Do The Emperor's New Bi-Modes Affect Any Business Cases?

[FQTV]

The apparent cooling of government towards further overhead electrification, and the championing of forthcoming bi-modes instead, prompts me to wonder weather any station and/or line (re)openings would warrant reconsideration in that light.

As an example, does the existing business case for The Leamside Line account for the implications of Transpennine electrification and the routing, pathing and service opportunities that might present?

If plans were hitherto generally for an increase in electric traction, an unelectrified Leamside would be compromised in its utility.

Would or should any cancellation of Transpennine electrification, and greater development of fully or partially self-powered traction, therefore change how a line such as Leamside might be utilised, and by default its business case?

Likewise any others around the country.

 

[NotATrainspott]

The apparent cooling of government towards further overhead electrification, and the championing of forthcoming bi-modes instead, prompts me to wonder weather any station and/or line (re)openings would warrant reconsideration in that light.

As an example, does the existing business case for The Leamside Line account for the implications of Transpennine electrification and the routing, pathing and service opportunities that might present?

If plans were hitherto generally for an increase in electric traction, an unelectrified Leamside would be compromised in its utility.

Would or should any cancellation of Transpennine electrification, and greater development of fully or partially self-powered traction, therefore change how a line such as Leamside might be utilised, and by default its business case?

Likewise any others around the country.

The Leamside line would almost certainly be electrified if reopened. Otherwise, existing electric services would need to be converted back to diesel in order to run on it. In my view the most likely reopening would be as a higher-speed bypass of Durham, leaving the existing route for use by stopping passenger and freight services. There's not a lot of point in reopening a slow freight route when the existing line isn't exactly fast either. It's a reasonably likely option for NPR improvements, as it would cause significant journey time and capacity improvements for almost all services in the North East.

Also, when you would be reopening a line from scratch, the cost of electrification would be much more manageable. The line would get a totally modern track formation and signalling immune to electrification in any case. Various bridge rebuilds or replacements would be required anyway, especially if speeds were increased, meaning there would be little extra cost needed to provide clearance. Electrification teams would be able to work all day on a proper construction site, not an operational railway. They could either use rail-based tools after the track is laid, or they could use truck-mounted tools before the tracks are installed. The latter option was how recent LGV lines were built.

 

[xotGD]

You could run Leeds - Skipton - Colne with bimodes.

 

[daikilo]

The apparent cooling of government towards further overhead electrification, and the championing of forthcoming bi-modes instead, prompts me to wonder weather any station and/or line (re)openings would warrant reconsideration in that light.UNQUOTE]

In essence, a decision not to electrify a part of the network but instead to provide brand-new bi-mode trains could affect many past decisions and business cases. However, whether it will change the outcome will depend on many factors including whether the decision makes the offer less attractive to the customer e.g. if TPE services are slower because bi-modes have to be used instead of through electric it could impact on the attractiveness of feeder services.

As regards reopenings/new routes, because a bi-mode is more flexible in operational terms, in theory they reduce the cost of the infrastructure therefore making that part of the equation more attractive.

One thing is also certain i.e. once the bi-modes are bought, the attractiveness of electrification of the parts of routes on which they are used diminishes unless another equally financially attractive use can be found for them.

 

[RichmondCommu]

If we can't find the funds to electrify the MML up to Sheffield how does anyone think that the money will be found to build new railways other than HS2?

 

[The Ham]

If we can't find the funds to electrify the MML up to Sheffield how does anyone think that the money will be found to build new railways other than HS2?

Probably the answer to that is; if other contribute towards the costs then the government is more likely to find the funding (mostly as the government's CBR improve the less money that needs to be put in by the government).

As such expect projects like Crossrail 2 (once how much funding London is providing up front has been sorted), which are part funded by local taxes/tax payers and/or local developments making contributions towards them.

 

[tbtc]

Emperor’s New Clothes? Surely the point of that story was that the Emperor wasn’t wearing any? Nobody is denying that bi-modes have some pros and some cons (we just argue about which are more significant).

Yes, they aren’t as perfect at being a DMU as a high-spec DMU would have been, and they aren’t as perfect at being an EMU as a high-spec EMU would have been. But given the reality of our botched electrification, they seem the best compromise we could hope for.

Many of the re-openings that we discuss on here tend to be the quaint rural branchlines that would never have a hope of being electrified (e.g. Carmarthen to Aberystwyth, Tavistock to Okehampton), so I don’t think that bi-modes would affect the case for them.

Will bi-mode improve the business case for the Leamside? Depends on what the purpose of a Leamside re-opening would be. Is it to divert slow moving freight away from Durham, so that there’s more scope for passenger services on the existing line? In which case there seems little need for electrification, given the lack of electrified freight on the ECML.

Or is it a new fast alignment to take the LDHS services away from Durham (to speed them up), in which case electrification does matter. But then there'll be diesel-only Voyagers on the ECML that aren't affected by electrification.

Or would it be predominantly a commuter shuttle from Washington to Newcastle (as part of the Northern franchise), in which case it may diesel operated, given the lack of EMUs on other local trains?

Regardless, a new station on the outskirts of Edinburgh recently cost over forty million pounds to build. Forty million pounds. Just for a two platform station on an existing line (not built in a tunnel, not requiring additional trackwork, just a common-or-garden new station). Given the way that those kind of expenses have escalated in recent years, I think that we have bigger problems to worry about (when dealing with the “cost” element of a BCR) than bi-modes.

when you would be reopening a line from scratch, the cost of electrification would be much more manageable. The line would get a totally modern track formation and signalling immune to electrification in any case. Various bridge rebuilds or replacements would be required anyway, especially if speeds were increased, meaning there would be little extra cost needed to provide clearance. Electrification teams would be able to work all day on a proper construction site, not an operational railway. They could either use rail-based tools after the track is laid, or they could use truck-mounted tools before the tracks are installed. The latter option was how recent LGV lines were built.

Agreed - much simpler with new lines (than trying to schedule possessions on operational lines)

If we can't find the funds to electrify the MML up to Sheffield how does anyone think that the money will be found to build new railways other than HS2?

Fair point.

I think that we can probably forget about most ambitions for new lines, given the electrification overspends. I doubt a Government of any colour would feel confident handing NR a cheque to deliver those kind of schemes, sadly.

 

[CdBrux]

For a TOC running a bi-mode is it cheaper for them to run in electric mode or diesel and does that depend on the terrain / stopping pattern? In other words what incentives would the TOC have to electrify certain sections of line. In addition for frequent stoppers for sure there are acceleration benefits to electric leading eventually to faster times and possibly less stock needs.

If future enhancement investments are to have a greater TOC input to better reflect customer needs could this mean a more patchy electrification focussed on where it best makes a difference? I had understood for example that GWR would maybe prioritise electrification of the hilly Devon section over say Bristol to Exeter. With bi-modes that becomes a possibility as it is less important that it would be in isolation from other electric schemes.

 

[squizzler]

The bi mode seems to have greatly increased the engineering required for OLE. Whilst the bi-mode allows trains to split en route so that sections can head to destinations on non-electric routes, this flexibility requires the electrification to be able to handle trains consisting of several short sections each with their pantograph up.

Hence the heavy construction of the Series 1 OLE. Hopefully this over-engineering will pay dividends when bi-modes are zipping up and down in formation. In terms of the reference to a business case, the outlay is greater, but hopefully so are the benefits as virtually all trains under the wires will be using a pantograph.

 

[daikilo]

The bi mode seems to have greatly increased the engineering required for OLE. Whilst the bi-mode allows trains to split en route so that sections can head to destinations on non-electric routes, this flexibility requires the electrification to be able to handle trains consisting of several short sections each with their pantograph up.

Hence the heavy construction of the Series 1 OLE. Hopefully this over-engineering will pay dividends when bi-modes are zipping up and down in formation. In terms of the reference to a business case, the outlay is greater, but hopefully so are the benefits as virtually all trains under the wires will be using a pantograph.

Firstly, I don't think the fact that they are bi-modes has any impact on the OHLE as such.

What might is that even before the decision to cutback electrification, some sets were to be 5-car and occasionally operate in multiple. It may well be that it was deemed that to permit speeds of 125mph the line would have to be at a higher tension thus requiring a heavier OHLE structure.

Paradoxically, the fact that the short sets are bimode, could theoretically allow one of them to operate in diesel mode with the other in electric thus with only one pantograph raised!

 

[notlob.divad]

For a TOC running a bi-mode is it cheaper for them to run in electric mode or diesel and does that depend on the terrain / stopping pattern? In other words what incentives would the TOC have to electrify certain sections of line. In addition for frequent stoppers for sure there are acceleration benefits to electric leading eventually to faster times and possibly less stock needs.

If future enhancement investments are to have a greater TOC input to better reflect customer needs could this mean a more patchy electrification focussed on where it best makes a difference? I had understood for example that GWR would maybe prioritise electrification of the hilly Devon section over say Bristol to Exeter. With bi-modes that becomes a possibility as it is less important that it would be in isolation from other electric schemes.

Surely the benefit to acceleration and hill climbing with EMUs is that they are in general lighter than an equivalent DMU. Therefore with the Bi-modes you can't just string the wires up where you want the fast acceleration or on the hilly section, as you still have to accelerate of lift the weight of the diesel gen sets.

 

[notlob.divad]

The bi mode seems to have greatly increased the engineering required for OLE. Whilst the bi-mode allows trains to split en route so that sections can head to destinations on non-electric routes, this flexibility requires the electrification to be able to handle trains consisting of several short sections each with their pantograph up.

Hence the heavy construction of the Series 1 OLE. Hopefully this over-engineering will pay dividends when bi-modes are zipping up and down in formation.

I too don't think this relates to it being bi-mode, more the intended top speed of the line and the decision to run doubled up formations.

In terms of the reference to a business case, the outlay is greater, but hopefully so are the benefits as virtually all trains under the wires will be using a pantograph.

It may strengthen the business case on highly utilised sections of track, whilst equally weakening the case on lightly used sections of track. You could say it will have a polarising effect.

 

[rebmcr]

Even before the decision to cutback electrification, some sets were to be 5-car and occasionally operate in multiple. It may well be that it was deemed that to permit speeds of 125mph the line would have to be at a higher tension thus requiring a heavier OHLE structure.

Almost spot-on; the reason for Series 1 is to support multiple pantographs at 140mph. It's also engineered to be tensioned and to get ripped down in a straight line, hopefully leaving adjacent tracks unaffected.

 

[squizzler]

Firstly, I don't think the fact that they are bi-modes has any impact on the OHLE as such.

What might is that even before the decision to cutback electrification, some sets were to be 5-car and occasionally operate in multiple. It may well be that it was deemed that to permit speeds of 125mph the line would have to be at a higher tension thus requiring a heavier OHLE structure.

Paradoxically, the fact that the short sets are bimode, could theoretically allow one of them to operate in diesel mode with the other in electric thus with only one pantograph raised!

I think bi modes are the reason for trains consisting of short formations in multiple, because bi-mode allows short sections to come from a non electrified hinterland and couple up at a mainline station for the trunk section of the journey. If you had to run electric or diesel only, passengers from stations in the non electrified hinterland might have to change trains at the mainline station from their diesel regional set into one long electric train.

I too don't think this relates to it being bi-mode, more the intended top speed of the line and the decision to run doubled up formations.

It may strengthen the business case on highly utilised sections of track, whilst equally weakening the case on lightly used sections of track. You could say it will have a polarising effect.

Agree the polarisation effect. I see the introduction of bi-modes as analogous to mobile phones. Like traditional electric trains, household phones could only work where their specific wires were installed. To begin with many people thought mobiles might let them get rid of the landline to their house. What actually happened is most people have higher spec landlines (broadband) and use them more intensively than ever before. You can make a telephone call anywhere, but when back at the house you pick up your home wifi and gain much faster service.

I think at the moment the railway press and most enthusiasts are still - as mobiles were to the landline around the late 1990's - regarding bi modes as a threat to electrification.

 

[snowball]

Surely the benefit to acceleration and hill climbing with EMUs is that they are in general lighter than an equivalent DMU.

Partly that, but mainly, I would have thought, from the fact that the maximum power available is greater, enabling higher acceleration, especially as the speed increases past the lower speed range. (Power being proportional to speed times acceleration. (Edit: that's an oversimplification but it gves an idea.))

Therefore with the Bi-modes you can't just string the wires up where you want the fast acceleration or on the hilly section, as you still have to accelerate of lift the weight of the diesel gen sets.

I disagree for the reason above.

 

[daikilo]

I think bi modes are the reason for trains consisting of short formations in multiple, because bi-mode allows short sections to come from a non electrified hinterland and couple up at a mainline station for the trunk section of the journey. If you had to run electric or diesel only, passengers from stations in the non electrified hinterland might have to change trains at the mainline station from their diesel regional set into one long electric train.

You can think what you like, and your logic is valid, but the fact is that the shorter electric sets were ordered before electrification was "cut short'. And, do the wires actually reach the places where you would propose a split?

 

[D365]

Almost spot-on; the reason for Series 1 is to support multiple pantographs at 140mph. It's also engineered to be tensioned and to get ripped down in a straight line, hopefully leaving adjacent tracks unaffected.

This. Basically, Network Rail never want another ECML again.

 

[squizzler]

You can think what you like, and your logic is valid, but the fact is that the shorter electric sets were ordered before electrification was "cut short'. And, do the wires actually reach the places where you would propose a split?

It is not hard to imagine that a five car bi-mode might come down from Worcester and attach to a second bi-mode waiting in the Oxford platform for the trunk haul up town. Or that a bi mode from Gloucester and Stroud might have coupled to an electric set at Swindon for a mainline burn-up to Paddington.

The GWR was originally conceived as a mainline with branches into nearby towns (particularly in the far west) rather than favouring a more devious route to put more centres of population on route, or having loops that head off to the hinterland and rejoin the mainline further along. There will probably be more places found where a short train can come off a branch and attach to another portion waiting at a platform ready to provide more capacity for the mainline portion of the journey. Bi-modes seem a logical response to this reality. This in turn probably determined the requirement for series 1 OLE to cope with fast trains consisting of short sections with lots of pantographs. So arguably, once again, Brunel's choices back in the day have determined another instance of parallel technological evolution in the GWR!

 

[notlob.divad]

Partly that, but mainly, I would have thought, from the fact that the maximum power available is greater, enabling higher acceleration, especially as the speed increases past the lower speed range. (Power being proportional to speed times acceleration. (Edit: that's an oversimplification but it gves an idea.))

I disagree for the reason above.

But there is an inherent assumption in your argument that no bi-mode train will ever be able to provide the same output power on diesel as on electric. I don't accept that assumption. The driving motors are the same, the electrics feeding those motors are the same, the only difference is the total generating capacity of the multiple diesel gensets v's the power available via OHLE. The only reason that current bi-mode designs have lower power output on diesel is because they have been designed that way. The places where they where envisaged to be using diesel was on the slower branch lines rather than the electrified mainlines. Therefore less generating capacity was included as the higher speed and acceleration was not required where diesel would be used.

TPE bi-modes have been designed to have a higher power output on diesel than GWR sets precisely because it was known that they would be running from diesel on quite severe gradients from the start of their operational life.

I really don't think we will ever see areas of micro electrification like just up a steep incline, yes bigger electrification schemes may extend just over the top of a steep incline for the reasons you state, but they won't be done in isolation.

 

[jimm]

But there is an inherent assumption in your argument that no bi-mode train will ever be able to provide the same output power on diesel as on electric. I don't accept that assumption. The driving motors are the same, the electrics feeding those motors are the same, the only difference is the total generating capacity of the multiple diesel gensets v's the power available via OHLE. The only reason that current bi-mode designs have lower power output on diesel is because they have been designed that way. The places where they where envisaged to be using diesel was on the slower branch lines rather than the electrified mainlines. Therefore less generating capacity was included as the higher speed and acceleration was not required where diesel would be used.

TPE bi-modes have been designed to have a higher power output on diesel than GWR sets precisely because it was known that they would be running from diesel on quite severe gradients from the start of their operational life.

I really don't think we will ever see areas of micro electrification like just up a steep incline, yes bigger electrification schemes may extend just over the top of a steep incline for the reasons you state, but they won't be done in isolation.

The places that GWR bi-modes will be used off the wires aren't exactly 'branch lines' - e.g. the Cotswold Line (with sections passed for 100mph running) will have a baseline hourly service between London and Worcester all day, plus peak extras to give roughly a 30-minute frequency at times.

The TPE bi-modes do not have a higher power output on diesel than the GWR bi-modes. The Class 802 was first ordered for GWR services to the West Country - the TPE batch are an add-on order of that variant - and the GWR 800s will now all be able to operate at the higher diesel power output as well.

When it comes to gradients, there are steeper gradients in the Cotswolds (Chipping Campden and Sapperton banks) and the Malvern Hills and in the South West than will be found between Leeds and Manchester (excepting Miles Platting bank). And services on the Cotswold routes were long planned to be worked by Class 800s with the lower power setting.

There was no plan whatever for electrification on these routes despite all these steep climbs, whereas there still is in the case of TransPennine, sort of, ish, maybe...

 

[snowball]

But there is an inherent assumption in your argument that no bi-mode train will ever be able to provide the same output power on diesel as on electric. I don't accept that assumption. The driving motors are the same, the electrics feeding those motors are the same, the only difference is the total generating capacity of the multiple diesel gensets v's the power available via OHLE. The only reason that current bi-mode designs have lower power output on diesel is because they have been designed that way. The places where they where envisaged to be using diesel was on the slower branch lines rather than the electrified mainlines. Therefore less generating capacity was included as the higher speed and acceleration was not required where diesel would be used.

Design is usually a matter of compromise and I imagine that in designing any bi-mode it would be uneconomic to put in diesel engines capable of giving the same power as the overhead line - partly because, as you say, they add weight, partly because they take up space and partly because on most routes the stretches capable of high speed are the ones most likely to be electrified. In contrast it seems to be a good investment to put in traction motors capable of using more power than the diesels can provide - they can prove their worth on the electrified sections.

Reviewing the posts above I now agree with the first sentence of your #11, if by "equivalent" you mean "having big enough engines to provide the same power as the comparator EMU". However in real life most DMUs don't do this.

 

[47802]

I think bi modes are the reason for trains consisting of short formations in multiple, because bi-mode allows short sections to come from a non electrified hinterland and couple up at a mainline station for the trunk section of the journey. If you had to run electric or diesel only, passengers from stations in the non electrified hinterland might have to change trains at the mainline station from their diesel regional set into one long electric train.



Agree the polarisation effect. I see the introduction of bi-modes as analogous to mobile phones. Like traditional electric trains, household phones could only work where their specific wires were installed. To begin with many people thought mobiles might let them get rid of the landline to their house. What actually happened is most people have higher spec landlines (broadband) and use them more intensively than ever before. You can make a telephone call anywhere, but when back at the house you pick up your home wifi and gain much faster service.

I think at the moment the railway press and most enthusiasts are still - as mobiles were to the landline around the late 1990's - regarding bi modes as a threat to electrification.

The point is if you to run through London Trains to destinations like Hull, Bradford, Huddersfield, Harrogate, etc it doesn't really make a lot of sense to have 9 car trains to those destinations when the load can once beyond the core section of the route can be accommodated in a 5 car train. Now it just so happens that most of those destinations are off wire and hence the need for the Bi-mode, so I don't see that Bi-mode is essentially the cause but it is part of the solution.

 

[snowball]

Agree the polarisation effect. I see the introduction of bi-modes as analogous to mobile phones. Like traditional electric trains, household phones could only work where their specific wires were installed. To begin with many people thought mobiles might let them get rid of the landline to their house. What actually happened is most people have higher spec landlines (broadband) and use them more intensively than ever before. You can make a telephone call anywhere, but when back at the house you pick up your home wifi and gain much faster service.

I think at the moment the railway press and most enthusiasts are still - as mobiles were to the landline around the late 1990's - regarding bi modes as a threat to electrification.

The threat is not bi-modes themselves but the way politicians use them.

 

[GRALISTAIR]

The threat is not bi-modes themselves but the way politicians use them.

I love this quote

 

[Olaf]

Bi-modes offer another cost-option for consideration along-side options such as full electrification. Essentially the problem was with NR's failure to deliver that brought about the cancellation/postponement of specific electrification projects - the final tally for the impact on funding will not be known yet, so there is the prospect of more project cancellations/postponements yet.

The key points are that bi-modes offer service flexibility not offered by vehicle configurations dependent on line-side electric supply and the option to avoid initial capital out-lay on electrification in cases where the latter would detrimentally impact the BCR of new service.

 

[Chris125]

If we can't find the funds to electrify the MML up to Sheffield how does anyone think that the money will be found to build new railways other than HS2?

Funding is irrelevant when it's no longer seen as value-for-money, I'm sure new railways must look a lot more appealing to politicians right now than another GWML-style electrification debacle.

 

[D365]

As (should be) demonstrated by HS2, it is a lot easier to start from scratch than to do piecemeal upgrades to an existing Victorian-built railway.