Class 93 Tri-mode Loco

[themiller]

I don’t know if anyone’s zoomed in to the pictures of the 93 but it shows an auto-coupler. This ties in with the news item on www.railopsgroup.co.uk which says in an item regarding the acquisition of 57s from DRS in 2018 ‘The locomotives join ROGs existing class 37 and class 47 locomotives as the mainstay of ROG’s locomotive fleet provision and will remain so until the arrival of ROG’s new locomotive fleet.’ I take this as a statement that, once the 93s are accepted into service, older locos will be disposed of.

 

[MikePJ]

Will the batteries be able to provide peak shaving capability when operating on diesel? This will mean that heavy engine loads (ie getting moving on diesel, increases in speed etc) can be assisted by the batteries, thus reducing load and therefore emissions and consumption by the diesel prime mover.

Yes, that's exactly it. Quoting from the original press release: "The two LTO battery packs provide 400kW extra power to supplement the engine when the locomotive is running in diesel/battery hybrid mode as well as last mile carbon free shunting operation" - so that implies that the loco can be used in battery-only; battery+diesel; and overhead-electric modes. The 900kW diesel is supplemented by 400kW from batteries, meaning that 1300kW is available at full output (equivalent to a Class 37 - 1750hp is 1305kW). What isn't stated is the capacity of the battery packs, so we don't know how long it will be able to sustain that output. But I'd expect performance broadly equivalent to a type 3 locomotive - but with rather better fuel economy than any of existing type 3s!

 

[Richard Scott]

Yes, that's exactly it. Quoting from the original press release: "The two LTO battery packs provide 400kW extra power to supplement the engine when the locomotive is running in diesel/battery hybrid mode as well as last mile carbon free shunting operation" - so that implies that the loco can be used in battery-only; battery+diesel; and overhead-electric modes. The 900kW diesel is supplemented by 400kW from batteries, meaning that 1300kW is available at full output (equivalent to a Class 37 - 1750hp is 1305kW). What isn't stated is the capacity of the battery packs, so we don't know how long it will be able to sustain that output. But I'd expect performance broadly equivalent to a type 3 locomotive - but with rather better fuel economy than any of existing type 3s!

Don't forget that the battery output is available to the motors, a diesel engine output has to incur generation losses so likely it'll have much improved power over a 37 for as long as battery pack can supply power. Even 900kW with a three phase drive is going to have vastly superior performance to a 25, which is broadly similar in diesel power.

 

[hooverboy]

Yes, that's exactly it. Quoting from the original press release: "The two LTO battery packs provide 400kW extra power to supplement the engine when the locomotive is running in diesel/battery hybrid mode as well as last mile carbon free shunting operation" - so that implies that the loco can be used in battery-only; battery+diesel; and overhead-electric modes. The 900kW diesel is supplemented by 400kW from batteries, meaning that 1300kW is available at full output (equivalent to a Class 37 - 1750hp is 1305kW). What isn't stated is the capacity of the battery packs, so we don't know how long it will be able to sustain that output. But I'd expect performance broadly equivalent to a type 3 locomotive - but with rather better fuel economy than any of existing type 3s!

That being the case,the concept should work pretty well, but the cl37 still has the edge with lower axle load/more traction points and a shorter wheelbase than the proposed cl93.
RA7 or whatever cl93 turns out to be,assuming they are using the bogies and bodyshell of 68/88 will still have some restrictions on where it can go.They would be better off with a co-co bogie arrangement for starters.

That's the beauty of the cl20 and 37, they can pretty much go anywhere.

 

[ExRes]

That being the case,the concept should work pretty well, but the cl37 still has the edge with lower axle load/more traction points and a shorter wheelbase than the proposed cl93.
RA7 or whatever cl93 turns out to be,assuming they are using the bogies and bodyshell of 68/88 will still have some restrictions on where it can go.They would be better off with a co-co bogie arrangement for starters.

That's the beauty of the cl20 and 37, they can pretty much go anywhere.

A co-co class 20?

 

[hooverboy]

A co-co class 20?

not quite.

class 20 is bo-bo but at only something like 15m long, it can handle some seriously sharp radius curves,which is what makes it so useful.

class 37 is co-co and only 18m long+90 tonnes, so has the best of both worlds. Low axle load,powerful enough for most general duties..passenger and freight, and can also handle very sharp curves.Its probably the most versatile loco out of the entire mainline fleet.

 

[hooverboy]

not quite.

class 20 is bo-bo but at only something like 15m long, it can handle some seriously sharp radius curves,which is what makes it so useful.

class 37 is co-co and only 18m long+90 tonnes, so has the best of both worlds. Low axle load,powerful enough for most general duties..passenger and freight, and can also handle very sharp curves.Its probably the most versatile loco out of the entire mainline fleet.

perhaps colas are eyeing up back to back hst cabs as cl20 replacements, they are the only thing that comes close to 2*cl20 in terms of route clearance.

as for the 93's.I'm not quite sure the proposed spec is quite able to duplicate cl37's, but the bimode/hybrid capability is certainly a step in the right direction.

 

[Speed43125]

perhaps colas are eyeing up back to back hst cabs as cl20 replacements, they are the only thing that comes close to 2*cl20 in terms of route clearance.

as for the 93's.I'm not quite sure the proposed spec is quite able to duplicate cl37's, but the bimode/hybrid capability is certainly a step in the right direction.

They seem to think they'll be able to generate new liner flows with the green credentials of the operation, I've read?

 

[Richard Scott]

not quite.

class 20 is bo-bo but at only something like 15m long, it can handle some seriously sharp radius curves,which is what makes it so useful.

class 37 is co-co and only 18m long+90 tonnes, so has the best of both worlds. Low axle load,powerful enough for most general duties..passenger and freight, and can also handle very sharp curves.Its probably the most versatile loco out of the entire mainline fleet.

37s are around 105 tonnes.

 

[172007]

I am intrigued by how this will work off the wires. Battery with Diesal. I am guessing that the battery will be used to get the train moving, once upto speed and less power is required to maintain a given speed the Diesal engine will then recharge the batteries. Same would go for going down hill, coasting and also when stationary.

Really might be an elegant method of getting around the limitations of limited last mile Diesal power and being unable to fit a regular sized diesel engine into the UK loading gauge On a bi-mode.

 

[Richard Scott]

I am intrigued by how this will work off the wires. Battery with Diesal. I am guessing that the battery will be used to get the train moving, once upto speed and less power is required to maintain a given speed the Diesal engine will then recharge the batteries. Same would go for going down hill, coasting and also when stationary.

Really might be an elegant method of getting around the limitations of limited last mile Diesal power and being unable to fit a regular sized diesel engine into the UK loading gauge On a bi-mode.

Think the plan is loco can use battery power alone or batteries can be used to boost power in diesel mode so give better acceleration. Some of this energy can then be recovered when braking and recharge batteries to some degree. Whether diesel engine charges batteries on idle I don't know.

 

[172007]

Think the plan is loco can use battery power alone or batteries can be used to boost power in diesel mode so give better acceleration. Some of this energy can then be recovered when braking and recharge batteries to some degree. Whether diesel engine charges batteries on idle I don't know.

The press statement says it can use the Diesel to charge. I guess my question was that this may well operate as a perfectly equivalent to a class 37 away from the wires but with much better wheelslip protection with modern technology.

 

[LOL The Irony]

Finally, an ACTUAL Tri-Mode. I must say I prefer the 68/88 cab as this new one looks a bit boring and bland.

 

[Charlie Smythe]

Impressive concept, although there are a few things that of course haven't been answered.

The weight of the locomotive when fully fueled is important. I know the loco is RA7 which is the same as an 88, but this loco has a bigger engine and two batteries plus all the other equipment for those batteries that the 88 doesn't have. This makes me wonder if they have sacrificed a few things to keep the RA7 rating. One thing could be fuel capacity as you can save a few tonnes there. I hope it doesn't restrict this loco's diesel range as there are several workings that have a lot of diesel only working plus electric working that this loco would be good for.

 

[Richard Scott]

Impressive concept, although there are a few things that of course haven't been answered.

The weight of the locomotive when fully fueled is important. I know the loco is RA7 which is the same as an 88, but this loco has a bigger engine and two batteries plus all the other equipment for those batteries that the 88 doesn't have. This makes me wonder if they have sacrificed a few things to keep the RA7 rating. One thing could be fuel capacity as you can save a few tonnes there. I hope it doesn't restrict this loco's diesel range as there are several workings that have a lot of diesel only working plus electric working that this loco would be good for.

The engine is exactly the same weight as that in an 88, I looked up the spec and compared it when information was published. Be interesting to see how heavy the batteries are. Also engine is Stage V compliant, I believe, wouldn't be surprised if that comes with a weight penalty?

 

[squizzler]

Interestingly, Railcolor have started reporting on a so-called Stadler Euro9000 which is a 9kw Co-Co and a clean sheet design not to be confused with Continental EuroDual series of which the Class 93 is the British cousin:

• Electric mode: 9,000 kW – available for multi-system operations under 1.5kV DC, 3kV DC, 15kV AC , 25kV AC;
• Diesel mode: 1,900 kW – thanks to two diesel engines with an output of 950 kW each.

Unlike the EuroDiesel/Euro40001/EuroDual/Euro6000 family of locomotives, the powerful Euro9000 has been designed as an electric locomotive.

Basically, this ostensibly electric machine is twice the power of the class 93 on both diesel and electric with only 50% more axles, albeit it seems to be a bi-mode rather than tri mode. However only a fool would bet against Stadler having designed this platform with provision for tri-mode options.

 

[Richard Scott]

Interestingly, Railcolor have started reporting on a so-called Stadler Euro9000 which is a 9kw Co-Co and a clean sheet design not to be confused with Continental EuroDual series of which the Class 93 is the British cousin:


Basically, this ostensibly electric machine is twice the power of the class 93 on both diesel and electric with only 50% more axles, albeit it seems to be a bi-mode rather than tri mode. However only a fool would bet against Stadler having designed this platform with provision for tri-mode options.

9000kW under 1.5kV, without melting the overheads?!!!!

 

[squizzler]

That’s apparently where the diesel come in: in one of the articles it says the gennies can be added to the limited power available from DC electrification.

There is a lot of interesting stuff behind the paywall but I don’t want to quote at length because it’s an enthusiast run site rather than corporate media.

 

[Charlie Smythe]

The engine is exactly the same weight as that in an 88, I looked up the spec and compared it when information was published. Be interesting to see how heavy the batteries are. Also engine is Stage V compliant, I believe, wouldn't be surprised if that comes with a weight penalty?

Exaclty the same, really? I am of course not doubting your research, but I am just suprised. I would have thought that the equipment that is required to be Stage V compliant will add some weight, but only Stadler and CAT know the answer to that.

So The Anonymous Widower released a write up about the Class 93 and a small snipet of it was about the batteries and their capacity. Quote: "It has two Lithium Titanate Oxide liquid-cooled battery packs, which have a rapid charge and discharge rate. These each have a 40kWh capacity with a peak power of 200kW. Thus, whilst the train is accelerating, the Class 93 will have a peak power of 1,300kW for up to ten minutes, which is almost twice that of a Class 88 in diesel mode."

So 80kWh in total and the specific energy value is anywhere between 60 and 110 Wh/kg so using the best case scenario value of 110 Wh/kg I work that out to be 727kg in total (363.5kg per battery) which isn't a lot, however, don't forget this is the best case scenario and it could be mucu higher.

​

 

[supervc-10]

80kWh total? That's less than what you get in a Tesla Model S these days. Definitely sounds more like a temporary torque fill type situation to me. Think Prius rather than a range-extending EV like the BMW i3.

 

[Richard Scott]

Exaclty the same, really? I am of course not doubting your research, but I am just suprised. I would have thought that the equipment that is required to be Stage V compliant will add some weight, but only Stadler and CAT know the answer to that.

It is same weight, has a slightly longer stroke and bigger bore but assume same block, probably along the lines of car engines where one block is designed with a variety of capacities in mind within a certain range?

 

[Energy]

80kWh total? That's less than what you get in a Tesla Model S these days. Definitely sounds more like a temporary torque fill type situation to me. Think Prius rather than a range-extending EV like the BMW i3.

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

 

[Greybeard33]

I think it is over-optimistic to imagine that the 93 will be suitable for freight haulage on an unelectrified main line. Those little batteries will give a few minutes boost to help get the train moving or climb a short bank, but then the diesel will be on its own. Its power output is only 36% of that of the 66's engine.

 

[Richard Scott]

I think it is over-optimistic to imagine that the 93 will be suitable for freight haulage on an unelectrified main line. Those little batteries will give a few minutes boost to help get the train moving or climb a short bank, but then the diesel will be on its own. Its power output is only 36% of that of the 66's engine.

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. Would be prolonged gradients that likely to cause an issue. Power at rail likely to better a 25 and they used to be entrusted to reasonable loads.

 

[Charlie Smythe]

80kWh total? That's less than what you get in a Tesla Model S these days. Definitely sounds more like a temporary torque fill type situation to me. Think Prius rather than a range-extending EV like the BMW i3.

I agree, it is definitley a boost to get the loco out of the yard/station and to assist the loco when travelling up a gradient. For example, if it was used for the Night Riviera (which people have been on about for literal years) then the diesel power would probably be okay for all of the journey other than on the South Devon Banks where it would quite possibly stall. We're a long way off having a tri-mode loco with battery power that can haul 2000+ tonne trains away from OHLE. The technology is there, but it's the space issue that is preventing it from becoming a reality.

It is same weight, has a slightly longer stroke and bigger bore but assume same block, probably along the lines of car engines where one block is designed with a variety of capacities in mind within a certain range?

That would explain why the CAT 32 was selected then. Why wouldn't it be if they can get more power from an engine that weighs the same and has similiar parts both made by CAT. As for the similarities with automotive engines, I think Ford does a similiar thing with their EcoBoost line of engines as well as their EcoBlue engines, although I could be wrong so don't quote me on that.

 

[hooverboy]

I think it is over-optimistic to imagine that the 93 will be suitable for freight haulage on an unelectrified main line. Those little batteries will give a few minutes boost to help get the train moving or climb a short bank, but then the diesel will be on its own. Its power output is only 36% of that of the 66's engine.

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.

 

[hooverboy]

I don't think the 110mph spec is really necessary,100mph is ample.Considering if it is to be used on passenger duties,it will more likely than not be rostered on charter trains and branch lines as cover for broken down or shortages of DMU's/EMU's, much like the DRS 37/47/68's did for greater anglia on norwich-yarmouth

 

[themiller]

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.

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.

 

[hooverboy]

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.

Granted the alternator on the genset is going to be bigger, however another avenue under development is the use of things like gallium nitride(and some other gallium doping derivatives) in power electronics and semiconductors instead of silicon.This has benefits in reducing the power dissipted in rectification gear and so on, so less space taken up by heatsinks and cooling solutions for these.

 

[hooverboy]

Granted the alternator on the genset is going to be bigger, however another avenue under development is the use of things like gallium nitride(and some other gallium doping derivatives) in power electronics and semiconductors instead of silicon.This has benefits in reducing the power dissipted in rectification gear and so on, so less space taken up by heatsinks and cooling solutions for these.

Anyway,it's good to see that some thought is finally being given to replacement of the 37/47 stalwart workhorses that have served the railway so well.at nearly 60 years old they have earned their retirement.