Class 93 Tri-mode Loco

[Charlie Smythe]

There may well be enhancements possible during the interim period, you only have to look at how far battery storage technology has improved over the last couple of years to see that a modest increase would be theoretically possible between prototype and production models.

Same applies to the engine. There is a marine version(CAT32B) which has something like 2200HP capability with not too much difference in terms of size and weight, so even a derated one down to say 1200KW(1600BHP) could potentially be installed.That again would give ROG even more flexibility and get to CL47 level haulage,albeit at a small fuel premium.

As for the type of loads the train would be aimed at pulling,it's not designed for competing with a 66 for maximum haulage power, it's designed to operate a medium haul of say 600-800 tonnes , which the 66 currently does, but do that job with 1/3 of the fuel costs and lower track access charges.
I still maintain they'd be better off going with the co-co option as that means lower exle load, more traction points and lower RA.

There are plenty of potential uses for this locomotive. Charter trains and stock movements probably being the two main ones seeing as they’re what ROG are currently working on. Although they could be used for light scheduled passenger workings such as sleepers or possibly LHCS day trains as well, providing of course the power is there after ETS has been taken out which would be a few hundred kW.

As for the co-co vs bo-bo argument, that just comes down to cost. A co-co is naturally more expensive than a bo-bo design and seeing as Stadler already have a working bo-bo bogie design for the UK it makes sense to use it.

 

[Energy]

In the case of a marine application there isn’t the space constraint that is found on a loco. The limiting factor in updating the engine in a 93 would likely be room for a bigger cooler and other auxiliaries.

I believe the issue with getting a 68 engine in a 93 wasn't the engine itself but they couldn't fit the cooling in.

 

[Greybeard33]

In reality it doesn't take a lot of power to keep a train moving at a reasonable speed on level track. With its AC drive certainly will be more efficient than AC/DC drive of a 66 so will claw back a little here.

According to Wikipedia, the 66 power at the rail is 91% of the engine output, so not much scope for efficiency improvements.

Would be prolonged gradients that likely to cause an issue.

Indeed.

There may well be enhancements possible during the interim period, you only have to look at how far battery storage technology has improved over the last couple of years to see that a modest increase would be theoretically possible between prototype and production models.

A modest increase in battery capacity would only equate to a few more minutes of a total power output similar to a 37 (about half of a 66). Not sustainable over a long drag such as on the Calder Valley line.

Same applies to the engine. There is a marine version(CAT32B) which has something like 2200HP capability with not too much difference in terms of size and weight, so even a derated one down to say 1200KW(1600BHP) could potentially be installed.That again would give ROG even more flexibility and get to CL47 level haulage,albeit at a small fuel premium.

If it were possible to install a more powerful engine version within the space and weight constraints, surely that would already have been specified?

There are plenty of potential uses for this locomotive. Charter trains and stock movements probably being the two main ones seeing as they’re what ROG are currently working on. Although they could be used for light scheduled passenger workings such as sleepers or possibly LHCS day trains as well, providing of course the power is there after ETS has been taken out which would be a few hundred kW.

A few hundred kW of ETS power would use a substantial proportion of the 900kW available from the diesel engine!

Is it not also envisaged that the 93 will be used for heavy freight workings that are mainly on an electrified main line, but with sections on unelectrified branches where low speeds would be acceptable?

 

[hooverboy]

There are plenty of potential uses for this locomotive. Charter trains and stock movements probably being the two main ones seeing as they’re what ROG are currently working on. Although they could be used for light scheduled passenger workings such as sleepers or possibly LHCS day trains as well, providing of course the power is there after ETS has been taken out which would be a few hundred kW.

As for the co-co vs bo-bo argument, that just comes down to cost. A co-co is naturally more expensive than a bo-bo design and seeing as Stadler already have a working bo-bo bogie design for the UK it makes sense to use it.

the bo-bo vs co-co isn't purely down to cost, there are things like adhesion points/brakforce in adverse weather that need to be considered.co-co is initially more expensive to produce and a bit more to maintain, but does have it's advantages.
Stadler also have co-co varieties of eurodual I believe.

 

[Charlie Smythe]

I believe the issue with getting a 68 engine in a 93 wasn't the engine itself but they couldn't fit the cooling in.

The 68 engine was never going to be even close to fitting in the 93 due to our restricted loading gauge. Also, without it being an RA8 or above loco, the class 93 would have been well over weight.

A few hundred kW of ETS power would use a substantial proportion of the 900kW available from the diesel engine!

Yes, it would but considering that 1 ETS unit is equal to 5kW of electrical consumption, 200kW isn’t really all that much. The BR mk4’s (unlikely to be hauled by this loco but it’s an example) are ETS level 6 meaning that 7 mk4’s would be enough to reach an ETS requirement of 200kW.

I know it’s not a major deal, but this is the point I make when people ask why the the 93 cannot be used on the the Night Rivera. The loco has enough power to haul the coaches, but once you take the ETS draw from the locos overall power rating, it becomes clear that anything with less then what the 57’s have not is unsuitable. This is especially the case with sleeper cars for obvious reasons.

Is it not also envisaged that the 93 will be used for heavy freight workings that are mainly on an electrified main line, but with sections on unelectrified branches where low speeds would be acceptable?

Yes it is. Stock moves and the occasional charter and a bit of breakdown recovery is where this loco will come into its own. This is very much an electric loco with a bit of diesel capability. It is not an true half and half loco.

 

[Greybeard33]

The 68 engine was never going to be even close to fitting in the 93 due to our restricted loading gauge

I understand the 68 engine would not even fit in a 68 if modified to comply with Stage IIIb emissions requirements. That is why no more 68s can be built.

 

[Charlie Smythe]

I understand the 68 engine would not even fit in a 68 if modified to comply with Stage IIIb emissions requirements. That is why no more 68s can be built.

It’s unfortunate really as the 68 is a useful loco and is a good performer. It maybe possible to fit a smaller engine into the 68 body that does comply with with the Stage IIIb emissions standards to allow for continued production, albeit at a lower spec then the initial 68 design.

 

[Richard Scott]

According to Wikipedia, the 66 power at the rail is 91% of the engine output, so not much scope for efficiency improvements.

A book I gave quotes power at rail as 2480hp, roughly 80%, which is more typical of an AC/DC drive.

 

[Charlie Smythe]

A book I gave quotes power at rail as 2480hp, roughly 80%, which is more typical of an AC/DC drive.

I wonder how that 80% figure compares to the previous generation of diesel loco such as the 56’s, 58’s and 60’s and also the previous generation to that with the 50’s, 47’s and 37’s. I would imagine that there has been a significant gain in efficiency through out the generations with the 68’s and 93’s being more efficient than the 66’s and the 66’s be more efficient than the 60’s and so on until you get back to the early diesel electrics.

 

[43096]

I wonder how that 80% figure compares to the previous generation of diesel loco such as the 56’s, 58’s and 60’s and also the previous generation to that with the 50’s, 47’s and 37’s. I would imagine that there has been a significant gain in efficiency through out the generations with the 68’s and 93’s being more efficient than the 66’s and the 66’s be more efficient than the 60’s and so on until you get back to the early diesel electrics.

Class 60 quoted as 2,415hp at rail from 3,100hp, or 78% - comparable with Class 66.

 

[Richard Scott]

I wonder how that 80% figure compares to the previous generation of diesel loco such as the 56’s, 58’s and 60’s and also the previous generation to that with the 50’s, 47’s and 37’s. I would imagine that there has been a significant gain in efficiency through out the generations with the 68’s and 93’s being more efficient than the 66’s and the 66’s be more efficient than the 60’s and so on until you get back to the early diesel electrics.

Not much to gain really as losses are due to resistance value and current. AC machines are more efficient as less heating losses. Unless we can cheaply manufacturer superconductive materials cheaply that operate at high temperatures don't see things improving much.

 

[Charlie Smythe]

Class 60 quoted as 2,415hp at rail from 3,100hp, or 78% - comparable with Class 66.

So only a marginal gain then from the class 60 to the class 66, but I suppose that small gain probably does make a difference in the real world.

Not much to gain really as losses are due to resistance value and current. AC machines are more efficient as less heating losses. Unless we can cheaply manufacturer superconductive materials cheaply that operate at high temperatures don't see things improving much.

It will be interesting to see what efficiency gain over the Class 66 the Class 93 will have, if any of course. I’m just waiting for someone to suggest a return to hydraulic traction...

 

[43096]

So only a marginal gain then from the class 60 to the class 66, but I suppose that small gain probably does make a difference in the real world.

Class 60: 2,415hp of 3,100hp = 77.9%
Class 66: 2,480hp of 3,200hp = 77.5%

So the Class 66 is a very slight backward step. As you say, it makes little difference.

 

[Charlie Smythe]

Class 60: 2,415hp of 3,100hp = 77.9%
Class 66: 2,480hp of 3,200hp = 77.5%

So the Class 66 is a very slight backward step. As you say, it makes little difference.

Ah, I was basing my point of the back off Richard Scott’s suggestion of 80% efficiency. It’s clear to see from this data that all locos are basically the same in terms of power at the rail efficiency.

 

[supervc-10]

It isn't designed to work on batteries alone, they work together with the engine

Makes sense with my Prius analogy- battery only is for 'shunting work', doing any real work requires the engine on.

One thing I did wonder about is the possibility of an articulated loco. I know in some parts of the world there are very heavy duty articulated locos, I was wondering if that might give better bi/tri-mode performance than a 93 would, given the restrictions of fitting a large diesel engine into the UK loading gauge and still meeting emissions regs.

 

[furnessvale]

Makes sense with my Prius analogy- battery only is for 'shunting work', doing any real work requires the engine on.

One thing I did wonder about is the possibility of an articulated loco. I know in some parts of the world there are very heavy duty articulated locos, I was wondering if that might give better bi/tri-mode performance than a 93 would, given the restrictions of fitting a large diesel engine into the UK loading gauge and still meeting emissions regs.

Yes, a full scale articulated Bo-Bo-Bo would allow 6 powered axles with a diesel engine in one half of the body and the OHL electric equipment in the other. For true bi-mode operation, both diesel and electric traction modes need to be closely matched. Sadly the 88 falls well short of this target and the 93 is not that much better. Both of these bi-modes are OK for short off wire trips, or emergency recovery, but neither is up to the job of bringing a heavy liner from Felixstowe to the WCML via Ely etc.

 

[hwl]

It’s unfortunate really as the 68 is a useful loco and is a good performer. It maybe possible to fit a smaller engine into the 68 body that does comply with with the Stage IIIb emissions standards to allow for continued production, albeit at a lower spec then the initial 68 design.

You now have to comply with Stage V. The problem isn't the engine itself but the space for the DPF you need to fit for IIIB or the even bigger one for stage V.

Class 60: 2,415hp of 3,100hp = 77.9%
Class 66: 2,480hp of 3,200hp = 77.5%

So the Class 66 is a very slight backward step. As you say, it makes little difference.

The newer 3 phase drive diesel locomotives will be just over 90% transmission efficient (in higher notches) for comparison with starting tractive efforts at least 30% greater than AC alternator - DC traction motor locos (e.g. 60, 66) and continuous tractive effort at least 60% better.

The biggest differences are in tractive effort which is what actually matters (especially in lower notches were much more gets to the wheels).

All these measures of transmission efficiency also include powering auxiliary loads for example compressors, cooling fans etc. so the electronics are slightly better than the numbers appear.

 

[themiller]

Makes sense with my Prius analogy- battery only is for 'shunting work', doing any real work requires the engine on.

One thing I did wonder about is the possibility of an articulated loco. I know in some parts of the world there are very heavy duty articulated locos, I was wondering if that might give better bi/tri-mode performance than a 93 would, given the restrictions of fitting a large diesel engine into the UK loading gauge and still meeting emissions regs.

Rather that design a new bi-mode loco with a high diesel power, why not have a detachable diesel section which doesn’t need to be hauled around under the wires. Something radical like putting a class 68 on the front of the train at the end of the wires! Better still take the electric loco off so the diesel doesn’t have to drag it’s dead weight. Changing locos used to be common in this country (and still is in some). Maybe it’s a lost art that needs rediscovering.

 

[Bluejays]

These look like fantastic pieces of kit. While obviously the engine and battery function seems to be intended as a last mile feature rather than being for sustained bi -mode work. I do clthink that 110 mph top speed on electric does maybe open up the potential they could work longer stretches away from the wires at times, with sympathetic signalling and the right route they could surely take one hell of a lot of momentum out of electric stretches, with the engines and battery then kicking in , they could presumably keep up a good lick for quite a distance past the wires. If decarbonising the railway remains a priority, and electrification remains patchy we could end up needing creative solutions.

Quite obviously to anyone reading, i'm not an engineer . But if this class 93 is as good as it looks, it seems to provide a brilliant opportunity to remove an absolutely massive amount of emissions from certain freight flows. Something to be very excited about for the modern railway

 

[Dunfanaghy Rd]

Rather that design a new bi-mode loco with a high diesel power, why not have a detachable diesel section which doesn’t need to be hauled around under the wires. Something radical like putting a class 68 on the front of the train at the end of the wires! Better still take the electric loco off so the diesel doesn’t have to drag it’s dead weight. Changing locos used to be common in this country (and still is in some). Maybe it’s a lost art that needs rediscovering.

Unlikely to be a convenient yard near the changeover point. An odd couple of sidings out in the sticks won't do. Over and above the likelihood of the antisocial messing with an unattended loco, there is the matter of acceptance into a yard, and brake testing after the power change. Not a runner, I feel.
Pat

 

[hooverboy]

These look like fantastic pieces of kit. While obviously the engine and battery function seems to be intended as a last mile feature rather than being for sustained bi -mode work. I do clthink that 110 mph top speed on electric does maybe open up the potential they could work longer stretches away from the wires at times, with sympathetic signalling and the right route they could surely take one hell of a lot of momentum out of electric stretches, with the engines and battery then kicking in , they could presumably keep up a good lick for quite a distance past the wires. If decarbonising the railway remains a priority, and electrification remains patchy we could end up needing creative solutions.

Quite obviously to anyone reading, i'm not an engineer . But if this class 93 is as good as it looks, it seems to provide a brilliant opportunity to remove an absolutely massive amount of emissions from certain freight flows. Something to be very excited about for the modern railway

I was under the impression that the cl93's having an uprated diesel plant was to provide a full blown all purpose service in both modes.the cl88 diesel mode is very definitely "last mile" for heavy or medium haul freight.

The cl93 is aiming at motive power typical of cl37 or pair of 20's.the proposed specs do seem a little underrated for that purpose,but I did envision there could be enhancements to truly make that step up.

 

[hooverboy]

Unlikely to be a convenient yard near the changeover point. An odd couple of sidings out in the sticks won't do. Over and above the likelihood of the antisocial messing with an unattended loco, there is the matter of acceptance into a yard, and brake testing after the power change. Not a runner, I feel.
Pat

would seem like an awful lot of yime consuming shunting and faffing about. It would be easier in such a case to double head/top and tail two dual purpose loco's with equivalent output in both modes.
having the two loco's would also mean that when running light or ECS,one could be turned off and dragged,

 

[Charlie Smythe]

Rather that design a new bi-mode loco with a high diesel power, why not have a detachable diesel section which doesn’t need to be hauled around under the wires. Something radical like putting a class 68 on the front of the train at the end of the wires! Better still take the electric loco off so the diesel doesn’t have to drag it’s dead weight. Changing locos used to be common in this country (and still is in some). Maybe it’s a lost art that needs rediscovering.

If this were the old days they would probably do such a thing. In a time where every station had a yard and every yard had 5 locos ready to go changing locos was fine, but these days where spare locos aren't always sitting around it becomes difficult. Also, a loco left in the middle of no where is a prime target for vandals.

 

[Dunfanaghy Rd]

In Modern railways this month Ian Walmsley floats the idea of a twin loco, which would give room for all the bells and whistles (1 transformer, 1 engine/generator, 1 battery bank, 1 compressor, 1 brake frame) and save on 2 cabs compared with a 2 loco lash-up.
Pat

 

[Speed43125]

In Modern railways this month Ian Walmsley floats the idea of a twin loco, which would give room for all the bells and whistles (1 transformer, 1 engine/generator, 1 battery bank, 1 compressor, 1 brake frame) and save on 2 cabs compared with a 2 loco lash-up.
Pat

Essentially a DRS 88+68 lash up, but that doesn't require the 88 to lead...

 

[Nottingham59]

the 93 .... is [not] up to the job of bringing a heavy liner from Felixstowe to the WCML via Ely etc.

Genuine question: Could you explain what/where the problem would be? With only 1.3MW in diesel/hybrid mode the acceleration of a Class 93 would drop off before that of a 2.5MW Class 66, but the tractive effort at starting would be about the same. Is that route particularly hilly? Or is it the delays that would be caused by slower starts out of freight loops? Maintaining speed on level track wouldn't need anywhere near 1.3MW would it?

 

[172007]

Would love to see

Genuine question: Could you explain what/where the problem would be? With only 1.3MW in diesel/hybrid mode the acceleration of a Class 93 would drop off before that of a 2.5MW Class 66, but the tractive effort at starting would be about the same. Is that route particularly hilly? Or is it the delays that would be caused by slower starts out of freight loops? Maintaining speed on level track wouldn't need anywhere near 1.3MW would it?

That's my angle. Someone said 10 mins worth of battery. If you can get upto line speed of 75mph in 10 mins (not a clue, over to any freight drivers) then as the power to maintain speed drops off the spare power is then used to charge the battery (as per press release says it can) for the next incline when extra power is required. This would also guarantee a full battery when starting away. So would this change it from a last mile capability to effectively a class 37. Clearly some routes would not be suitable but we are not talking about that with most of the liner routes I am aware of. Time will tell I guess.

 

[Mollman]

Rather that design a new bi-mode loco with a high diesel power, why not have a detachable diesel section which doesn’t need to be hauled around under the wires. Something radical like putting a class 68 on the front of the train at the end of the wires! Better still take the electric loco off so the diesel doesn’t have to drag it’s dead weight. Changing locos used to be common in this country (and still is in some). Maybe it’s a lost art that needs rediscovering.

Ipswich Yard now seems to be the only regular place for loco swaps. Freightliner did used to do some at Crewe on Southampton - Scotland runs. The most recent was GBRF with a 92 hauling a Dollands Moor to Irvine working as far as Carlisle, however this now appears to be a 66 throughout. The main driver will probably be loco usage, with Ipswich you have a couple of diesels shuttling between Ipswich and Felixstowe swapping with electrics which can run on to Trafford Park, Garston and Mossend so utilisation will be high. Other flows it becomes less economical to swap locos if there is nothing for the first to work until the return working of the service it arrived on - then you have two locos doing the work of one.

 

[superkev]

In Modern railways this month Ian Walmsley floats the idea of a twin loco, which would give room for all the bells and whistles (1 transformer, 1 engine/generator, 1 battery bank, 1 compressor, 1 brake frame) and save on 2 cabs compared with a 2 loco lash-up.
Pat

Interesting thought. The other day I was lookng at the spec of a Flirt dmu power house which is more powerful then a class 47 at 1,920 kW (2,570 hp). Perhaps theres some mileage in a similar solution. I.e. electric loco plus batter plus power house.
K

 

[JohnMcL7]

The Caledonian sleeper still swaps between electric and diesel traction at Edinburgh but as always with these discussions about bimode diesels I wonder at what point does the additional complexity make it worth it over just running a single standard diesel locomotive at least without any price incentives to use more electric traction.