Electrification of freight traffic

[whole diary]

[grahame]

A "High level" question about electric freight haulage on UK^▸ (United Kingdom) railways - triggered by an article in Railway Gazette

UK: As part of its strategy to decarbonise rail freight and operate longer trains, Freightliner has acquired another 13 Class 90 electric locomotives formerly used on Greater Anglia inter-city services, bringing its fleet to 23.

Purchased from Porterbrook, the locomotives are being modified and refurbished ahead of their use on intermodal trains. Speaking during the launch of the first locomotive at Freightliner’s Vehicle Maintenance Facility in Crewe on July 30, Genesee & Wyoming’s CEO^▸ (Chief Executive Officer) for its UK/Europe Region companies Gary Long told Rail Business UK that the additional Class 90s were ‘an investment in the future’.

Confirming Freightliner’s aspiration to see much more freight transferring to rail, Long said ‘modal shift from road to rail is a purpose that we are constantly committed to. Being carbon neutral by 2030 would be spectacular for the whole industry and we’re making a commitment to that right now.’

[snip]

Shakerley [G&W European Engineering Director Tim Shakerley] said Freightliner was ‘really keen to support’ infill electrification between major passenger routes to create an electrified freight network, as ‘acquisition of the Class 90s pushes our electric fleet into the future. It enables us to haul freight up and down the network using electric traction, which is as close to carbon zero as we can get’.

What proportion of freight is electric hauled on the UK network at present?

How does electric haulage work when loading/unloading containers or stone?

Where is the infill needed?  `

Scope for more bimode for freight?

I'm coming from real basics on this one - "ask a silly question" day, but really "ask a newbie question set that is far from silly".  Anyone help me by addressing it?

[Robin Summerhill]

I can’t give you percentages but conversations with others suggest the amount of rail-borne freight in the UK^▸ (United Kingdom) is quite low compared to many other countries. One of the reasons for this is the relatively short distances much of it travels.

Having observed the number of diesel hauled freight under the wires, however, I have thought for some time that perhaps a way needs to be devised to use bi-modal locomotives. As this hasn’t been done already, when so much bi-modal passenger stock exists, leads me to the conclusion that it isn’t an easy thing to do.

Does perhaps the heavier loading of freight trains have something to do with it?

[paul7575]

There isn’t enough physical space in a normal GB^▸ (Great Britain) gauge loco to include a big enough Diesel engine and generator along with all the electrical stuff you’d need anyway, including a pretty massive transformer.

This is why the class 88 only has short range slow speed diesel capability, what’s known as a “last mile diesel”.

Maybe they could do it in a lengthened but articulated loco, perhaps with three bogies...

Paul

[stuving]

There isn’t enough physical space in a normal GB^▸ (Great Britain) gauge loco to include a big enough Diesel engine and generator along with all the electrical stuff you’d need anyway, including a pretty massive transformer.

This is why the class 88 only has short range slow speed diesel capability, what’s known as a “last mile diesel”.

Maybe they could do it in a lengthened but articulated loco, perhaps with three bogies...

Paul

It's a bit different the other way round. If you build a powerful electric loco, and the available supply and motor ratings allow that to be a lot more powerful than a diesel, it's too light to give the adhesion you need. You can avoid the lightweight bits used on passenger trains, and older heavier designs may well be more efficient, but it's still hard to get enough weight. So you may as well put in a small diesel - it's a better selling point than a lump of concrete. But it is still only a small diesel.

I'm not sure at what point axle loading becomes the factor that limits the worthwhile power. After all, big four-axle wagons have high axle loads anyway. But I have wondered if it makes more sense to use locos in pairs, either permanently coupled (allowing sharing of electric and diesel bits) or not (and of one or two kinds). Of course in much of the world, where freight trains are very much longer and heavier, multiple locos is the norm.

[broadgage]

One problem is that docksides and other freight terminals often can not be readily electrified due to the presence of cranes, gantries, and overhead conveyers.
Attaching a diesel engine for such circumstances finds little favour as cost, complexity and risks of delay are increased.

A hybrid locomotive that is primarily 25 Kv powered but with limited battery or diesel power would seem advantageous. A few hundred horsepower of diesel should be able to move the same weight as several thousand horsepower of electric power, but only at very low speeds. (at low speeds the limit is adhesion, not installed power)

Another more radical suggestion is to permanently couple together a diesel and an electric locomotive, forming in effect a single articulated bi-mode loco.
This would not be a simple case of multiple operation, but both units would be modified to improve performance.

In diesel mode, the diesel unit would provide traction power to the motors in the electric unit. At low speeds or when starting, this would roughly double the tractive effort due to more weight carried on motored axles.

In electric mode, the electric unit would power the motors in the diesel unit, thereby again increasing low speed tractive effort. If the existing transformer in the electric unit can be uprated (forced cooling ?) or replaced by a larger capacity transformer, then the total continuous power output can be increased. No uprating of traction motors required as the total power is now spread between the motors in both units.
In electric mode, auxiliary power would be supplied to the diesel unit so as to keep the engine warm, the batteries fully charged, and heat or air condition the drivers cab.

A traction current jumper would be required between the two units, and the inner cabs taken out of use, or even removed.
A trial could be conducted making use of existing locomotives. If successful then new build bi-mode articulated units could be built. For main line use I suspect that an articulated design would be required, I doubt that a single locomotive of acceptable weight and length could incorporate both diesel and electric equipment of sufficient power for heavy trains at 60MPH or more.

For very low speed operation, a small diesel engine could probably be added to an existing design of electric locomotive.

[eightonedee]

The following (ill informed?) thoughts-

1 - What is the usual weight of container trains? I am familiar with the long mineral trains running past me at Reading with their gross and tare weights marked on each wagon. Could electric locos cope perfectly adequately with them, or are they still heavy enough to cause adhesion problems?

2 - What would be the impact of splitting the current long heavy and relatively slow diesel hauled trains and replacing them with more frequent faster but shorter electric trains?

3 - If Freightliner can persuade NR^» (Network Rail - home page) to infill gaps - perhaps from Felixstowe to Birmingham, Southampton to Birmingham and connections to Immingham and the Trent Valley could all be on the list, this would benefit others as well (dream on?)

4 - And if it does all happen, there will be plenty of redundant class 66s to propel the containers under the cranes to and from the docks without OHL^▸ (Over-Head Line).

[onthecushions]

Glad to see at least 23 class 90's might have a future.

If I were FL, I would look at a new build of an unpowered vehicle like:

http://www.rvp-ltd.org.uk/projectx/

and commission a design for fitting it with an MTU^▸ (Motor Traction Unit) diesel alternator set (or two!), common to other units such as the 802's, with a SR^‡(resolve) style power train line connection to the locomotive.

The Brake Tender profile is low enough for sufficient view ahead, so wouldn't need running round..

However, I wouldn't inflict an IEP^▸ (Intercity Express Program / Project.) seat on the driver!

Just a thought in lock-down.

OTC

[Electric train]

The following (ill informed?) thoughts-

1 - What is the usual weight of container trains? I am familiar with the long mineral trains running past me at Reading with their gross and tare weights marked on each wagon. Could electric locos cope perfectly adequately with them, or are they still heavy enough to cause adhesion problems?

2 - What would be the impact of splitting the current long heavy and relatively slow diesel hauled trains and replacing them with more frequent faster but shorter electric trains?

3 - If Freightliner can persuade NR^» (Network Rail - home page) to infill gaps - perhaps from Felixstowe to Birmingham, Southampton to Birmingham and connections to Immingham and the Trent Valley could all be on the list, this would benefit others as well (dream on?)

4 - And if it does all happen, there will be plenty of redundant class 66s to propel the containers under the cranes to and from the docks without OHL^▸ (Over-Head Line).

1 - You can make electric locos as heavy as you need, the addition of concrete ballast weights, however its unlikely needed; modern 3 phase A/C traction motors and power control allows electric locos to haul heavy freight.  The limitation is the max current than can be drawn from the OLE^▸ (Overhead Line Equipment, more often "OHLE").  There are some issues on the WCML^▸ (West Coast Main Line) North of Preston and over the boarder with circuit breaker tripping's due to the double headed 90's
The UK^▸ (United Kingdom) operates a mixed traffic railway, and has done for over a centaury, this a compromise between the need for high speed over heavy freight.

2 - efference the FoC wants to put a traction unit on the head of the train that will do the entire trip with as few crew changes as possible, so a diesel loco for a Scotland to Dollands Moor trip can make more sense to them than uncoupling and coupling locos at Wembley

3 - UK PLC or should I say UK Government need to decide that is where it wants to spend UK tax payers money, NR does not fund enhancements it would be up to the FoCs to make the case to DfT^» (Department for Transport - about) which I am sure NR would support, the ToCs would need to buy into it as well local Authorities and business along the entire route especially if the electrification work leads to disruption, noise etc where there is no local benefit 

[rogerw]

2 - efference the FoC wants to put a traction unit on the head of the train that will do the entire trip with as few crew changes as possible, so a diesel loco for a Scotland to Dollands Moor trip can make more sense to them than uncoupling and coupling locos at Wembley

I thought that was what the Cl92 were for. To avoid the change at Wembley

[onthecushions]

What proportion of freight is electric hauled on the UK^▸ (United Kingdom) network at present?

How does electric haulage work when loading/unloading containers or stone?

Where is the infill needed?  `

Scope for more bimode for freight?

I'm coming from real basics on this one - "ask a silly question" day, but really "ask a newbie question set that is far from silly".  Anyone help me by addressing it?

Perhaps the link below might help. Figure 2.1 in Section 2, p 17, gives a map of the required network. P19 gives a road/rail comparison. P 20 gives total annual movements.

Thanks for Tuesday, Grahame, and our splendid companions.

OTC


https://www.networkrail.co.uk/wp-content/uploads/2017/04/Freight-Network-Study-April-2017.pdf

[eightf48544]

Perhaps some infill electrifiction around London such as:

Acton - Acton Wells
Acton Wells - Mitre Bridge Jn/WCML^▸ (West Coast Main Line)
Acton Wells - Cricklewood (Neasden?)
Acton Canal Wharf - WCML
Carlton Road Jn - Junction Rd Jn
Is spur to RCML electrified?

Kew Triangle from NL - Hounslow Loop (Class 92s)

[Electric train]

2 - efference the FoC wants to put a traction unit on the head of the train that will do the entire trip with as few crew changes as possible, so a diesel loco for a Scotland to Dollands Moor trip can make more sense to them than uncoupling and coupling locos at Wembley

I thought that was what the Cl92 were for. To avoid the change at Wembley

They were, not fully utilised as there are limited routes in Kent they can be used on due to the high current.

[onthecushions]

I think that the problem is in the specification of the class 92. 4MW off the third rail!

What might have been done is to provide emulator software like the class 91's (they can pretend to be any of the class 8X's!) so that they could substitute easily. If a 92 could pretend to be one or perhaps two 73's at most....

There's something called conductor line index, basically one unit per EE507 /185kW motor, so a 12 car unit = 12 (a REP consist = 14), a 73 = 8. The maximum allowed was 16 - a 92 powering would be over 32!

Perhaps there turned out to be too little freight to bother.

OTC

[Electric train]

I think that the problem is in the specification of the class 92. 4MW off the third rail!

What might have been done is to provide emulator software like the class 91's (they can pretend to be any of the class 8X's!) so that they could substitute easily. If a 92 could pretend to be one or perhaps two 73's at most....

There's something called conductor line index, basically one unit per EE507 /185kW motor, so a 12 car unit = 12 (a REP consist = 14), a 73 = 8. The maximum allowed was 16 - a 92 powering would be over 32!

Perhaps there turned out to be too little freight to bother.

OTC

Basically yes.

There are areas in the Southern where double head 73 on third rail is not permitted.

The typical route setting (DC^▸ (Direct Current) Protection setting) is for 4kA (3MW) High current railway can go to 6kA (4.5MW) the former Eurostar routes are high current railways.

High current railway needs to have 4kA rated circuit breakers with impedance protection the old falling voltage protection is not adequate, the track feeder cables need to be doubled to two 1000mm sq aluminium cables and the hook switches removed.  The rectifiers also need uprating to 3.5MW class G

There are still a lot of the older 2.5kA rated DC circuit breakers on the network these in the most part are ok at 4kA route setting

[ellendune]

I think that the problem is in the specification of the class 92. 4MW off the third rail!

What might have been done is to provide emulator software like the class 91's (they can pretend to be any of the class 8X's!) so that they could substitute easily. If a 92 could pretend to be one or perhaps two 73's at most....

There's something called conductor line index, basically one unit per EE507 /185kW motor, so a 12 car unit = 12 (a REP consist = 14), a 73 = 8. The maximum allowed was 16 - a 92 powering would be over 32!

Perhaps there turned out to be too little freight to bother.

OTC

Basically yes.

There are areas in the Southern where double head 73 on third rail is not permitted.

The typical route setting (DC^▸ (Direct Current) Protection setting) is for 4kA (3MW) High current railway can go to 6kA (4.5MW) the former Eurostar routes are high current railways.

High current railway needs to have 4kA rated circuit breakers with impedance protection the old falling voltage protection is not adequate, the track feeder cables need to be doubled to two 1000mm sq aluminium cables and the hook switches removed.  The rectifiers also need uprating to 3.5MW class G

There are still a lot of the older 2.5kA rated DC circuit breakers on the network these in the most part are ok at 4kA route setting

You can see why people think 25kV OLE^▸ (Overhead Line Equipment, more often "OHLE") is the future