Has electrification had its day?

[jayah]

Moderator note: Split from https://www.railforums.co.uk/threads/cuts-to-investment-in-rail-infrastructure.211931

Dad's was saying that one long before I was born!

The problems is that often people don't like the costs they suggest which tend to be far far closer actual outturns.

== Doublepost prevention - post automatically merged: 5 Dec 2020 ==


The problem is that in specifying very high performance bi-modes for the MML you now struggle to achieve any journey time savings with electrification.

Interesting that buying high performance modern trains rather than outdated low performance ones that are outrun by 40yr old HSTs is now a problem...

If batteries and bimodes can match the journey times, perhaps electrification has had its day.

 

[Domh245]

If batteries and bimodes can match the journey times, perhaps electrification has had its day.

That all depends on how much value you assign to 1kg of CO2e emissions in the business case

 

[Ianno87]

That all depends on how much value you assign to 1kg of CO2e emissions in the business case

Possibly an argument for assigning a higher such value in de-carboning urban areas than say, remote rural Scotland. Then that lends itself to a strategy of electrification extensions with bi-modes for more rural areas.

 

[Domh245]

Possibly an argument for assigning a higher such value in de-carboning urban areas than say, remote rural Scotland. Then that lends itself to a strategy of electrification extensions with bi-modes for more rural areas.

Carbon is an issue wherever it's emitted as it eventually works it's way into the atmosphere, but that would be a preferable strategy for reducing the other pollutants from diesels (NOx, PM, etc) - however the flip side is that those other pollutants are controlled to varying degrees by the exhaust 'scrubbing' equipment onboard modern trains - particulate filters and selective catalytic reduction (adblue) etc. Replacing something like the new CAF DMUs with a bi-mode will only see small improvements in air quality in cities, the main benefit would be the carbon reduction

 

[hwl]

Carbon is an issue wherever it's emitted as it eventually works it's way into the atmosphere, but that would be a preferable strategy for reducing the other pollutants from diesels (NOx, PM, etc) - however the flip side is that those other pollutants are controlled to varying degrees by the exhaust 'scrubbing' equipment onboard modern trains - particulate filters and selective catalytic reduction (adblue) etc. Replacing something like the new CAF DMUs with a bi-mode will only see small improvements in air quality in cities, the main benefit would be the carbon reduction

1. SCR doesn't work at low exhaust temperatures
2. DOC units oxidise all the NO to the more problematic NO2.
3. The C1 drive cycles used for the EuroIIIB/V engines doesn't adequately replicate real rail drive cycles, (the older F cycle was more realistic) so many of the reductions in engine emissions were due to swapping to an easier drive cycle not real reductions in real operating conditions.

Hence plenty of benefits from urban electrification.

PS the 195 don't even have a DPF as the DOC was enough to get them to pass IIIB, 196s do.

== Doublepost prevention - post automatically merged: 21 Dec 2020 ==

Moderator note: Split from https://www.railforums.co.uk/threads/cuts-to-investment-in-rail-infrastructure.211931

Interesting that buying high performance modern trains rather than outdated low performance ones that are outrun by 40yr old HSTs is now a problem...

If batteries and bimodes can match the journey times, perhaps electrification has had its day.

How to you recharge batteries given the short range and how to you decarbonise the bi-modes long term?

 

[Domh245]

1. SCR doesn't work at low exhaust temperatures
2. DOC units oxidise all the NO to the more problematic NO2.
3. The C1 drive cycles used for the EuroIIIB/V engines doesn't adequately replicate real rail drive cycles, (the older F cycle was more realistic) so many of the reductions in engine emissions were due to swapping to an easier drive cycle not real reductions in real operating conditions.

Hence plenty of benefits from urban electrification.

PS the 195 don't even have a DPF as the DOC was enough to get them to pass IIIB, 196s do.

Fair point about the SCR and DOCs not necessarily performing as hoped, although this does sound like poor implementation rather than a fundamental flaw - indeed I was under the impression from some of the research I'd done that a NOx optimised DOC was useful for improving SCR performance. The point about unrealistic drive cycles is disappointing to see, although real-world performance tests of some modern units would be interesting to see. The improvement over sprinters and turbostars would be interesting, as would the potential further improvement from not running the diesels at all

I don't disagree that there are plenty of benefits from urban electrification, but I would think that the universal CO2 reductions would be the 'driving' benefit than the air quality improvements in cities, which is more of a convenient side effect. Indeed, I would think that electrifying cities would tend to have the better business case anyway by merit of more services which can then become zero emission at point of use (higher benefit for similar cost)

 

[Purple Orange]

Has electrification had it’s day? No. It’s only just getting started. I can’t emphasise the importance of electrifying our rail network AND completing our transition to clean energy supplies. Batteries have they own problems regarding production & disposal that are not as prevalent with electric trams & trains.

 

[hwl]

Fair point about the SCR and DOCs not necessarily performing as hoped, although this does sound like poor implementation rather than a fundamental flaw - indeed I was under the impression from some of the research I'd done that a NOx optimised DOC was useful for improving SCR performance.

It is fairly fundamental. SCR only works above a threshold temperature. (When the engine is working hard)
NOx optimsed DOC is indeed key to optimising SCR but if the temperature is too low for SCR then you have produced more NO2 in the exhaust than if you had done nothing! As TfL about bus emissions but don't expect an answer! There is a reason they went battery hybrid in a big hurry... SCR not working was increasing NO2 levels in places.

Another solution for NOx is EGR to sort out the low power / exhaust temperature issues and potential fuel injection into the exhaust system to raise the temperature which is bad for decarbonisation or go for hybrid battery power.

Europe decided they would go for just one NOx reduction measure, the US on the other hand saw major flaws in an SCR only approach so it has largely ended up as and EGR +SCR approach in the states for NOx reduction.

The problem is that big high profile intercity electrification scheme have tended to be popular with those signing things off.

 

[Philip Phlopp]

No.

We already know diesel traction is to be phased out - indeed, with bans on diesel engined road vehicles and changes coming in the HGV space, it's difficult to see whether there will be suitable diesel engines available in future years, even if the demand was there.

Everything else goes down the route of electric traction anyway - whether it's OLE, third rail, battery or hydrogen (fuel cells charge batteries, which turn traction motors) so the cost of putting a coat hanger on the roof of a train and one of Taunton's small electrical substations under the floor is small and the challenge one of the least arduous in the rail industry (especially as all of your battery and hydrogen trains start life as electric designs, normally 25kV AC designs, into which battery packs or fuel cells are connected along the same electrical bus as the pantograph+transformer unit).

What will happen (and is already starting to happen) is that a TOC would like an IPEMU/BEMU to operate, say, a 20km route. Then they see further route options and diagram savings and want bigger batteries, then costs get too much and the outcome is 'well, couldn't we electrify 10km of the route' and you basically have rolling electrification by stealth. It might be the best we can hope for, but a few km at a time is still a few km more than nothing.

 

[43096]

Has electrification had it’s day? No. It’s only just getting started. I can’t emphasise the importance of electrifying our rail network AND completing our transition to clean energy supplies. Batteries have they own problems regarding production & disposal that are not as prevalent with electric trams & trains.

Not to mention using batteries means lugging the things round with you the whole time, which either uses more energy or affects performance.

 

[Domh245]

Europe decided they would go for just one NOx reduction measure, the US on the other hand saw major flaws in an SCR only approach so it has largely ended up as and EGR +SCR approach in the states for NOx reduction.

Thanks for the post. That line is interesting - I take it then that most European rail engines don't have EGR then? That's surprising as most diesel road vehicles have had it for a while now

What will happen (and is already starting to happen) is that a TOC would like an IPEMU/BEMU to operate, say, a 20km route. Then they see further route options and diagram savings and want bigger batteries, then costs get too much and the outcome is 'well, couldn't we electrify 10km of the route' and you basically have rolling electrification by stealth.

That's certainly preferable to what happens with potential EV purchases, where people decide not to purchase a BEV because of the two or three journeys a year they make that are beyond the cars range and then just get a plug-in or other ICE vehicle!

 

[hwl]

Thanks for the post. That line is interesting - I take it then that most European rail engines don't have EGR then? That's surprising as most diesel road vehicles have had it for a while now

None have EGR in the UK And I can't think of any on the continent of the top of my head.

== Doublepost prevention - post automatically merged: 21 Dec 2020 ==

No.

We already know diesel traction is to be phased out - indeed, with bans on diesel engined road vehicles and changes coming in the HGV space, it's difficult to see whether there will be suitable diesel engines available in future years, even if the demand was there.

Everything else goes down the route of electric traction anyway - whether it's OLE, third rail, battery or hydrogen (fuel cells charge batteries, which turn traction motors) so the cost of putting a coat hanger on the roof of a train and one of Taunton's small electrical substations under the floor is small and the challenge one of the least arduous in the rail industry (especially as all of your battery and hydrogen trains start life as electric designs, normally 25kV AC designs, into which battery packs or fuel cells are connected along the same electrical bus as the pantograph+transformer unit).

What will happen (and is already starting to happen) is that a TOC would like an IPEMU/BEMU to operate, say, a 20km route. Then they see further route options and diagram savings and want bigger batteries, then costs get too much and the outcome is 'well, couldn't we electrify 10km of the route' and you basically have rolling electrification by stealth. It might be the best we can hope for, but a few km at a time is still a few km more than nothing.

Much like I see it. Those "10km" I could quite often see being on higher traffic routes in urban area to begin with. Aligning with end of exiting stock life will also play a part in timing.
The problems for battery are places like Windermere branch where there is virtually no distance /time under the wiring to charge up hence needing a few km to make things work.

 

[Bletchleyite]

Definitely not. Batteries, while the best option for road traffic and possibly small branch lines[1], do have environmental issues that OHLE doesn't.

[1] For genuine branch lines I'd go more down a light rail line - DC OHLE, light rail style vehicles (e.g. the high floor Metrolink trams, but in some cases low-floor may make sense), track brakes so level crossings can stay open safely, level boarding etc.

 

[Irascible]

Surely it's easier to scrub emissions at a powerplant than on a moving vehicle? constant temperature, fairly constant rate of emissions, all the space you need, etc. My somewhat uninformed guess would be that carrying "empty" batteries around is not really a problem on a public transport vehicle. You can harvest just as well via OHLE as with local batteries too ( and don't have to carry them around! ).

[1] For genuine branch lines I'd go more down a light rail line - DC OHLE, light rail style vehicles (e.g. the high floor Metrolink trams, but in some cases low-floor may make sense), track brakes so level crossings can stay open safely, level boarding etc.

Maybe another attempt at a railbus ( I'm sure there was a thread about one recently ) rather than a tram - don't want to have to rebuild too much infrastructure. Might get a bit awkward if you want to share one end of a route with full heavy rail.

Has anyone done a study on induction coil charging a rail vehicle? I can just imagine S&T engineers having heart attacks, but it's being tested out on ( under! ) roads so it's not entirely theoretical & you wouldn't have to wire the whole route.

 

[Bletchleyite]

Maybe another attempt at a railbus ( I'm sure there was a thread about one recently ) rather than a tram - don't want to have to rebuild too much infrastructure. Might get a bit awkward if you want to share one end of a route with full heavy rail.

A tram-train vehicle basically is that, I suppose.

Has anyone done a study on induction coil charging a rail vehicle? I can just imagine S&T engineers having heart attacks, but it's being tested out on ( under! ) roads & you wouldn't have to wire the whole route.

It certainly worked fine for buses on the route 7 trial in MK. Not sure how much point there is for rail - a pantograph and short length of OHLE (even if low voltage OHLE rather than 25kV, though given that branch line origin stations will increasingly have 25kV OHLE anyway, e.g. all the Thames Valley branches do, that's probably easier) would do the job fine and doesn't present the same issues as that does on roads. Or even third rail where that is present on the mainline (e.g. for Uckfield, Burscough Bridge or Kirkby-Skem/Wigan).

 

[Irascible]

It certainly worked fine for buses on the route 7 trial in MK. Not sure how much point there is for rail - a pantograph and short length of OHLE (even if low voltage OHLE rather than 25kV, though given that branch line origin stations will increasingly have 25kV OHLE anyway, e.g. all the Thames Valley branches do, that's probably easier) would do the job fine and doesn't present the same issues as that does on roads. Or even third rail where that is present on the mainline (e.g. for Uckfield, Burscough Bridge or Kirkby-Skem/Wigan).

My only thought was that you wouldn't have to keep raising & lowering the pan - but then if you really wanted you could automate that anyway. I suppose the electrical gear isn't actually that much different for either.

 

[Bletchleyite]

My only thought was that you wouldn't have to keep raising & lowering the pan - but then if you really wanted you could automate that anyway. I suppose the electrical gear isn't actually that much different for either.

Induction doesn't transmit power over any considerable distance, so you need to drop an induction grid onto the road surface anyway (this is how it worked on the MK bus trial), so either way there's something to automate or press a button for. So you might as well stick to existing railway technology rather than create something new.

 

[Philip Phlopp]

My only thought was that you wouldn't have to keep raising & lowering the pan - but then if you really wanted you could automate that anyway. I suppose the electrical gear isn't actually that much different for either.

APCO already in use for IEP.

Charging is fun though - all the electric you need for an hour of use, transferred into the battery pack in 5 minutes. Spot any problems with that ?

 

[Bletchleyite]

Charging is fun though - all the electric you need for an hour of use, transferred into the battery pack in 5 minutes. Spot any problems with that ?

No, given that electric buses are already doing that. (Well, maybe not 5 minutes, but certainly 15 or so).

I would expect that the amount of electricity needed to move a lightweight EMU at say 50mph for an hour is about the same as that needed to move something like a Pendolino at 125 or a large freight train for 15 minutes anyway, and that comes in on the same type of OHLE and pantograph.

 

[Philip Phlopp]

No, given that electric buses are already doing that. (Well, maybe not 5 minutes, but certainly 15 or so).

I would expect that the amount of electricity needed to move a lightweight EMU at say 50mph for an hour is about the same as that needed to move something like a Pendolino at 125 or a large freight train for 15 minutes anyway, and that comes in on the same type of OHLE and pantograph.

Try again...

 

[Irascible]

Induction doesn't transmit power over any considerable distance, so you need to drop an induction grid onto the road surface anyway (this is how it worked on the MK bus trial), so either way there's something to automate or press a button for. So you might as well stick to existing railway technology rather than create something new.

There's been a bunch of trials in Korea with induction loops over whole routes, iirc. Not really sure how much switching is necessary - Over coil, charge... not over coil, no charge.

APCO already in use for IEP.

Charging is fun though - all the electric you need for an hour of use, transferred into the battery pack in 5 minutes. Spot any problems with that ?

I'm sure every rural terminus will cope fine! just like replacing petrol stations with fast charging stations is a simple way forwards.

( and because I get taken seriously too often, "Yes, one or two" ).

 

[Bletchleyite]

Try again...

Perhaps you might be a little more helpful and give us some figures, then?

 

[Philip Phlopp]

There's been a bunch of trials in Korea with induction loops over whole routes, iirc. Not really sure how much switching is necessary, it's the same mechanism as harvesting which happens in motion all the time.



I'm sure every rural terminus will cope fine! just like replacing petrol stations with fast charging stations is a simple way forwards.

( and because I get taken seriously too often, "Yes, one or two" ).

It's not entirely clear how the electrical demand can be met through existing 11/33kV DNO grid connections which will already be coming under greater pressure from increased housing demand (both existing houses increasing circuit capacity, and new build). That will happen as a result of the movement to electric vehicle charging and to ground source heat pumps for heating.

The prevailing thought at the moment is that there will need to be battery storage at those termini and intermediate stations where IPEMU stock will be charged, on the basis that IPEMU charging directly from the grid won't be possible.

Perhaps you might be a little more helpful and give us some figures, then?

I'm sorry, but I've missed your figures to critique. I've quoted all of this repeatedly (and it has been ignored, repeatedly, whilst the crayon eating has continued) but in the real world, there are very serious and significant concerns.

Bombardier's Class 379 had just under 500kWh of battery capacity which provided for a useful range of 75km. I'd expect maybe 20% increase in range to 90km with lighter Aventra stock and more efficient ancillaries, but 500kWh is a useful number to work on. If you take 1 hour to recharge that then your electrical load will be 500kW (I'm being generous and ignoring losses and the need to keep the unit powered up, heated/cooled, battery pack temperature control etc) but that's where we are. If we cut the recharging time to 6 minutes (1/10th) then the electrical load jumps from 500kW to 5000kW (5MW) which is an unfortunate number - that's broadly the limit of a stationary pantograph carbon, it's the point it'll catch fire, in fact.

I'd like to say we won't be looking at that, but we in fact are, we have to. 75km of range isn't particularly large when you've got a train that's quite capable of averaging 75km/h and which quite possibly will need to run at higher speeds for pathing purposes. Which means we need to think about how to get close to 500kW into the battery pack every hour. It's not any better trying to get 250kW in over a 2 minute station stop, as suddenly your load moves up to 7.5MW for those 2 minutes.

That's an enormous stress to put on the grid for those 2 minute periods, so to smooth out the load, it's likely that you'll have battery or super conductor storage to suck in maybe 1MW continously and allow multiple short recharges to be made by several units each hour.

The options around that are to have recharging taking place for several minutes either side of the station, by discontinuous electrification, but one tends to find most of the obstacles for electrification, the inconveniences such as bridges, platform canopies, signalling, tunnels, level crossings and the like, all tend to be on, around or near stations, so not only will short stretches of discontinous electrification be difficult around stations, charging at stations themselves could be difficult.

Or rather, do it properly and don't go down the route of spaffing away billions on battery powered rolling stock and the infrastructure needed to charge them, when more OLE may well be more cost effective in the medium to long term.

 

[Irascible]

It's not entirely clear how the electrical demand can be met through existing 11/33kV DNO grid connections which will already be coming under greater pressure from increased housing demand (both existing houses increasing circuit capacity, and new build). That will happen as a result of the movement to electric vehicle charging and to ground source heat pumps for heating.

The prevailing thought at the moment is that there will need to be battery storage at those termini and intermediate stations where IPEMU stock will be charged, on the basis that IPEMU charging directly from the grid won't be possible.

One might hope that ilocal storage is done at the distribution level ( probably not a good idea at the final local substation level given solutions might be potentially explosive ) rather than the consumer level or at least *as well as* home/business storage etc, once there's decent engineering solutions available. That does sound heavily optimistic, yes, but given the only really predictable renewable source is tidal ( I guess hydro too, but reservoirs tend to have horrible methane emissions ) distributed storage does have to happen anyway.

Unfortunately I suspect there won't be cash to wire everything for a long while, so what happens when diesel is verboten...

 

[Bletchleyite]

I'd like to say we won't be looking at that, but we in fact are, we have to. 75km of range isn't particularly large when you've got a train that's quite capable of averaging 75km/h and which quite possibly will need to run at higher speeds for pathing purposes. Which means we need to think about how to get close to 500kW into the battery pack every hour. It's not any better trying to get 250kW in over a 2 minute station stop, as suddenly your load moves up to 7.5MW for those 2 minutes.

Thanks for that.

That depends on what it's going to be used for. That sort of range gives you a couple of return trips on most of the sort of short branch lines that this would be envisaged for (Windermere, the Thames Valley branches, St Albans if it wasn't wired already, the short Merseyrail extensions to Wigan/Skem, Burscough Bridge and Ellesmere Port and the likes). And those lines are generally low-speed, too.

It certainly does call into question longer lines like Uckfield and Barrow - though Barrow does get to sit under 25kV for much longer for each trip because it runs from Manchester Airport, so that might still work.

Or rather, do it properly and don't go down the route of spaffing away billions on battery powered rolling stock and the infrastructure needed to charge them, when more OLE may well be more cost effective in the medium to long term.

In the vast majority of cases I agree.

 

[Philip Phlopp]

Thanks for that.

That depends on what it's going to be used for. That sort of range gives you a couple of return trips on most of the sort of short branch lines that this would be envisaged for (Windermere, the Thames Valley branches, St Albans if it wasn't wired already, the short Merseyrail extensions to Wigan/Skem, Burscough Bridge and Ellesmere Port and the likes).

It certainly does call into question longer lines like Uckfield and Barrow - though Barrow does get to sit under 25kV for much longer for each trip because it runs from Manchester Airport.

The charging issue is most specific to IPEMUs which don't have much/any time charging on 25kV during other parts of their journey. If they can do battery charging whilst running under the wires, use that stored energy to cover the section of track which isn't electrified, and get back to the OLE either elsewhere on the journey or on the return working, charging is much less of an issue, or ceases to be an issue at all. It's those out and back workings where there's only a short distance under OLE that's the real problem.

 

[HST43257]

I'm sorry, but I've missed your figures to critique. I've quoted all of this repeatedly (and it has been ignored, repeatedly, whilst the crayon eating has continued) but in the real world, there are very serious and significant Bombardier's Class 379 had just under 500kWh of battery capacity which provided for a useful range of 75km. I'd expect maybe 20% increase in range to 90km with lighter Aventra stock and more efficient ancillaries, but 500kWh is a useful number to work on. If you take 1 hour to recharge that then your electrical load will be 500kW (I'm being generous and ignoring losses and the need to keep the unit powered up, heated/cooled, battery pack temperature control etc) but that's where we are. If we cut the recharging time to 6 minutes (1/10th) then the electrical load jumps from 500kW to 5000kW (5MW) which is an unfortunate number - that's broadly the limit of a stationary pantograph carbon, it's the point it'll catch fire, in fact.

So could you have 2 batteries in circulation, with one being charged while the other is in operation? Take the Marks Tey to Sudbury branch: One battery could do the shuttle for 45 minutes (MKT-MKT) then a quick changeover (15 mins allowed with less time at Sudbury) and the other battery, which has just been charged, replaces the used one (which is then charged) and the cycle repeats.

 

[Jozhua]

Moderator note: Split from https://www.railforums.co.uk/threads/cuts-to-investment-in-rail-infrastructure.211931

Interesting that buying high performance modern trains rather than outdated low performance ones that are outrun by 40yr old HSTs is now a problem...

If batteries and bimodes can match the journey times, perhaps electrification has had its day.

It's about more than just journey times, it's about:
-Reduced overall energy consumption
-Quieter trains
-Simpler trains to build - cheaper
-More reliable trains
-Less maintainence, trains are lighter so wear track less, as well as being simpler to maintain themselves.
-No dealing with refuelling, or recharging, you could run non-stop until the wheels fall off!
-Oh, and that whole climate change thing...

Has electrification had it’s day? No. It’s only just getting started. I can’t emphasise the importance of electrifying our rail network AND completing our transition to clean energy supplies. Batteries have they own problems regarding production & disposal that are not as prevalent with electric trams & trains.

Not to mention using batteries means lugging the things round with you the whole time, which either uses more energy or affects performance.

And increases wear on the track!

Definitely not. Batteries, while the best option for road traffic and possibly small branch lines[1], do have environmental issues that OHLE doesn't.

[1] For genuine branch lines I'd go more down a light rail line - DC OHLE, light rail style vehicles (e.g. the high floor Metrolink trams, but in some cases low-floor may make sense), track brakes so level crossings can stay open safely, level boarding etc.

AC these days has the same clearances as DC, with current protection and the like. I think there are perhaps prospects for reducing currents in areas, remembering AC is easier to change voltages as well.

But running branches in a light rail fashion probably isn't a bad idea - the only concern I would have is top speed when joining the mainline. Although this is mostly down to wheel shapes and hunting oscillation, so providing carriages are of a certain length and curves aren't too tight, it should be fine.

I think settling for level boarding at the 900-ish mm standard is sensible.

 

[Energy]

So could you have 2 batteries in circulation, with one being charged while the other is in operation? Take the Marks Tey to Sudbury branch: One battery could do the shuttle for 45 minutes (MKT-MKT) then a quick changeover (15 mins allowed with less time at Sudbury) and the other battery, which has just been charged, replaces the used one (which is then charged) and the cycle repeats.

Changing over the entire battery pack would be require a lot of effort and extra staff and equipment.

 

[HST43257]

Changing over the entire battery pack would be require a lot of effort and extra staff and equipment.

Surely a few extra staff and a bit of cash spent on land and equipment is worth it if it means work is being done to safe our environment.