IEP for beginners

[RAGNARØKR]

After all the hullabaloo about it, I made a specific effort to look out for this "noise and vibration" and I completely failed to notice it. I found both rides to be smooth, quiet and pleasant. Indeed I have never noticed any untoward sounds* or vibrations on Voyager trains. I notice little difference in quality of ride between a 221 and a 390.

When they first came into service noise and vibration was dire. The ride quality was also much harder. At that time they replaced loco-hauled stock so the comparison could be made. Voygers were bad all the time they were on the Brighton services. When those were withdrawn I rarely got to travel in Voyagers again. The last few times I have been on one the overcrowding has trumped all. It may be the problem has now been solved by improving the engine mountings. And it may be a variable problem. The Danish IC3 trains have underfloor engines which are not too bad and not noticeable at all in the centre car where I normally seem to end up.

I can assure you it was not imagined.

 

[starrymarkb]

IC3 centre cars are unpowered!

 

[tbtc]

Sorry but firstly the expense and waste of dragging that dead Diesel engine under the wires is not insignificant. Over the life of IEP you would be wasting millions of kw of energy. AND they will not electrify so far then say ow we will electrify a bit more and then a few miles more. They will do the rest in one go so that blows your bi-mode for the sake of flexibility argument out of the water. Plus industry experts, who know most about this, also totally disagree with you. Bi-mode is an unnecessary waste of money and energy.

Am still waiting for your alternative, Dave.

Since a five coach IEP is lighter than a five coach Voyager, the weight of the fuel tanks seems to matter less than you think.

Voyagers at high speed are often quieter to travel in than Pendolinos. I travel regularly on both and have never heard a single person complain about internal noise or vibration on Voyagers. It's just a fixation of some railway enthusiasts, mainly the LHCS brigade and many of those were the same people who used to have their heads out of the window listening to the loco.

I agree - from the way that some people rave on about the noise of underfloor engines you'd think they were ten times louder than they actually are.

If anyone can hear the engines over the noise of all the mobile phone conversations, they are doing well!

 

[Dave1987]

The fact they are 4 cars has no relevance to anything and the Voyager design isn't appalling. The Voyager's internal design is appalling but the Meridians are basically the same train and they are pretty pleasant to travel in, as is Coach D on Virgin's Voyagers as that has a far better internal layout.

The Chiltern loco hauled trains aren't quite at all. They are probably the noisiest InterCity style trains in the country, even the new plug doors hasn't reduced the amount of noise in the passenger saloon.

Personally I'd prefer to travel in a Mk III than any of the new stock, but that is my preference and I don't claim it is the preference of everybody else, and that preference has nothing to do with noise.

Blimey which chiltern refurbed mk3's have you travelled on. I certainly don't think they are noisy at all. And that is not looking at them with rose tinted specs on either! Apart from the 165's I think all the chiltern stock is very comfortable and a nice relaxing place to travel. But a also find LM 350's very nice as well. I think replacing the HST's with a pendelino style train (subject to making windows bigger and interiors a lot better) would be very good. Then loco hauling them off the wires for the rest of the way. I certainly would not promote the idea of a diesel loco one end and electric loco the other as again that is a massive waste of energy.

 

[RAGNARØKR]

Since a five coach IEP is lighter than a five coach Voyager, the weight of the fuel tanks seems to matter less than you think.

How is that a comparison? The two trains are completely different. A proper comparison would be the five car IEP as a straight EMU and a five car IEP in its Bi-mode form. At 44 tons the Voyagers are not lightweights, and the tilting version is around 52 tons.

 

[AndyLandy]

How is that a comparison? The two trains are completely different. A proper comparison would be the five car IEP as a straight EMU and a five car IEP in its Bi-mode form. At 44 tons the Voyagers are not lightweights, and the tilting version is around 52 tons.

It's a comparison against what we have already. The comparison against EMU IEP would be relevant, but I don't think that makes this one irrelevant. The point that an IEP train is lighter than the existing DEMU traction we have dispells the myth that it'll be so heavy that it's far too expensive to run. We seemingly can afford to run Voyagers, so why not IEPs?

 

[Gareth Marston]

from Roger Fords (Modern Railways) February 2013 Columns preview e mail.

"After, after my shock-horror analysis of IEP costs in the December 2012 column, I have been waiting for some killer correction from DfT pointing out an error in my. But no.

However, Chris Williamson, the rail minded Member of Parliament for Derby North, raised the issue of IEP costs in a letter to Transport Secretary Patrick McLoughlin about the Thameslink contract. And he got am answer – sort of.

This is what Transport Minster Simon Burns replied.
"With regards to the IEP comparison, the procurement of rail vehicles is subject to open competition and costs vary between each contract depending on a number of factors. As such, making a comparison between trains that operate from different power sources, of different vehicle lengths, of different fleet sizes, on different routes, with different financing costs, different foreign exchange rates and different contractual structures is unlikely to be meaningful. In particular, capital prices will change over time depending on changes to materials and labour costs, which tend to follow different rates of inflation to RPI and so it is probable that a large portion of the discrepancy is due to cost inflation from Pendolino deployment in 2002/3 to IEP deployment in 2017/18’.

You can just hear Sir Humphrey explaining this to a baffled politician in ‘Yes Minister’. As the old saying goes, reality is funnier than satire.

 

[tbtc]

How is that a comparison? The two trains are completely different. A proper comparison would be the five car IEP as a straight EMU and a five car IEP in its Bi-mode form. At 44 tons the Voyagers are not lightweights, and the tilting version is around 52 tons.

It puts the weight of the fuel tanks into context - people don't seem to consider the weight of a loco and DVT to be excessive (over a hundred tonnes), yet the weight of the diesel tanks is seen to be a huge issue.

Since you've said that you'd replace Oxford - London services with 158s, you obviously have no problem with underfloor engines, but others do.

 

[starrymarkb]

from Roger Fords (Modern Railways) February 2013 Columns preview e mail.

"After, after my shock-horror analysis of IEP costs in the December 2012 column, I have been waiting for some killer correction from DfT pointing out an error in my. But no.

However, Chris Williamson, the rail minded Member of Parliament for Derby North, raised the issue of IEP costs in a letter to Transport Secretary Patrick McLoughlin about the Thameslink contract. And he got am answer – sort of.

This is what Transport Minster Simon Burns replied.
"With regards to the IEP comparison, the procurement of rail vehicles is subject to open competition and costs vary between each contract depending on a number of factors. As such, making a comparison between trains that operate from different power sources, of different vehicle lengths, of different fleet sizes, on different routes, with different financing costs, different foreign exchange rates and different contractual structures is unlikely to be meaningful. In particular, capital prices will change over time depending on changes to materials and labour costs, which tend to follow different rates of inflation to RPI and so it is probable that a large portion of the discrepancy is due to cost inflation from Pendolino deployment in 2002/3 to IEP deployment in 2017/18’.

You can just hear Sir Humphrey explaining this to a baffled politician in ‘Yes Minister’. As the old saying goes, reality is funnier than satire.

That is a Sir Humphrey speech if ever I saw one!

 

[RAGNARØKR]

It puts the weight of the fuel tanks into context - people don't seem to consider the weight of a loco and DVT to be excessive (over a hundred tonnes), yet the weight of the diesel tanks is seen to be a huge issue.

Since you've said that you'd replace Oxford - London services with 158s, you obviously have no problem with underfloor engines, but others do.

Please do not distort. The line is being electrified so what would be the point. They are, however, used on the Waterloo-Exeter route which is in essential ways similar to Paddington-Hereford - similar length and much less traffic the further from London you go. And the underfloor engines on the 158s are about half the power of those under a Voyager so naturally they are less intrusive.

To put the weight of the engines and fuel tanks into context. Someone needs to come up with the difference in weight between a hypothetical unpowered IEP. The comparison is then between that and a locomotive, presumably around 84 tons. The DVT is an irrelevance because the driving trailer would have the same accommodation as an end car on the IEP.

My main objection is not the cost of carrying around this unused weight but the cost of buying it in the first place and then having to maintain it. From that point of view there is no difference in principle between a locomotive sitting half the day in a siding, and carrying the same equipment, unused, under the floor for hundreds of miles a day.

 

[jimm]

To determine the extent of the issue it will eventually be necessary to run a gauging train over the routes on which it will operate. This will include a vehicle of the proposed dimensions, with soft build-outs in the centre and ends. These days, the build-outs consist of polystyrene blocks. Where curved tracks are adjacent, two such vehicles will have to be run past each other to ensure that no infringement takes place. Gauging problems due to overthrow do not arise on straight runs of track such as you have cited. So it is quite possible that the entire length of the Cotwold Line could take 26 M vehicles without difficulty. Even 26 x 2.82. Trouble arises typically, at junctions and approaches to major stations, where radii can be down to the minimum of 200 metres. There are serious difficulties if the site is in an urban area with little room for taking additional land. The junctions around Newcastle were mentioned in another thread as an example.

Due to laser surveying techniques Network Rail has a better knowledge of the infrastructure than previously but ultimately it is the train that will find the restricted clearances. Unexpected situations arise - there was no obvious reason why parts of the station had to be cut back at Shoreham - on a straight stretch of track - to accommodate the class 158.

A further issue relating to gauging is that track does not remain in one place, especially on curves where it tends to drift sideways with the passage of time. This can be controlled by regular surveying and re-aligning. It may be that the intention is to do this more frequently, enabling tolerances to be reduced, in which case there will be an ongoing cost instead.

And yet more repeated bluster. So although you have told us there will be a "major infrastructure upgrade" to allow IEP to run, they are now going to take out a gauging train, are they? But surely they must have done that already in order for you to be able to tell the world here that there is going to be a "major infrastructure upgrade"?

As for "straight runs of track" you would be hard-pressed to find any piece of track on a major GW route less straight than the redoubled Aston Magna curve, but why let the facts get in the way?

 

[RAGNARØKR]

And yet more repeated bluster. So although you have told us there will be a "major infrastructure upgrade" to allow IEP to run, they are now going to take out a gauging train, are they? But surely they must have done that already in order for you to be able to tell the world here that there is going to be a "major infrastructure upgrade"?

As for "straight runs of track" you would be hard-pressed to find any piece of track on a major GW route less straight than the redoubled Aston Magna curve, but why let the facts get in the way?

One the subject of facts, there is this document. From which it can reasonably be concluded that any departure from existing vehicle dimensions should be avoided like the plague. The real test comes when the first vehicles have been built and have to go through low speed and dynamic clearance checks.

And what is the radius of the Ashton Magna curve? Looking at the map, it does not look like the sort of curve that could cause gauging troubles. The sort of curve that could is the one visible on the same map, where the former Chipping Norton branch turned off at Kingham. Then there is the spaghetti of track around Bristol Temple Meads. And at York and Newcastle.

 

[tbtc]

Please do not distort. The line is being electrified so what would be the point. They are, however, used on the Waterloo-Exeter route which is in essential ways similar to Paddington-Hereford - similar length and much less traffic the further from London you go. And the underfloor engines on the 158s are about half the power of those under a Voyager so naturally they are less intrusive.

To put the weight of the engines and fuel tanks into context. Someone needs to come up with the difference in weight between a hypothetical unpowered IEP. The comparison is then between that and a locomotive, presumably around 84 tons. The DVT is an irrelevance because the driving trailer would have the same accommodation as an end car on the IEP.

My main objection is not the cost of carrying around this unused weight but the cost of buying it in the first place and then having to maintain it. From that point of view there is no difference in principle between a locomotive sitting half the day in a siding, and carrying the same equipment, unused, under the floor for hundreds of miles a day.

Oh, sorry, now you don't want 158s?

Remind me what your alternative to IEP would be then?

 

[Dave1987]

Please do not distort. The line is being electrified so what would be the point. They are, however, used on the Waterloo-Exeter route which is in essential ways similar to Paddington-Hereford - similar length and much less traffic the further from London you go. And the underfloor engines on the 158s are about half the power of those under a Voyager so naturally they are less intrusive.

To put the weight of the engines and fuel tanks into context. Someone needs to come up with the difference in weight between a hypothetical unpowered IEP. The comparison is then between that and a locomotive, presumably around 84 tons. The DVT is an irrelevance because the driving trailer would have the same accommodation as an end car on the IEP.

My main objection is not the cost of carrying around this unused weight but the cost of buying it in the first place and then having to maintain it. From that point of view there is no difference in principle between a locomotive sitting half the day in a siding, and carrying the same equipment, unused, under the floor for hundreds of miles a day.

Hold on a sec there is a huge different between carting around underfloor engines under the wires and a loco sat idle not using an energy in a spur. The whole point of the loco is that you don't have a Diesel engine on the train until you run out of wires. Otherwise you might as well just run a diesel traction all the way.

 

[ainsworth74]

Blimey which chiltern refurbed mk3's have you travelled on. I certainly don't think they are noisy at all.

Paul Bigland did a ALR over the summer, RAIL provided him with a decibel meter to take some measurements of the trains he used. He found that the Chiltern refurbished Mk3 was amongst the loudest and a VT 221 the quietest (I believe the measurements were made as close to the centre of the vehicle as possible and at speed).

 

[Dave1987]

Paul Bigland did a ALR over the summer, RAIL provided him with a decibel meter to take some measurements of the trains he used. He found that the Chiltern refurbished Mk3 was amongst the loudest and a VT 221 the quietest (I believe the measurements were made as close to the centre of the vehicle as possible and at speed).

Yes I read that report but I the supposed loose wires, and loud carriages etc, I have never had these and I certainly havent heard anyone saying wow it is loud in here. A class 168 is sooooo much better than a voyager as well.

 

[HSTEd]

Hold on a sec there is a huge different between carting around underfloor engines under the wires and a loco sat idle not using an energy in a spur. The whole point of the loco is that you don't have a Diesel engine on the train until you run out of wires. Otherwise you might as well just run a diesel traction all the way.

It doesn't take significant quantities of energy to haul the dead weight around.
And it means the train can also rescue itself in a wires down scenario, and probably rescue other trains around it if neccesary.

Railway traction electricity is 6.5p/kWh, red diesel comes out about 25p/kWh when you factor in the efficiency of the diesel engine.

 

[RAGNARØKR]

Paul Bigland did a ALR over the summer, RAIL provided him with a decibel meter to take some measurements of the trains he used. He found that the Chiltern refurbished Mk3 was amongst the loudest and a VT 221 the quietest (I believe the measurements were made as close to the centre of the vehicle as possible and at speed).

Interesting. Where is the noise coming from? I have not seen these trains and am unlikely to get the chance. I understand the doors between the vestibule and the saloon have been removed. Noise comes in through the gangway opening.

But noise disturbance is about more than mere decibels. Some low frequency discords can be unpleasant to have to listen to. Try it on a keyboard and you will see what I mean. A few months ago I was in a church where the organ was out of tune in the bass register. 7 Hz is reputed to be bad, as are screaming, grinding and scraping sounds generally.
--- old post above --- --- new post below ---

Oh, sorry, now you don't want 158s?

Remind me what your alternative to IEP would be then?

You seem to have a bad memory. I have said this repeatedly yet you attribute me with a suggestion that is put up only as a less bad option to IEP.

The alternative is obvious. Over-powered EMU or electric loco at the London end of the train, which may then split where the wires stop. Diesel loco hauls from the country and and pushes back in the return direction. There is nothing original about this. It is much like the Waterloo-Weymouth operation.

If that is too much trouble operationally, then run EMUs on the electrified stretch eg London to Oxbridge and acccept running under the wires for the services beyond Oxbridge ie diesel locos push pull to provide the through services from London to Barchester. Diesel traction is more fuel-efficient anyway.
--- old post above --- --- new post below ---

We seemingly can afford to run Voyagers, so why not IEPs?

Don't they have a reputation for being gas guzzlers?
--- old post above --- --- new post below ---

It doesn't take significant quantities of energy to haul the dead weight around.
And it means the train can also rescue itself in a wires down scenario, and probably rescue other trains around it if neccesary.

Probably not but all that kit has to be bought and paid for, and maintained. Which is one reason why the IEP is Britain's most expensive train ever, by a long way.

 

[D365]

I don't understand how diesel is more efficient when HSTed has just informed us that OHLE is cheaper per kWh. Why are we electrifying railways if that is the case? Or am I missing something; I somehow doubt it... Similarly, I wonder how much a pure diesel SET would weigh at current specs compared to bi-mode, as you seem to have made several suggestions for under-the-wires running. For one, this would reduce paths available as diesels (or more of them, HSTs will continue on West of England) have to be co-ordinated with electrics.

Do you have any official references from those organisations directly involved to prove any of your statements?

As an aside, some of the older German LHCS is awful for noise and heat in 35C+ temperatures... The relief as I trudged into the chilled and waiting 423 S-Bahn!

 

[HSTEd]

Probably not but all that kit has to be bought and paid for, and maintained. Which is one reason why the IEP is Britain's most expensive train ever, by a long way.

The price of the IEP came out at £2.7-3m per carriage I believe.

The price of a newbuild of Pendolinos comes out at about £2.3m/carriage supposedly.

They aren't that expenisve, its just that inflation has pushed the prices up rather drastically in ten years since the last fleet of high speed trains arrived.

 

[D365]

How much did the average Pendolino vehicle cost from the first batch and how much from the latest? Of course, it will always be an unfair comparison to IEP...

 

[The Ham]

How much did the average Pendolino vehicle cost from the first batch and how much from the latest? Of course, it will always be an unfair comparison to IEP...

As I have said previously there is no point comparing the cost per coach, as an IEP is longer and therefore has more usable space, or if you do you have to multiply the cost by 1.3 to the Pendolino coach costs so you are comparing it on a per seat basis.

The other thing that wasn't really picked up on in my post about costs is that to have the same number of seats on a Pendolino the train needs to be longer than IEP. That means one of two things, either SDO opening is used at a lot more stations (but that just increases dwell times at those stations) or platforms get lengthened (which often is costly or is not possible). As stated a 12 coach Pendolino has a similar capacity to a 9 coach IEP, that then means that at least all the major stations should be 276m long or at the very least all the bay platforms (such as the London termini) have to be this long. Whilst in a shorter platform length (260m) it is possible to fit a 10 coach IEP which will have a higher capacity.

Therefore to provide the level of capacity that an IEP can provide it is likely that when they are first brought in that there would need to be several stations where the platform lengths were looked at and if more capacity was required on the trains the cost of platform lengthening could be fairly costly. Unless several of the stations (ideally the busier ones) along the GWML & ECML happen to be at least 276m long and ideally 300m long.

To save people going looking for my post here is the relevant bit:

Cost comparisons per vehicle of a Class 390 and an IEP per vehicle are not comparing like with like. An 11 coach 390 has a capacity of 589 seats, whilst a 9 coach IEP has a capacity of 627. This then means that less IEP coaches are needed compared to 390 coaches (about 1/3), so assuming that each coach cost double the cost per seat is not, it is closer to 1.55 times the cost. If you work it backwards for the cost per seat to be the same the IEP coaches can cost 1.3 times that of the 390 coaches.

The length of an 11 coach 390 is 253m whilst a 9 coach IEP is 234m, meaning that by lengthening each station by just 7m more than would be needed for an 11 coach 390 it would enable a 10 coach IEP to call there. Which could mean that in the future the electric 9 coach IEP's could be lengthened to 10 coaches at a fairly low infrastructure cost (similar to the 11 coach lengthening of the 390 which has just happened). This would further increase capacity of the IEP's over and above the 390's, with a very minimal infrastructure cost, whilst to just to get up to 12 coaches 390s would cost a lot and would only put it a little ahead of the 9 coach IEP in terms of capacity.

--- old post above --- --- new post below ---

You seem to have a bad memory. I have said this repeatedly yet you attribute me with a suggestion that is put up only as a less bad option to IEP.

The alternative is obvious. Over-powered EMU or electric loco at the London end of the train, which may then split where the wires stop. Diesel loco hauls from the country and and pushes back in the return direction. There is nothing original about this. It is much like the Waterloo-Weymouth operation.

If that is too much trouble operationally, then run EMUs on the electrified stretch eg London to Oxbridge and acccept running under the wires for the services beyond Oxbridge ie diesel locos push pull to provide the through services from London to Barchester. Diesel traction is more fuel-efficient anyway.

Gas is more fuel efficient than electricity in our homes, yet all our lighting, computers, fans, etc are run off electricity, why is that? Because gas is good at making heat, whilst electricity is good at making things turn, light up, etc. To move an electric vehicle basicly all you need is a motor, to get the same momentum out of a, say, a car you need a full on internal combustion engine.

Even if you could supply the fuel to a car as it went along the weight of the engine would still be significant, which means that the amount of energy required would be greater than an electric vehicle where the fuel was provided as it was needed. In this way although diesel traction is more fuel efficient on like for like, it has a heavier load so is less fuel efficient. Also as stated before the cost of electricity is less per kwh compared to diesel, which makes it cheaper to use electric traction.

Don't they have a reputation for being gas guzzlers?

That was the point, even though the Voyagers guzzle fuel they can be afforded.

Probably not but all that kit has to be bought and paid for, and maintained. Which is one reason why the IEP is Britain's most expensive train ever, by a long way.

What kit? The IC125's? They as you well know from the "future of the IC125's" thread need a lot of money needs to be spent on them to keep them going (even if you are just talking about the mark 3's) and even then there is no guarantee that they will last very much longer being able to run at IC speeds (and no it's not cheaper to slow them down, as you'd need more of them and it would discourage some passengers from using the railways).

 

[Dave1987]

It doesn't take significant quantities of energy to haul the dead weight around.
And it means the train can also rescue itself in a wires down scenario, and probably rescue other trains around it if neccesary.

Railway traction electricity is 6.5p/kWh, red diesel comes out about 25p/kWh when you factor in the efficiency of the diesel engine.

So in a day how many kwh's will IEP use in just carting around the underfloor engines under the wires?

 

[tbtc]

You seem to have a bad memory. I have said this repeatedly yet you attribute me with a suggestion that is put up only as a less bad option to IEP.

The alternative is obvious. Over-powered EMU or electric loco at the London end of the train, which may then split where the wires stop. Diesel loco hauls from the country and and pushes back in the return direction. There is nothing original about this. It is much like the Waterloo-Weymouth operation.

If that is too much trouble operationally, then run EMUs on the electrified stretch eg London to Oxbridge and acccept running under the wires for the services beyond Oxbridge ie diesel locos push pull to provide the through services from London to Barchester. Diesel traction is more fuel-efficient anyway

The Waterloo-Weymouth operation that has never been repeated elsewhere, despite the number of obvious places to drag EMUs beyond the wires (Chase line, Uckfield etc)? Why is the industry not keen on this idea?

And cutting direct services? I'll let jimm answer that one...
--- old post above --- --- new post below ---

Paul Bigland did a ALR over the summer, RAIL provided him with a decibel meter to take some measurements of the trains he used. He found that the Chiltern refurbished Mk3 was amongst the loudest and a VT 221 the quietest (I believe the measurements were made as close to the centre of the vehicle as possible and at speed).

Interesting

from Roger Fords (Modern Railways) February 2013 Columns preview e mail.

"After, after my shock-horror analysis of IEP costs in the December 2012 column, I have been waiting for some killer correction from DfT pointing out an error in my. But no.

However, Chris Williamson, the rail minded Member of Parliament for Derby North, raised the issue of IEP costs in a letter to Transport Secretary Patrick McLoughlin about the Thameslink contract. And he got am answer – sort of.

This is what Transport Minster Simon Burns replied.
"With regards to the IEP comparison, the procurement of rail vehicles is subject to open competition and costs vary between each contract depending on a number of factors. As such, making a comparison between trains that operate from different power sources, of different vehicle lengths, of different fleet sizes, on different routes, with different financing costs, different foreign exchange rates and different contractual structures is unlikely to be meaningful. In particular, capital prices will change over time depending on changes to materials and labour costs, which tend to follow different rates of inflation to RPI and so it is probable that a large portion of the discrepancy is due to cost inflation from Pendolino deployment in 2002/3 to IEP deployment in 2017/18’.

You can just hear Sir Humphrey explaining this to a baffled politician in ‘Yes Minister’. As the old saying goes, reality is funnier than satire.

That is a Sir Humphrey speech if ever I saw one!

I can see Sir Humphrey's point here - there's no point in comparing the cost of apples in 2002 to the cost of oranges in 2018. Am sure a Labour MP trying to represent his Bombardier constituents would like a cheap headline, but things are more complicated than that.

 

[HSTEd]

So in a day how many kwh's will IEP use in just carting around the underfloor engines under the wires?

Using RSSB figures for the Class 390 as a benchmark for EMU energy usage per tonne kilometre....

From data supplied here a figure of approximately 0.037kWh per tonne kilometre can be derived.

If we use a figure of 50 tonnes for the traction equipment in an ECML full length bi-mode set, we derive a figure of roughly 1.85kWh per set kilometre.

A typical diagram might be one and a half round trips to Edinburgh from London, which translates to approximately 1890km of running under the wires, translating to a total of ~3496kWh expended.

Using published traction electricity prices for CP4 this translates to roughly £227.64 for the days diagram.

For reference this is the price of roughly 324 litres of red diesel, sufficient to move a 2+7 HST set some 70km.
Which is rather less than the Aberdeen-Edinburgh or Inverness-Edinburgh sections of the bi-mode diagrams.

It is really a very marginal figure.
I am attempting to find out how far a Class 67 would get using 324 litres of diesel travelling light engine as that would indicate whether or not it was more fuel cost efficient to run the locomotive or the bi-mode.

 

[Dave1987]

Using RSSB figures for the Class 390 as a benchmark for EMU energy usage per tonne kilometre....

From data supplied here a figure of approximately 0.037kWh per tonne kilometre can be derived.

If we use a figure of 50 tonnes for the traction equipment in an ECML full length bi-mode set, we derive a figure of roughly 1.85kWh per set kilometre.

A typical diagram might be one and a half round trips to Edinburgh from London, which translates to approximately 1890km of running under the wires, translating to a total of ~3496kWh expended.

Using published traction electricity prices for CP4 this translates to roughly £227.64 for the days diagram.

For reference this is the price of roughly 324 litres of red diesel, sufficient to move a 2+7 HST set some 70km.
Which is rather less than the Aberdeen-Edinburgh or Inverness-Edinburgh sections of the bi-mode diagrams.

It is really a very marginal figure.
I am attempting to find out how far a Class 67 would get using 324 litres of diesel travelling light engine as that would indicate whether or not it was more fuel cost efficient to run the locomotive or the bi-mode.

So by your figures if an IEP bi-mode set was used for just 5 days in a week £1138 would be spent in energy just in carting around the under floor engines.

If it was used for 360 days in that way £81,950 would be spent in energy.

That is in just carting around the underfloor engines for one train as well.

 

[tbtc]

Using RSSB figures for the Class 390 as a benchmark for EMU energy usage per tonne kilometre....

From data supplied here a figure of approximately 0.037kWh per tonne kilometre can be derived.

If we use a figure of 50 tonnes for the traction equipment in an ECML full length bi-mode set, we derive a figure of roughly 1.85kWh per set kilometre.

A typical diagram might be one and a half round trips to Edinburgh from London, which translates to approximately 1890km of running under the wires, translating to a total of ~3496kWh expended.

Using published traction electricity prices for CP4 this translates to roughly £227.64 for the days diagram.

For reference this is the price of roughly 324 litres of red diesel, sufficient to move a 2+7 HST set some 70km.
Which is rather less than the Aberdeen-Edinburgh or Inverness-Edinburgh sections of the bi-mode diagrams.

It is really a very marginal figure.
I am attempting to find out how far a Class 67 would get using 324 litres of diesel travelling light engine as that would indicate whether or not it was more fuel cost efficient to run the locomotive or the bi-mode.

So the marginal cost of lugging the engines over one thousand miles a day (i.e. Edinburgh - London - Edinburgh - London) works out at about the cost of one additional passenger per journey?

Fairly marginal stuff - considering that the alternative (having a separate loco to do a drag, which requires additional staff, additional movements etc) clearly has a cost too.

Cheers for the figures.

 

[Zoe]

As for Inverness, wouldn't distributed traction be quite useful for climbing Druimuachdar and Slochd as opposed to dragging an EMU?

 

[LexyBoy]

So the marginal cost of lugging the engines over one thousand miles a day (i.e. Edinburgh - London - Edinburgh - London) works out at about the cost of one additional passenger per journey?

Fairly marginal stuff - considering that the alternative (having a separate loco to do a drag, which requires additional staff, additional movements etc) clearly has a cost too.

And of course there are loads of other differences too: How to track access charges differ between running a 9-coach bi-mode versus a lighter 9-coach EMU plus heavy loco? What are the maintainence costs like for bi-mode versus loco+EMU? What happens if there's an engine failure with a bi-mode unit? How many delay minutes can be saved with bi-mode in the event of power failures or need for off-wires diversions?

I'd not be surprised if the first couple of these have larger effects than just the power used in moving the engines around. Without having all the data (and planned usage), it's not possible to work out what's the most economic option. Intuitively it seems wasteful to cart tonnes of extra steel round, but if that works out best then so be it. Railway carraiges are pretty heavy at the best of times.

 

[Dave1987]

Sorry but you are spend £80,000 a year per train extra according to those figures.

Who says having a loco hauling an EMU of the wires for the short distance that that would be is more expensive?

So the marginal cost of lugging the engines over one thousand miles a day (i.e. Edinburgh - London - Edinburgh - London) works out at about the cost of one additional passenger per journey?

Fairly marginal stuff - considering that the alternative (having a separate loco to do a drag, which requires additional staff, additional movements etc) clearly has a cost too.

Cheers for the figures

.

How much would it cost to have a loco haul an EMU off the wires?? You cannot say "Fairly marginal stuff - considering that the alternative (having a separate loco to do a drag, which requires additional staff, additional movements etc) clearly has a cost too", when you have not posted anything that says that to be true!

A loco would only be using fuel while it is hauling the EMU else it will be sat not using any fuel, whereas a bi-mode would be constantly wasting fuel and energy where ever it was. That is so eco friendly.....not