Sarf]

I guess, given current electrification costs, it will be somewhere in the vicinity of 10-15 trains per hour.

Batteries aren't that expensive compared to electrification these days.
Even a million pounds only gets a few hundred track metres of electrification.

That is quite high - suburban networks usually.

I'm going to disagree with the consensus here. I don't see that electrifying Didcot to Oxford makes much sense.

Yes, it would be lovely to have an all electric network, but the costs are just astronomical, so a good cold hard look at the different options needs to be considered. Transpenine electrification makes a lot of sense - a relatively short and very busy diesel line between two large electrified networks at each end, so for a (relatively) low cost you can replace several fleets of diesels with all electric trains (perhaps with batteries for extensions to Hull etc)

But Oxford isn't like that. Almost all trains to Oxford continue on somewhere else. So as lots of people on this thread say, why not electrify Didcot to Oxford to Birmingham NS, via Solihull and Coventry. The problem is, as far as I can see, thst still only allows the Didcot - Oxford stoppers to go fully electric. All other trains would still need to be bi-mode! Manchester - Bournemouth would also need Reading - Basingstoke to be wired, whilst North East to Reading needs MML to be finished and Birmingham to Derby to be done. GWR long distance trains generally carry on towards Worcester (OK, there are a few Banburys that would be fully electric).

Most of the low hanging fruit of electrification that allows huge numbers of trains on fully contained diagrams to be replaced for short lengths of wiring has already been done. Battery tech seems to me to be ideal for places like Oxford, where it could reconnect the stoppers at didcot and remove all that pollution from the air just as well as a billion pounds of wiring.

We should then concentrate on where electrification genuinely is the only option. For me discontinuous electrification on the Chiltern mainline would be a far bigger priority than Oxford, coupled with batter technology - wire the cheap bits from Marylebone to High Wycombe and the Snow Hill core, and with decent batteries you could replace every Chiltern and West Midland Snow Hill train with BEMUs.

Oxford is a better/more-obvious stopping point than Didcot. The costs are not unusually high - it has not been done because Oxford remodelling has paused it. It allows more electric only trains to London instead of a change at Didcot - temporary change wasn't it ?. It allows more time for charging of trains that go beyond to Worcester. It would allow some electrification beyond Oxford onto the Worcester route.

It is obvious to me that electrifying more of the suburban networks should come first. In the case above. the Snow Hill lines out to Stratford and Leamington (?). And the other way to Stourbridge. Any Leamington-Stratford service might well get enough charge on the Birmingham bound bits at each end to allow a battery to cover Hatton to Wilmcote.

The problem will be costs, electrification isn't cheap, but neither is new rolling stock, unless your already ordering new stock to replace older stock, that is at end of its useful life,

In that case, and if its across numerous operators, and a large order, economies of scale could make new stock, with battery provision, cost effective over electrification schemes, where the vehicles can operate either as electric, with battery for non powered sections, then, clearly, there would be advantages, as one type of unit, could replace more than one other type

One possible option could be to use the interchangeable traction pack concept, used on the 230, to enable units to be changed from electric, to deisel, and battery, using self contained modules, so a depot can be standardised on one type of unit, but those units could be a range of types some overhead/ battery, some 3rd rail/ Battery, and even some Deisel powering electric traction units,,

I am erring on the side of all units having enough battery to make then useful. Either as backup or for actual use.

As batteries keep getting cheaper, it will make sense for most trains to have a battery that can at the very least get a train to limp to a station or keep the HVAC going. The basic systems supported on battery today, for such a short time, seems very outdated when there's technology out there to add resilience.

And replacing diesel tanks for batteries seems like a good way to keep old DMUs in service in the future, assuming they remain structurally sound and are on suitable routes that includes facilities to recharge quickly.

Given I can't see the Government (either Labour today or whoever gets in next) rushing to invest in sorting out all the non-electrified routes anytime soon, batteries help with 'net zero' targets - as well as making older trains cleaner and quieter.

I would say all but the longest non-electrified routes would be candidates for EMUs that are mainly battery with just one diesel engine as a get out of jail card (probably so little used that it fails on start up !).

The issue with talking about batteries for Didcot to Oxford is that we're not looking at replacing a diesel fleet with battery bi-modes.
The IETs that run the Oxford fasts and Cotswolds services are diesel bi-modes and have another 30 years in service, so unless the diesel generators can be swapped out for battery packs that would be sufficient to run Didcot to Hereford and back or they can be swapped out to other services, those trains will still be running on diesel for some/all of the route.
The Oxford to Didcot shuttles really want to be re-joined to the London to Didcot services that are run by 387s – if those were switched out for battery bi-modes then yes, there would be a small number of 165s that could be binned, but there would be a lot more 387s that have many years of life left in them that would become surplus to requirements and that would only be sensible if they could be redeployed elsewhere.

Well electrify enough to make batteries feasible. But if conversion is a no-no then cascade the Bi-Mode IETS to Cross Country.

All we need to do is plan a national strategy of electrification allowing for the right cascades at the right time. By the time these GWR to Cross Country hand me down IETs (diesel+electric) need replacing the battery technology may well have progressed to the stage where a lot less electrification of the gaps need to happen (gaps like Bromsgrove to Bristol or more severely Plymouth to Penzance).

Given the success of this trial (which to me seems like quite a successful stunt), and how battery technology has developed over the past decade, it seems quite reasonable to forsee regular BEMUs with 2-300 mile ranges being available within a decade. Allied to that could be BE Frieght Locos with a 200 mile range. The challenge at that point will be providing enough power to the stretches of line that are to be used for charging. But if that is overcome - and it would have to be overcome for a fully electrified infrastructure also - then that will cover the vast majority of the railway, with exceptions for high speed / high bolume routes (which tyoically already have the wires up).


It does surprise me how there is a decent proportion of opinions that can’t seem to understand (accept?) the rather considerable benefits battery units.

Leaving aside the very considerable cost saving, there is a big improvement in system reliability - not just from the absence of electrification infrastructure failures but also from all types of incident that require the power to be off, from tresspass to severe weather to engineering works and plenty in between.

It would also, usually, be quicker to deliver electric servcies with BEMUs than when electrifying the infrastructure.

So, BEMUs could offer significantly cheaper and more reliable electric services, delivered sooner, with much lower ongoing operation and maintenance cost than an electrified infrastructure.

What‘s not to like?

I would see getting as much of a route electrified as is easily possible thus leaving very manageable gaps that a battery fitted train can easily get through. Once we have trains with enough battery capacity to do more than just limp somewhere convenient in the event of a power failure then longer gaps with decent lengths of electrification in between, to allow charging, would be doable. I think we are getting to that stage.

My simple arithmetic would be that if a battery train has a conservative range of X miles then each electrification island needs to be a bit more than X miles in length. Then factor in the power demands on the electrified bits doubling (to cover charging). If doubling is too much for the OLE then, for example, dropping to 150% would mean 2X miles electrified for every X miles non electrified. Over time as services become more intense then more of the gaps need filling in or the OLE beefing up.

Newbury to Penzance is around 250 miles - a battery powered 802 (or whatever) is not going to make that with a heavily laden service on a wet, cold winter's night with the heating and lighting full on. Surely there is going to have to be some intermediate OLE somewhere - the South Devon banks possibly?

I would electrify the Devon banks (Exeter to Plymouth) to help. Maybe not continuous but do the more demanding bits (demanding for a train) and leave the hard to electrifiy bits.

 

[BerkshireRails]

Oxford is a better/more-obvious stopping point than Didcot. The costs are not unusually high - it has not been done because Oxford remodelling has paused it. It allows more electric only trains to London instead of a change at Didcot - temporary change wasn't it ?. It allows more time for charging of trains that go beyond to Worcester. It would allow some electrification beyond Oxford onto the Worcester route.

The plan was the wires would have run as far as Hanborough which is station past Oxford on the North Cotsworld Line.

 

[HSTEd]

Newbury to Penzance is around 250 miles - a battery powered 802 (or whatever) is not going to make that with a heavily laden service on a wet, cold winter's night with the heating and lighting full on. Surely there is going to have to be some intermediate OLE somewhere - the South Devon banks possibly?

It takes twenty minutes to cover the ten route kilometres between Plymouth Laira and Saltash, much of which is single track.

That's an obvious charging location in my view, even if the Royal Albert bridge is annoying.

 

[Annetts key]

This.

It's the future (that's not hyperbolic IMO). It solves many issues, and makes it easier to 'upgrade' old lines to get rid of diesel, as well as potentially making it easier and cheaper to build new lines in the future. Imagine the many long decommissioned lines that could be brought back into service without the need for electrification.

Ironically, this isn't like ICE vs EV where many people are arguing for keeping fossil fuel powered vehicles. Here it seems to be overhead or third-rail vs battery, and comments I've seen about how the grid won't be able to cope. Well, the electricity to charge the batteries is the same electricity that would power the trains via wires. There are obviously losses when you convert from AC to DC and back etc, and losses along the line, so I wonder what the actual differences are.

You potentially don't have to worry about a section of railway where you can only run so many trains at once, and you can store battery storage systems at a station/depot more slowly - to dump into a battery fast when the time comes if needed (or slow charge them when stabled). So that can save a lot of infrastructure upgrade works too.

The reasons people will not like it are likely the same reasons people attack EVs. They believe the grid cannot cope (it can and will) and the batteries will only last a few years (they'll last way longer). I suppose there's also the fire risk concern, but that will depend on the battery chemistry - as well as batteries rarely just catching fire for no reason.

Alas, the laws of physics means you can't have everything. You can't have your cake with cream filling and hundreds and thousands and a cherry on top and eat it, sorry, it doesn't work like that in the real world. There is and never will be a battery that can be maximised with all these factors. You have to have some compromises. So the compromises with a battery (made up of one or more cells) include considering:

• Electrical storage capacity
• Physical size
• Lifespan
• Maximum charging rate
• Maximum discharging rate
• Maximum permitted discharge level (deep cycle)
• Maximum permitted recharge level (for some battery types)
• Battery chemistry type
• Losses due to temperature

For example, a battery designed for fast charging or fast discharging typically will have a lower capacity compared to a battery designed for maximum capacity but not designed for fast charging/discharging.

And also the lifespan will be less if the battery is fast charged and/or deep cycled (run to a low charge level regularly).

Lifespan is a very important factor. Although the costs of some types of batteries are falling, this will not continue forever. And depending on how batteries are used and the type (including chemistry), they may only last for five to ten years. So replacement battery costs has to be included in any calculations for whole life operation, maintenance and installation costs.

Every time you convert from one type of energy to another there are losses. So if you convert from AC electrical power to charge a battery, there are losses. If you then use the energy to convert back to electricity to charge another battery, there are two more sets of losses. Then when you use the second battery to power a train, there are further losses.

The fire risk is manageable. The issue with cells or batteries catching fire is either overcharging due to a poor design of charging system, poor quality of the cell or battery or physical damage.

Please note that I am in favour of new trains being provided with a battery so that they can run beyond the wires / third rail.

But just chucking battery powered trains onto the network is not going to work everywhere. IMHO there needs to be some careful thought about additional provision of OHLE for some parts of some lines so that trains can recharge while on the move. And/or OHLE or some other method of recharging for trains that are stationary at stations / depots.

And it is beneficial for high speed lines to be fitted with OHLE for the high speed sections. And for lines on steep or long inclines or where acceleration is continuous for a while (pulling away from stations) to be fitted with OHLE for a reasonable distance.

I have seen a couple of things - maybe from Siemens but perhaps also said by Hendy that makes me think they are exploring provision of the lineside infrastructure and trains within single procurements. I'm using "lineside infrastructure" as the whole point is to be agnostic about whether this is OHL, Vivarail charging points, something else or a mix of technologies.

The basic idea is that GBR sets the service specification and leaves it to the provider to co-optimise lineside infrastructure and train capabilities to deliver the most cost-effective solution between the extreme positions of total route electrification vs minimal charging and massive batteries.

This will obviously be controversial as it looks like it's unwinding nationalisation and poses a number of commercial, operational and regulatory risks that need to be managed.

However it also means that you don't have a situation where GBR is continuously redesigning electrifaction schemes as technical and economic factors change and perhaps more importantly the lineside infrastructure is off GBR's balance sheet and transferred to Opex, which I assume will be more acceptable to HMT. Finally, it (will be claimed that it) <activate Tory Mode> will allow private sector efficiency and discipline to drive down costs and benefit customers in ways that bloated unaccountable public sector organisations can't <Deactivate Tory Mode>. Need to have a lie down now.

Government borrowing costs less than PFI schemes or commercial borrowing. And commercial schemes are not always cost-effective solutions in the long term. Once you have awarded a contract, you will typically be locked in to that supplier and that contract. Then "private sector efficiency" disappears...

 

[Bald Rick]

The reasons people will not like it are likely the same reasons people attack EVs.

I disagree. In both cases it is driven largely by not fully understanding the benefits / costs / risks, with a small percentage of vested interests driving the narrative. In EV world that vested interest is the oil companies, and to a lesser extent some parts of the automotive industry. In Rail electrification world, it is the electrification supply chain and to a smaller extent the fleet engineering people, some of whom really love fixing diesel trains.

What is really frustrating is when batteries get brought up to justify not electrifying a line, but the BEMUs then don't actually get ordered.

That I agree with.

 

[BerkshireRails]

It takes twenty minutes to cover the ten route kilometres between Plymouth Laira and Saltash, much of which is single track.

That's an obvious charging location in my view, even if the Royal Albert bridge is annoying.

You can also recharge the every other hour Gunnislake Branch service, which should be made hourly by a new loop to increase justification for wiring Plymouth to St Budeaux at a minimum.

 

[Bald Rick]

Government borrowing costs less than PFI schemes or commercial borrowing.

Whilst that is generally true, it’s less so now. The rate for 30 year UK Gilts (Government Bonds) is currently 5.6%. There’s not that much commercial borrowing available over that timescale, as the banks tend to hedge on shorter term, but typcially it is now in the 5-6% range.

I can also borrow from Nationwide for 10 years at 4.4%. Which means I am a lower risk to lenders than the UK Government. Which I must day is concerning.

(The UK is in a precarious position on debt by internatonal comparison).

 

[SynthD]

The challenge at that point will be providing enough power to the stretches of line that are to be used for charging. But if that is overcome - and it would have to be overcome for a fully electrified infrastructure also

Is the difficulty in making a connection from the track to the grid, and the capacity of that connection? While full electrification demands a beefy connection every, say, 60km, batteries can tolerate adapting to the cheaper places to connect with smaller draw from the grid, even if they are further than 60km apart.

I'm not impressed with the D78 stock battery stunt. A 200 mile diagram purely on battery when 90% of the route traversed has OLE is nonsense (I imagine GWR couldn't afford a failure off its own metals), as is the costly over-engineering of the unit

That train can’t collect from OLE. What is the over engineering, and what does that tell us about the trains passengers will use?

 

[WAO]

That train can’t collect from OLE. What is the over engineering, and what does that tell us about the trains passengers will use?

It would have made the point better had it worked to say, Worcester and back - a useful journey and about the same distance.

For "over-engineering" you'll have to consult more widely. It had new bogies, traction package, a loo, etc. OTT. Why isn't the type now on the IoW?

 

[AndrewE]

It would have made the point better had it worked to say, Worcester and back - a useful journey and about the same distance.

but if it went kaput it's miles away from home with no chance of rescue and potentially blocking a single line!

For "over-engineering" you'll have to consult more widely. It had new bogies, traction package, a loo, etc.

I would think that if you were going to do a battery trial it would only be sensible to give it current spec running gear, rather than handicap it from the start.

 

[JohnRegular]

I'm not impressed with the D78 stock battery stunt. A 200 mile diagram purely on battery when 90% of the route traversed has OLE is nonsense (I imagine GWR couldn't afford a failure off its own metals), as is the costly over-engineering of the unit which is economically beyond a depot's ability to maintain.

Since this unit is just a trial, does any of this matter? Can you explain why it is less impressive because the route has OLE which isn't used by the train?

 

[stevieinselby]

Ironically, this isn't like ICE vs EV where many people are arguing for keeping fossil fuel powered vehicles. Here it seems to be overhead or third-rail vs battery, and comments I've seen about how the grid won't be able to cope. Well, the electricity to charge the batteries is the same electricity that would power the trains via wires. There are obviously losses when you convert from AC to DC and back etc, and losses along the line, so I wonder what the actual differences are.

One factor that is different is the rate at which power is drawn. When trains are running off OHLE, there will be a fairly steady power draw throughout the day – but when they are running on batteries and then recharging, that demand will be more spiky. The Greenford branch system of having a static trickle-charged battery that can then fast charge the train battery works well on a single branch like that, but I don't have enough knowledge of electrical systems to know how scalable that would be, or whether the spiky demand is even an issue. The physics could be quite different for a route like the North Downs line, where trains could recharge on the move between unelectrified sections, and the completely unelectrified lines like the Greenford branch, where trains can only recharge while stopped at designated stations.

I'm not impressed with the D78 stock battery stunt. A 200 mile diagram purely on battery when 90% of the route traversed has OLE is nonsense (I imagine GWR couldn't afford a failure off its own metals), as is the costly over-engineering of the unit which is economically beyond a depot's ability to maintain. Presumably Reading has a charger for it. If a modern traction package were necessary then there were Renatus units to be had for scrap value.

It was a proof of concept, that's all. Obviously no-one thinks that that means that a class 230 can now achieve over 200 miles on a single charge in normal revenue-earning service, any more than they think GWR are proposing to use class 230s on services from Paddington to Oxford. The fact that that particular line has OHLE for much of the route is irrelevant, it was a convenient test bed that they could use on this occasion, and by arranging the run as they did, (a) they could get as near as dammit to 200 miles, which is a nice round number to use as the target, and (2) the double-run at the end meant that if the batteries were not performing as well as hoped, they wouldn't end up with the train stranded a hundred miles away.

You can also recharge the every other hour Gunnislake Branch service, which should be made hourly by a new loop to increase justification for wiring Plymouth to St Budeaux at a minimum.

Running an hourly service to Gunnislake is a waste of resources. The line sees an average of 25 passengers per train journey, there is nowhere near enough demand or potential to justify an increase in frequency, it would be money down the drain.

 

[CdBrux]

. Well, the electricity to charge the batteries is the same electricity that would power the trains via wires. There are obviously losses when you convert from AC to DC and back etc, and losses along the line, so I wonder what the actual differences are.

You potentially don't have to worry about a section of railway where you can only run so many trains at once, and you can store battery storage systems at a station/depot more slowly - to dump into a battery fast when the time comes if needed (or slow charge them when stabled). So that can save a lot of infrastructure upgrade works too.

and what's more you are far more likely to be able to fill the batteries on much cheaper (overnight) energy

 

[vuzzeho]

I would love to see (probably a pipe dream) something like a 180 or 221 be converted to battery operation. Yes, there are the Scottish 222s but I think that's still just a plan right now. But a 180 could make for a decent testbed, and batteries would probably improve its reliability. That said, I feel like there's a reason this couldn't happen - I just don't know what.

 

[zwk500]

I would love to see (probably a pipe dream) something like a 180 or 221 be converted to battery operation. Yes, there are the Scottish 222s but I think that's still just a plan right now. But a 180 could make for a decent testbed, and batteries would probably improve its reliability. That said, I feel like there's a reason this couldn't happen - I just don't know what.

The Class 180 uses hydraulic transmission, so it's not a case of just plugging in batteries, but you'll need a completely new 'something' between the batteries and the Hydraulic transmission to drive the unit. Or rip out the entire traction system and replace it with an electric transmission system.
Class 220, 221 and 222 are Diesel-Electric units so in theory the batteries could be connected to the electric drive system but I expect the level of engineering required is going to be cost-prohibitive when alternatives are available readily on the market. There are plenty of routes that are going to be beyond the range of batteries for the remaining 20-25 years of service life the Voyagers have. There was a proposal many years ago that tried to turn a voyager into a bi-mode with a pantograph (Project Thor). I don't know if it was tried and failed, or if the DfT simply didn't even bother: https://publications.parliament.uk/pa/cm201011/cmselect/cmtran/writev/economy/te89.htm

Converting older EMUs to BEMUs is something that could be looked at, but I think DMUs will just need to be steadily cascaded away from the B/EMU routes until withdrawal.

 

[The exile]

The issue with talking about batteries for Didcot to Oxford is that we're not looking at replacing a diesel fleet with battery bi-modes.
The IETs that run the Oxford fasts and Cotswolds services are diesel bi-modes and have another 30 years in service, so unless the diesel generators can be swapped out for battery packs that would be sufficient to run Didcot to Hereford and back or they can be swapped out to other services, those trains will still be running on diesel for some/all of the route.
The Oxford to Didcot shuttles really want to be re-joined to the London to Didcot services that are run by 387s – if those were switched out for battery bi-modes then yes, there would be a small number of 165s that could be binned, but there would be a lot more 387s that have many years of life left in them that would become surplus to requirements and that would only be sensible if they could be redeployed elsewhere.

That’s assuming there’s nowhere else those trains can be redeployed/ cascaded to.

 

[JamesT]

The Class 180 uses hydraulic transmission, so it's not a case of just plugging in batteries, but you'll need a completely new 'something' between the batteries and the Hydraulic transmission to drive the unit. Or rip out the entire traction system and replace it with an electric transmission system.
Class 220, 221 and 222 are Diesel-Electric units so in theory the batteries could be connected to the electric drive system but I expect the level of engineering required is going to be cost-prohibitive when alternatives are available readily on the market. There are plenty of routes that are going to be beyond the range of batteries for the remaining 20-25 years of service life the Voyagers have. There was a proposal many years ago that tried to turn a voyager into a bi-mode with a pantograph (Project Thor). I don't know if it was tried and failed, or if the DfT simply didn't even bother: https://publications.parliament.uk/pa/cm201011/cmselect/cmtran/writev/economy/te89.htm

Converting older EMUs to BEMUs is something that could be looked at, but I think DMUs will just need to be steadily cascaded away from the B/EMU routes until withdrawal.

The problem with the 22x is although they use electric motors, there's no bus between the carriages. Project Thor proposed adding a new build coach with a pantograph, but that would only have been available to propel that carriage. No funding from government was forthcoming so it never got off the paper stage.
There has been one attempt to convert a DMU into a hybrid, a Chiltern 165. You may be able to find details of it under the name 'HyDrive'. It did run in service, but I believe has since been converted back to its original configuration and Chiltern are now looking for replacement units which says a lot about how well that went.

 

[jon0844]

and what's more you are far more likely to be able to fill the batteries on much cheaper (overnight) energy

I think Network Rail buys energy at a fixed rate for some period of time, but even if that's the case, it could still help the grid if charging was done at specific off-peak/low-demand time periods. GB Railways could in theory work with GB Energy to make best use, and if they wanted to go one step further, using V2G style tech, the train could even provide backup power back to the grid or local facilities.. but I think I might be getting a little carried away now in terms of what can be done and what likely will be done.

== Doublepost prevention - post automatically merged: 22 Aug 2025 ==

Older EMUs to BEMUs is something that could be looked at, but I think DMUs will just need to be steadily cascaded away from the B/EMU routes until withdrawal.

Even if you didn't upgrade any existing trains, having this for all new builds going forward would still make a huge difference in the years ahead. Depending on how GB Railways wants to do things, imagine the huge order for new battery trains (possibly with OHLE/third rail capabilities too) across the country to replace all those ageing DMUs.

Chances are you'll be looking at more lines getting signalling upgrades, so that's another reason why some older trains may just be better off going for scrap.

 

[WAO]

Since this unit is just a trial, does any of this matter? Can you explain why it is less impressive because the route has OLE which isn't used by the train?

....because it's a physical trial - a prototype, not a computer model - that's why a potential route would also be important (yes I know it had Greenford). It also needed to be of modest engineering innovation, both to reduce risk and because of the limited resources of Vivirail/GWR. If it were a Hitachi or Siemens trial, with their very deep and willing R&D pockets, free of UK accountants, well that would be different. Just a deep clean and new moquette would have done.

WAO

 

[stevieinselby]

That’s assuming there’s nowhere else those trains can be redeployed/ cascaded to.

Hence why I wrote "that would only be sensible if they could be redeployed elsewhere"