The Anonymous Widower

Do Bombardier Aventras Have Remote Wake-Up?

Remote wake-up is detailed in this snippet from an article in the Derby Telegraph, which appears to have since been deleted.

Unlike today’s commuter trains, Aventra can shut down fully at night and can be “woken up” by remote control before the driver arrives for the first shift.

So could we see a train parked up at night in the sidings at the end of the line, after forming the last train from London? The train would then call home and report any problems, which would be sorted if needed, by perhaps a local or mobile servicing team. In the morning, the driver would turn up and find that the train was warm and ready to form the first train of the day up to London.

Since I found this in 2016, I’ve told several drivers and all had stories about cold trains in their least favourite places.

September 10, 2017 Posted by | Transport/Travel | , , | 14 Comments

Small Electrification Projects

My visit to Abbey Wood station yestetday proved to me that some small electrification projects don’t actually need wires or third rails.

The reversing siding for Crossrail, which is also a link to the North Kent Line, consists of the following new tracks.

  1. A set of points at the Eastern end of Abbey Wood Station to connect the two Crossrail platforms 3 and 4 and allow trains to reverse.
  2. A track to serve as the reversing siding and the link between the two lines. It is probably about 700 metres long.
  3. A set of points to connect the libk to the Down North Kent Line.
  4. A cross-over between the two North Kent Lines.

Only about  fifty metres of the reversing siding around the first set of points is electrified.

I have been convinced for some time, that the Barking Riversude Extension will be built without wires, as the project details mention electric trains, but don’t mention electrification.

Aventras may also have a remote wake-up capability as detailed in Do Bombardier Aventras Have Remote Wake-Up?, which would allow trains to be parked overnight in sidings without electrification

July 11, 2017 Posted by | Transport/Travel | , , | Leave a comment

Gibb Report – Cambridge Depot

The Gibb Report, looks in detail at GTR’s depot capacity and especially the stabling for Thameslink.

The report indicates particular problems at Cambridge.

The facility is currently unsuitable for 12 car fixed formation trains and the current trains have to be uncoupled to be accommodated.

Greater Anglia will have the following trains at Cambridge in their open-air depot.

All trains are fixed-formation and I suspect that Greater Anglia have a well-planned train parking philosophy, which could include.

  • Parking two five-car Aventras in a long ten/twelve-car siding.
  • Remote wake-up for the Class 720 and Class 745 trains as I discussed in Do Bombardier Aventras Have Remote Wake-Up?
  • Parking the odd Class 755 train, that will work services to Ipswich in one of the bay platforms.
  • Parking the Class 755 trains, that will work Norwich to Stansted, at the ends of the route.
  • Having a remote toilet servicing team for their trains.

But it would be difficult to fit in the following two trains per hour (tph) Thameslink services.

  • Cambridge to Brighton – Twelve-car Class 700 train
  • Cambridge to Maidstone East – Eight-car Class 700 train

Both services would be run all day, with journey times in excess of two hours, which probably means each service would need nine or ten trains.

GTR will have a need for their own depot as mixing eight and twelve car trains will just fill up Greater Anglia’s depot and I doubt they will be pleased.

The problem can’t be eased by running twelve-car trains to Maidstone East, as the Thameslink platform at that station is too short.

Although Maidstone East station may be redeveloped in the future and a twelve-car platform 3 could be incorporated.

This Google Map shows the layout of Maidstone East station.

Could a twelve-car pltform be squeezed in?

Six-car as opposed to eight-car trains may offer an alternative solution here.

Cambridge would be served by a twelve-car train, that was formed of two six-car units coupled together.

At Bromley South or Swanley station, the two trains would split, with one portion going to Maidstone East station and the other to another convenient station.

Returning North the trains would join up again and travel to Cambridge as a twelve-car train.

The advantages of this are as follows.

  • Two eight-car tph in the core are replaced by twelve-car trains.
  • Two eight-car Cambridge to London tph are replaced by twelve-car trains.
  • Another destination South of London gets awo six-car tph to Cambridge.

The only loser is Maidstone East station, which sees the train length of its two trains per hour to Cambridge reduced from eight-cars to six.

July 9, 2017 Posted by | Transport/Travel | , , , , , | 3 Comments

Gibb Report – Depot Issues

The Gibb Report, looks in detail at GTR’s depot capacity and especially the stabling for Thameslink.

The section on depots starts like this.

The way in which the train fleet has expanded in recent years has resulted in a shortage of stabling facilities. New facilities have been located away from train crew depots (e.g. Hove from Brighton) and are less efficient, involving driver time in taxis. Siemens new depot at Three Bridges is now the main centre for the Thameslink fleet, and overall the depot capacity on Southern is just about sufficient from what I have seen, although it is inflexible and inefficient.

It then goes on to list problems at specific locations.


Perhaps the late choice of Maidstone East station, as a terminus, has meant that a site hasn’t really been found for a depot at Ashford.


The depot is unsuitable for 12-car fixed formation Class 700 trains, which block the entrance.


The facility is currently unsuitable for 12 car fixed formation trains and the current trains have to be uncoupled to be accommodated.

North Kent

The original plan was to increase stabling facilities at Slade Green, but this has now been established to cost £72m and too expensive. An alternative is urgently needed.

The report sums up the depot issues like this.

All of the above issues need to be finalised before the driver recruitment plans can be commenced, as the driver recruitment strategy must be decided around the stabling locations of the trains, and driver depot facilities, including parking, must be included in the scheme

It also goes on to say, that more trains may need to be ordered to increase capacity on the Brighton Main Line and that a new depot will be needed.

Bombardier’s Class 345 Trains For Crossrail

Before I add my fourpennyworth on depot issues, I will look at some of the features of Bombardier’s Class 345 trains.

All Trains Are The Same Length

It is intended that all trains will be the same nine-car length, although at the present time, the trains under test in East London are a couple of cars short of a full train.

This is mainly because the platforms in Liverpool Street, are not long enough for a full train and won’t be lengthened until a year or so.

I suspect too, it enables Bombardier to build the trains in a more efficient manner and test out each type of coach fully.

One of the advantages in having all trains of the same length, is that you maximise the capacity in a depot and as on both routes, the manufacturer pays for the main depots, a correctly-sized depot will reduce costs.

Note that Thameslink’s main depots don’t seem to have issues, so can we assume they were well-designed?

The Class 345 Trains Have No Toilets

There was a bit of a fuss, when this was announced, as I wrote about  in Do Crossrail Trains Need Toilets?.

But given that many Crossrail stations have toilets on the platforms and trains are every ten minutes, no toilets on the train gives advantages.

  • There is no toilet on the train that needs regular cleaning and fails occasionally.
  • Overnight servicing of the train does not need the toilet to be emptied.

I also suspect that the modular nature of the Class 345 train would allow one to be fitted if required.

Class 345 Trains Are Designed For Remote Wake-Up

Remote wake-up is discussed in Do Bombardier Aventras Have Remote Wake-Up?.

So imagine a Class 345 train finishes its last journey of the day in a platform at Shenfield station or a convenient stabling siding.

  • The driver checks the train for sleeping bankers, locks up and goes home.
  • The train reports to Ilford, that a couple of light bulbs have failed.
  • The servicing and cleaning team arrive and get the train pristine for the morning.
  • The train shuts down fully and all power is switched off to the overhead wires, so trespassers won’t be electrocuted.
  • At an appropriate time, the train is signalled to come to life and warms up ready for the day, using battery power.
  • The driver arrives and when signalled joins the main line, raises the pantograph and takes the train on its way.

When I once described this process to a driver from Northern going to pick up a Class 156 train in Halifax, he had a big smile.

In some ways, it’s a bit like parking your car out on the street.

  • Except that for trains, you need a convenient piece of track.
  • As power will be needed to warm the train up in the morning and you don’t want 25 KVAC  live wires about, the only source of power possible is a battery.
  • If the train had a toilet, it would be a more complicated process.

What will the devious Derbians think of next?

Solving GTR’s Depot Problems

In my view there is one big difference between Thameslink and Crossrail.

With Crossrail, which was in part a new railway line, every component was designed so it fitted together like a giant three-dimensional jigsaw.

But Thameslink was designed by different teams over a series of decades.

As we can’t go back to square one on Thameslink we have to make the best of what we’ve been left with.

Bombardier’s remote wake-up concept is a straight steal from some upmarket road vehicles, so why haven’t Siemens stolen it? Especially, as the Derby Telegraph article dates from June 2011. Perhaps, their press cuttings agency doesn’t read that newspaper?

If they had developed the technology, it would certainly help with remote stabling of trains, as you can have a much simpler facility.

The Problem Of Cambridge

I discuss this in Cambridge Depot

The Problem Of North Kent

Chris Gibb suggest creating a new depot at Hoo Junction, which I discuss in Hoo Junction Depot

Thameslink’s Mixed Length Fleet

Thameslink also have a curious mix of eight-car and twelve-car trains, whereas Crossrail have sensibly opted for a common length, which as I said, must be much easier to store.

Intriguingly, both Greater Anglia and South Western Railway have ordered mixed fleets of five and ten-car Aventras. But most six-year-olds can tell you that 5+5=10.

The decision to buy a mixed length fleet of twelve and eight-car trains for Thameslink has caused a lot of these depot and a few other problems.

I wrote more about the problem in Has Thameslink Got The Wrong Length Of Train?.

I think in the end, Thameslink will lengthen the eight-car trains to twelve-cars and then lengthen the short platforms on the Sutton loop Line and a few other places.

This would create sixteen per-cent more capacity through the central tunnel, by making all trains twelve-cars.

But that is an expensive way to solve the problem created by not designing Thameslink as a continuous twelve-car railway.


It’s a bloody-great mess.

If you compare depot philosophies at  Crossrail, Greater Anglia and Thameslink, the first two companies seem to have developed a comprehensive purchase and maintenance solution for all their new trains, whereas Thameslink have worked on the basis that it will be alright in the end.

These factors don’t help Thameslink.

  • The choice of a mix of eight- and twelve-car trains.
  • The inability to join two short trains together to make a long train.
  • The design of a Class 700 train, which appears to be geared more towards a traditional depot.

I will be accused of being patriotic, but having ridden in both Class 700 and Class 345 trains, I’m coming to the conclusion, that Thameslink should have bought Aventras.

I would also have to ask, if Krefeld in Germany is a better place than Derby, for decision makers to visit.

July 8, 2017 Posted by | Transport/Travel | , , , , , , , | 1 Comment

Bi-Mode Ate My Electrification

The title of this post,  is the headline on an article by Roger Ford in the January 2017 Edition of Modern Railways.

The article describes how electrification of the rail line between Selby and Hull has been dropped and quotes Chris Grayling as implying  that it’s all because the train companies have bought Class 802 trains, which are bi-mode, and won’t need electrification between Selby and Hull.

Both train companies; Hull Trains and TransPennine Express need to run high-class services with modern fast trains to Hull.

I will look at Hull Trains need in more detail.

Much of the route used by Hull Trains is along the electrified East Coast Main Line, so a 140 mph capability could be needed in the next few years, as speeds increase on that line.

If the Selby-Hull line were to be electrified, Hull Trains could run electric trains like Class 801 trains, InterCity 225s, or perhaps a version of the Stadler Flirt, that Greater Anglia will be running.

Hull Trains obviously need to increase quality and capacity on the route and it appears that the only train available is the bi-mode Class 802 train.

The only certain way Hull Trains could get new trains in a reasonable time, given that electrification is continually being kicked into the long grass,  is the bi-mode route.

Purists might not like the bi-mode train, but at least it will enable Hull to have a quality high-speed train service.

The Problems With Electrification

Electrification is needed, so that trains can run fast and efficiently, without the noise, pollution and carbon-emissions of diesel power.


  • Electrification in the UK, is like trying to make a Victorian house fit for a modern lifestyle and it is even more expensive.
  • Electrification gantries and wires, ruin landscapes.
  • Much of our railway infrastructure,like stations, bridges and viaducts are beautiful structures in their own right and perhaps electrification will not be for some of them.

As we get further into the future, I think that there will be more reasons why existing lines will not be electrified.

We’re All In It Together

Several countries have a substantial proportion of lines without electrification, of which Germany, India and, the UK and the US are the most notable examples.

So ideas will be developed in these and other countries, that could be replicated in other countries with a pressing need for electrification.

The Problem Is An Opportunity For The Train Builders


  • Hitachi have developed their Class 800 family of trains to include bi-modes.
  • Bombardier are developing trains with onboard electric storage and have a philosophy for all markets that I wrote iabout in Parallel Thinking From Bombardier.
  • Stadler have a Pandora’s box for of ideas and technologies.
  • CAF are supplying trams with onboard energy storage.

I can’t believe that Alstom, Siemens and other fFar Eastern manufacturers are not looking at using self-powered trains to cut down on electrification.

It is also worth noting that others are developing technologies, that will assist train builders in providing the trains that train companies and their passengers desire.

  • Tessla and other companies are developing batteries with a higher storage density.
  • Automatic pantograph up and down is being developed, so trains can use overhead power, where it exists.
  • Automatic coupling and uncoupling will be developed.
  • Trains will be driven automatically, so minimum power is used.

The train of the future will be powered and braked by electricity, and highly automated. It could be driven automatically, but I suspect like the Victoria Line or your average commercial airliner, the driver will be in overall control and  monitoring everything.

Why Trains Need An Energy Storage Capability?

If an electric train has an onboard energy storage capability, it has various advantages.

  • It can store the energy generated from regenerative braking and release it to help get the train back up to speed.
  • On board energy storage can be used with both electric and diesel-electric trains.
  • Depots can be designed with less electrification for safety and to save money.
  • Trains can be given a remote wake-up capability as I discussed in Do Bombardier Aventras Have Remote Wake-Up?, so a train parked in a siding can be warmed up ready for the driver at the start of the day.
  • Trains can recover to the next station using stored power, if electrification power fails.
  • Trains can take diversions without electrification if needed.
  • Depending on the size of the storage, trains could provide a service over a limited distance on stored power alone.

Hybrid cars and buses, which have onboard energy storage,  might suggest even more reasons.

Energy Storage Can Only Get Better

Over the last few decades the energy capable of being stored in a device of a fixed physical size and weight has increased dramatically.

This process can only increase, so onboard energy storage will become more and more viable.

What Is The Kinetic Energy Of A Train?

I ask this question to show the energy values involved.

If I take a nine-car Class 345 train, which will be used on Crossrail, this has a mass of less than 350 tonnes and a maximum speed of 145 kph.

1500 passengers at 80 kg each works out at another 120 tonnes.

So for this crude estimate I’ll use 450 tonnes for the mass of a loaded train.

This gives the train an energy of 365 megajoules or 101 kilowatt-hours.

This amount of energy is only a couple of kWh larger than the largest battery size of a Tessla Model S car.

Can Regenerative Braking Be Handled By Onboard Energy Storage On A Train?

As an example, look at the Stadler Flirts and Bombardier Aventras, that will be running between London Liverpool Street and Cambridge, Colchester, Ipswich, Norwich, Southend and Stansted Airport.

  • These are fully-electrified lines.
  • The ability to stop and restart quickly is needed as these are very busy lines, with another 110 mph train along in a couple of minutes.
  • All the passenger trains on the lines will have regenerative braking.

The electricity generated by braking can either be returned to the overhead wires using an inverter to get the voltages right or stored on the train in an onboard energy storage device.

Both methods are possible with good electrical engineering and there is probably no weight or installation advantage with either technology.

I don’t know what Stadler are doing, but this article in Global Rail News from 2011, which is entitled Bombardier’s AVENTRA – A new era in train performance, gives some details of the Aventra’s electrical systems. This is said.

AVENTRA can run on both 25kV AC and 750V DC power – the high-efficiency transformers being another area where a heavier component was chosen because, in the long term, it’s cheaper to run. Pairs of cars will run off a common power bus with a converter on one car powering both. The other car can be fitted with power storage devices such as super-capacitors or Lithium-Iron batteries if required.

As this was published five years ago, I can’t believe that an innovative company like Stadler have not been thinking about onboard electrical storage.

As I showed in the previous section, the kinetic energy of a Crossrail Class 345 train is around 101 kiowatt-hours.

So it is not beyond the bounds of possibility that a couple of Tessla batteries could handle the regenerative braking for a fully-loaded Crossrail train!

The same would apply to all of the trains  in East Anglia, which would probably have a bit more kinetic energy.

It can obviously be done on an Aventra, so I feel that the Flirts will do it as well.

If all the trains on the routes handled their own regenerative braking, this could mean that there would be no need for the power supply to the overhead wires to be able to handle it. Whether that would save money, I don’t know!

Can the same technology be applied to a locomotive-hauled train, like a Class 68 locomotive pulling a rake of five Mark 3 coaches at 160 kph?

The kinetic energy is slightly less than that of the Crossrail train, so it might be feasible to put onboard energy storage in the diesel-electric locomotive to reuse braking energy.

Onboard energy storage for regenerative braking will become universal on all electric or diesel-electric trains.

In March 2016, I wrote Will London Overground Fit On-board Energy Storage To Class 378 Trains?, which was based on this article in Rail Technology Magazine entitled Bombardier enters key analysis phase of IPEMU. In the article, Marc Phillips of Bombardier is quoted as saying this.

All Electrostars to some degree can be retrofitted with batteries. We are talking the newer generation EMU as well as the older generation. So, the 387s and 378s are the ones where we have re-gen braking where we can top-up the batteries and use the braking energy to charge the batteries. That gives us the best cost-benefit over operational life.

So it would seem that the Class 378 trains of the London Overground are candidates for fitting with batteries. This would give the following advantages.

  • Electricity savings.
  • Recovery to the next station if the electricity supply fails.
  • Simplified depot layouts with less electrification.

As nearly all lines are electrified in London, the ability to travel on short routes without electrification wouldn’t be needed.

On the other hand, new services might need a new branch line or a chord between two electrified lines, which if worked with trains with onboard energy storage, would not need to be electrified.

In Don’t Mention Electrification!, I noted that in all the documents for the extension of the Gospel Oak to Barking Line to Barking Riverside, there is no mention of electrification, although electric trains are stated to be working the route.

So could this be the first newly-built line in the UK to be worked by electric trains powered by onboard energy storage?

How Far Will Trains Go On Onboard Energy Storage?

This is very much a case of answering these and other questions.

  • How much range do you want?
  • Does the route have lots of stops?
  • Is the route hilly?
  • How much space there is on the train?

In the end, the most important question is can you afford it?

Could We See A Tri-Mode Train?

A tri-mode train would be one that could use the following power sources.

  • Electric power from either 25 KVAC overhead or 750 VDC third-rail.
  • Diesel power.
  • Onboard energy storage.

It could even pick up 750 VDC from a tramway, if it was running as a train-tram.


  • If you look at an Hitachi Class 800 train, I suspect that the engineers could find space somewhere for onboard energy storage.
  • The Aventra double-power-car concept, has probably been designed with a diesel version in mind.
  • A hydrogen fuel-cell would be an alternative to diesel.
  • The power control system would just switch between power sources automatically.

It’s all down to good engineering design and innovation.

I suspect, that a tri-mode train will be launched in the next few years.


I believe there is a lot of scope to cut the amount of electrification that is done, by using alternative technologies.

The bi-mode is in pole position, but with the advance of battery and other technologies, the current lead will not last long.



December 22, 2016 Posted by | Transport/Travel | , , | 1 Comment

Parallel Thinking From Bombardier

Bombardier’s New Talent 3 Electrical Multiuple Unit

This is the data sheet on Bombardier’s web site announcing the new Talent 3 EMU, which has recently been announced at Innotrans 2016. It is the successor to the Talent 2.

These are some phrases picked from the sheet.

  • Flexible and efficient when operating as commuter, regional, or intercity train.
  • The use of proven and optimized components, recognized in operation in several European countries,
  • For the first time a TALENT EMU train is compatible with the BOMBARDIER PRIMOVE Li-ion battery system.

Reading the data sheet the train seems very similar to the Aventra, except that in the case of the Talent 3, they mention batteries.


This Bombardier press release is entitled New PRIMOVE battery for rail presented at InnoTrans exhibition.

This is said.

The TALENT 3 EMU with PRIMOVE battery system will provide an environmentally friendly alternative to diesel trains operating on non-electrified lines. The results will significantly reduce noise pollution and emissions while making rail passenger transport cleaner and more attractive. Operators and passengers will also benefit from a battery technology that eliminates the need to change trains when bridging non-electrified track sections.

Other documents and web pafes emphasise how Primove is for all tranport applications. Thjs is the Primove web site.

In their data sheet, Bombardier said this.

For the first time TALENT EMU train is compatible with the BOMBARDIER PRIMOVE Li-ion battery system.

Reading about Primove, it would appear to be various standard modules.

Supposing you fit a train with the a standard Primove battery. This will give a defined range and performance to a p[articular train or tram with a specfic size battery.

As an electrical engineer and a control engineer in particular, I would suspect that the connections and the control system are the same for all batteries and that provided the battery can fit within the space allocated, all sizes will fit all trains.

So a suburban trundler would probably have less battery capacity, than a fast regional express, that stopped and started  quickly all the time.

If you want more range and performance, you just fit a bigger or more efficient battery.

I suspect too, that if an innovative company came up with another battery design, perhaps based on something like several miles of strong knicker elastic, so long as the plugs fit and it goes in the standard space, Bombardier would at least look at it.

So it looks like the fitting of batteries could be totally scale-able and future-proofed to accept new innovative battery technologies.

Aventras And Batteries

There has been no direct mention of batteries on Aventras

This is the best information so far!

This article in Global Rail News from 2011, which is entitled Bombardier’s AVENTRA – A new era in train performance, gives some details of the Aventra’s electrical systems. This is said.

AVENTRA can run on both 25kV AC and 750V DC power – the high-efficiency transformers being another area where a heavier component was chosen because, in the long term, it’s cheaper to run. Pairs of cars will run off a common power bus with a converter on one car powering both. The other car can be fitted with power storage devices such as super-capacitors or Lithium-Iron batteries if required.

Bombardier have confirmed the wiring for onboard power storage to me.

But you have to remember that the Talent 3 is for the more generous European loading gauge.

So could it be that Bombardier’s standard Primove system fits the Talent 3 and it’s too big for an Electrostar and an Aventra designed on standard lines?

But possibly, splitting the various heavy electrical components between two cars, as indicated in the Global Rail News article, gives more space for fitting a standard Primove battery and distributes the weight better.

Perhaps they can even fit a standard Primove battery into an Aventra, if it has the underfloor space to itself!

Obviously, using the same batteries in a Talent 3 and an Aventra must have cost and development advantages. Especially, if you can size the battery for the application.

Electrostars And Batteries

It has always puzzled me, why some Electrostars with an IPEMU-capability have not appeared. Could it be, that the amount of electrical equipment required is too much for a standard design of train running on a UK loading gauge?

Bombardier must have a target range for a train running on batteries. Perhaps, the Electrostar can’t get that range, but the Aventra with its twin power-car design can!

I wonder if the Electrostar with batteries and an IPEMU-capability will borrow from the Aventra design and have twin power-cars. That could be a much more major modification than that performed on a Class 379 train to create the BEMU denonstrator early last year.

But it could enable the use of a standard Primove battery and obtain the range needed for a viable Electrostar with an IPEMU-capability.

Crossrail And Energy

Crossrail is unlike any other railway, I’ve ever seen, with the exception of the RER under Paris.

  • Crossrail will be deep and all stations will have platform edge doors.
  • Crossrail will have twenty-four trains per hour.
  • A fully loaded Crossrail train going at the design speed of 145 kph has an energy of 105.9 kWh.

All of these and other factors will lead to lots of energy and heat being introduced into the stations, trains and tunnels.

One way of minimising problems is to design the the tunnels, trains, stations and electrical systems together.

As an example of how systems interact consider this. A train pulling away from the station needs a lot of energy to get to line-speed. In a traditional design, there could be a lot of energy wasted as heat in the overhead wires getting the electricity to the train. This heat would then need more air-conditioning to cool the platforms and the train.

So in this and many ways, saving energy, not only saves costs, but leads to further energy saving elsewhere.

Because of enegy problems, railways like Crossrail have to be designed very carefully with respect to energy usage.

Class 345 Trains

A few facts about Class 345 trains, for Crossrail, from their fact sheet.

  • They have been specifically designed for Crossrail.
  • Regenerative braking is standard.
  • High energy efficiency.
  • Acceleration is up to 1 m/s² which is more than an |Electrostar.
  • Maintenance will be by the manufacturer in purpose-built depots.

From this I conclude that it is in Bombardier’s interest to make the train efficient and easy to service.

I also founds this snippet on the Internet which gives the formation of the new Class 345 trains.

When operating as nine-car trains, the Class 345 trains will have two Driving Motor Standard Opens (DMSO), two Pantograph Motor Standard Opens (PMSO), four Motor Standard Opens (MSO) and one Trailer Standard Open (TSO). They will be formed as DMSO+PMSO+MSO+MSO+TSO+MSO+MSO+PMSO+DMSO.

As the article from Global Rail News  said earlier, the power system of an Aventra is based on two cars, with the heavy equipment split. So as each half-train seems to have be DMSO+PMSO+MSO+MSO in a Class 345 train, could the trains be using a three-car power system, with one car having the converter and batteries in the other two, all connected by a common bus.

It should also be noted that most Electrostar pantograph cars, don’t have motors, but the Class 345 trains do. Thus these trains must have prodigious acceleration with thirty-two diving axles in a nine-car formation.

There are also sound engineering and operational reasons for a battery to be fitted to the Class 345 trains.

  • Handling regenerative braking in the tunnels. As a train stops in a tunnel station, the regenerative brakes will generate a lot of energy. It would be much more efficient if that energy was kept in batteries on the train, as the tunnel electrical systems would be much simpler. There could also be less heat generated in the tunnels, as the overehead cables would be carrying less power to and from the trains.
  • Remote wake-up capability. Trains warm themselves up in the sidings to await the driver, as doiscussed in Do Bombardier Aventras Have Remote Wake-Up?
  • The depots could be unwired. I’ve read that the main Old Oak Common depot is energy efficient. Batteries on the trains would move the trains in the depots.

But the biggest advantage is that if power fails in the tunnel, the train can get to the next station using the batteries. In a worst case scenario, where the train has to be evacuated, the batteries could keep the train systems like air-conditioning, doors and communication working, to help in an orderly evacuation via the walkway at the side of the track.

How do you open the doors on a boiling train with fifteen hundred panicking passengers and no power? An appropriately-sized battery solves the problem.

Incidentally, I have calculated that a Class 345 train, loaded with 1,500 80 Kg people travelling at 145 kph has an energy of 105.9 kWh. As s Nissan Leaf electric car can come with a 50 kWh battery, I don’t believe that capturing all that braking energy on the train is in the realm of fantasy.

One big problem with regenerative braking on a big train with these large amounts of energy, must be that as the train stops 105.9 kWh must be fed back through the pantograph to the overhead line. And then on starting-up again 105.9 kWh of energy must be fed to the train through the pantograph, to get the train back up to speed.

As this is happening at a crowded station like Bond Street, twenty-four times an hour in both directions, that could mean massive amounts of energy flows generating heat in the station tunnels.

Remember that London’s tube train are smaller, have similar frequencies and have regenerative braking working through a third-rail system.

Surely, if the train is fitted with a battery or batteries capable of handling these amounts of energy, it must be more efficient to store and recover the energy from the batteries.

Batteries also get rid of a vicious circle.

  • Feeding the braking energy back to the overhead wire must generate heat.
  • Feeding the start-up energy to the train from the overhead wire must generate heat.
  • All this heat would need bigger air-conditioning, which requires more energy to be drawn by the train.

Batteries which eliminate a lot of the high heat-producing electricity currents in the tunnels at stations, are one way of breaking the circle and creating trains that use less energy.

After writing this, I think it is obvious now, why the trains will be tested in short formations between Liverpool Street and Shenfield.

The trains could be without any batteries during initial service testing, as all the reasons, I have given above for batteries don’t apply on this section of Crossrail.

  • Regenerative braking can either work using two-way currents on the upgraded overhead wiring or not be used during testing.
  • Remote wake-up is not needed, as the trains will be stored overnight at Ilford depot initially.
  • Ilford depot is still wired, although the jury may be out on that, given the depot is being rebuilt.
  • There will be no need to do rescues in tunnels.

Once the trains have proven they can cope with herds of Essex girls and boys, batteries could be fitted, to test their design and operation.

You have to admire Bombardier’s careful planning, if this is the way the company is going.

Could the following be the operating regime for Crossrail going from Shenfield to Reading?

  • The train runs normally between Shenfield and Stratford, using regenerative braking through the overhead wires or batteries.
  • The train arrives at Stratford with enough power in the batteries to come back out or get to a station, if there was a total power failure.
  • The train uses regenerative braking with the batteries between Whitechapel and Paddington.
  • In the tunnels, the power levels in the batteries, are kept high enough to allow train recovery.
  • Once in the open, regenerative braking could use overhead wires or batteries as appropriate.
  • The train even handles complete power failure and perhaps a problem with one pair of power cars, as the train is in effect two half-trains coupled together, with at least two of everything.

Has there ever been a train design like it?


It looks to me, that the Aventra and Talent 3 trains are just different-sized packages for the same sets of components like Flex-Eco bogies and Primove batteries.

One train is for the UK and the other for Europe and the rest of the world.

But have the two design teams been borrowing ideas and components from both sides of the Channel?

You bet they have!

Brexit? What Brexit?

The engineers of Crossrail, have not only dug one of the biggest holes in Europe for a long time, but with Bombardier’s engineers, they could also have designed a very efficient and different way of getting passengers through it.

I am very strongly of the opinion, that putting batteries on the trains to handle regenerative braking in tunnels, is almost essential, as it is simpler, possibly more affordable and cuts the amount of heat generated in the tunnels.



September 24, 2016 Posted by | Transport/Travel | , , , , , , | 3 Comments

Extending Crossrail To Gravesend

When I started to write Along The North Kent Line, I didn’t think that my conclusions would involve Crossrail.

I was wrong, so I’ve decided to write about extending Crossrail to Gravesend as a separate post.

Crossrail to Gravesend

Under Future in the Wikipedia entry for Gravesend station, this is said.

In December 2008, the local authority for Gravesend (Gravesham Council), was formally requested by Crossrail and the Department for Transport, to sanction the revised Crossrail Safeguarding. This safeguarding provides for a potential service extension, from the current south of Thames terminus at Abbey Wood, to continue via the North Kent Line to Gravesend station. The Crossrail route extension from Abbey Wood to Gravesend and Hoo Junction, remains on statute. With current services from Gravesend to London Bridge, Waterloo East and London Charing Cross being supplemented by highspeed trains from the end of 2009 to St Pancras, the potential in having Crossrail services from central London, London Heathrow, Maidenhead and/or Reading, terminating at Gravesend, would not only raise the station to hub status but greatly contribute towards the town’s regeneration.

So it would appear that the route is safeguarded to Gravesend and Hoo Junction and it remains on statute.

Current Services At Gravesend

At present, Gravesend station has the following typical Off Peak service.

  • 2 trains per hour (tph) Highspeed services in each direction between London St. Pancras, Ebbsfleet International and Faversham and the East.
  • 2 tph Southeastern services between London Charing Cross and Gillingham.
  • 4 tph Southeastern services between London Charing Cross and Gravesend.

From 2019, Thameslink are saying that they will be running two tph between Rainham and Luton via Dartford and Greenwich.

This will mean that eight tph in each direction will go between Gravesend and Dartford, with another two tph going between Gravesend and Ebbsfleet International.

Because of the  new Thameslink service, the train frequency between Gravesend and Gillingham will increase from the current four tph to six tph.

Gravesend As A Crossrail Terminal

I think that although Gravesend will be the nominated terninal for Crossrail, the trains will actually reverse direction at Hoo Junction, so there will be no need to use any platform space at Gravesend to prepare the train for its return journey.

Gravesend and Hoo Junction, will work very much like London Bridge and Cannon Street, where trains call at the first station and are reversed at the latter. Hoo Junction would just be a depot and a set of sidings.

I also think that the facilities at Hoo Junction could be built with minimal electrification, as the Crossrail Class 345 trains may have enough onboard energy storage to handle movement in depots and remote wake-up, which I discussed in Do Bombardier Aventras Have Remote Wake-Up?.

Class 345 trains have an auto-reverse ability which I talked about in Crossrail Trains Will Have Auto-Reverse. Will this be used to turn the trains at Hoo?

Crossrail’s Service To Abbey Wood

At present, Wikipedia is saying this will be the Morning Peak Crossrail service from Abbey Wood station.

  • 4 tph to Heathrow Terminal 4
  • 6 tph to Paddington
  • 2 tph to West Drayton

With this Off Peak service.

  • 4 tph to Heathrow Terminal 4
  • 4 tph to Paddington

This gives totals of 12 tph in the Peak and 8 tph in the Off Peak.

Crossrail Frequency To Gravesend

What the current North Kent Line can handle would probably determine how many Crossrail trains travel to Gravesend and Hoo Junction.

But Crossrail won’t be short of seats to really provide a superb service to and from the Gravesend.

I think that 4 tph could probably be fitted into the timetables between Abbey Wood and Gravesend. This would give.

  • 10 tph between Abbey Wood and Dartford
  • 12 tph between Dartford and Gravesend.

Six of the trains between Abbey Wood and Gravesend would be the two hundred metro long trains of Crossrail and Thameslink.

As the signalling is all new, I suspect that the line could cope.

The service level does generate some questions.

  • Would Thameslink need to run a twelve-car train on the Rainham to Luton service?
  • Dartford is a big winner, so will the other services from Dartford be re-routed?
  • How many services would stop at Greenhithe for Bluewater?
  • How would Crossrail’s Western destinations be allocated between Abbey Wood and Gravesend?

Connecting To Ebbsfleet International

I think it is essential that Crossrail connects to Continental train services and as the cross-London line goes nowhere near to St. Pancras, the connection must be made at either the draughty Stratford International or the truly dreadful Ebbsfleet International.

Talk about choosing the lesser of two evils, one of which; Stratford, should but doesn’t have Continental services!

So the connection between the Crossrail, Thameslink and the North Kent Line and Ebbsfleet International must be improved.

Possible connections could be.

  • A shuttle bus from Northfleet station.
  • A decent people mover or travellator from Northfleet station
  • A shuttle bus from Gravesend.
  • More train services from Gravesend.

There is of course the option of creating a proper rail link. But that would be expensive.

I think that as the number of trains stopping at Northfleet station will be somewhere around ten tph in each direction, a frequent shuttle bus might be a good option to start with.

The problem with the trains, is that there is only two tph between Gravesend and Ebbsfleet International.

Building The Crossrail Extension

I have a feeling that once Crossrail is running successfully, the traffic will define, if, when and how any extension to Gravesend is built.

But the creation of the extension to Gravesend and Hoo Junction will not be a massive undertaking.

  • The depot and other facilities at Hoo Junction will have to be built.
  • Could the depot at Hoo Junction be without electrification? If the Class 345 trains have sufficient onboard energy storage, which I believe could be the case and I wrote about in Bombardier’s Plug-and-Play Train, then this is a serious possibility, which would save money and time in building the depot.
  • All platforms are probably long enough for the Class 345 trains.
  • The Crossrail train specification says that trains must have the potential to be converted for third rail operation. The similar Class 710 trains will have this capability.
  • Judging by my observations in Between Abbey Wood And Belvedere Stations, I feel that Abbey Wood station is probably capable of handling the same number of trains as it is planned on opening, even if some go further down the line.
  • The signalling would have to be adjusted for the new service pattern. But thre signalling has been upgraded!

But there would be no tunnelling and no major electrification on the North Kent Line.

Perhaps, the only major expenses would be.

  • Building the depot/reversing sidings and facilities at Hoo Junction.
  • Any extra trains needed.
  • The cost of any rail link into Ebbsfleet International station.

So I doubt, we’ll be talking large numbers of billions.

Related Posts

A Design Crime – Ebbsfleet International Station

A Trip To Sheppey

A Twelve-Car Ready Railway

Along The North Kent Line

Between Abbey Wood And Belvedere Stations

Connecting North Kent And The Medway Towns To Ebbsfleet International Station

Rainham (Kent) Station

Thameslink To Rainham

Through The Medway Towns

What Do You Do With A Problem Like Sheppey?

September 22, 2016 Posted by | Transport/Travel | , , , , | 8 Comments

Could Electrification Be Removed From The Chingford Branch Line?

This article in Rail Engineer also quotes Jon Shaw of Bombardier on onboard energy storage in the new Aventra trains, like the Class 710 trains that will work the Chingford Branch Line.

As part of these discussions, another need was identified. Aventra will be an electric train, but how would it serve stations set off the electrified network? Would a diesel version be needed as well?

So plans were made for an Aventra that could run away from the wires, using batteries or other forms of energy storage. “We call it an independently powered EMU, but it’s effectively an EMU that you could put the pantograph down and it will run on the energy storage to a point say 50 miles away. There it can recharge by putting the pantograph back up briefly in a terminus before it comes back.

I believe that once the concept of onboard energy storage is accepted, that Network Rail and operators, will question whether there is a need for so much electrification.

In a few years time, all trains, except perhaps a few engineering ones, on the Chingford Branch Line North of St. James station will be new Class 710 trains with the following characteristics.

  • Enough onboard energy storage to handle regenerative braking and handle the twenty mile out-and-back trip on the branch.
  • By using onboard energy storage, the trains have a remote wake-up facility, as discussed in Do Bombardier Aventras Have Remote Wake-Up?.
  • The ability to raise and lower a pantograph quickly.

So would it be possible to remove electrification, North of Clapton Junction.

This map from shows the area of Coppermill junction, with the Chingford Branch Line shown conveniently in orange.

Coppermill Junction

Coppermill Junction

I will now list the advantages of removing the electrification between Clapton Junction and Chingford.

Maintaining The Overhead Wires

Overhead wires get damaged, vandalised and stolen at a surprisingly high frequency.

Network Rail would love to see the wires come down.

The only objectors would be the thieves, who nick the wires to sell.

The Sidings At Chingford Could Be Without Electrification

As all the trains stored there would have their own onboard energy storage, they would move in and out under their own power.

The Chingford sidings could thus be without electrification.

This would.

  • Reduce maintenance costs for the sidings.
  • Enable track layouts to be changed without changing the electrification.
  • Increase safety levels for everybody working in the sidings.

The only electrification needed at Chingford might be a short stretch of overhead wire to top up trains low on electricity.

All Height Restrictions Could Be Removed At The Highams Park Level Crossing

After the recent accident on the M20, reported in this story on the BBC,, which is entitled M20 motorway shut after lorry crash causes bridge collapse, I don’t think it is wise to underestimate the stupidity of some drivers.

So if there were no overhead wires at the Highams Park level crossing, it might avoid a serious incident.

Easing Station Rebuilding and Building

Wood Street station needs to be rebuilt to make the station step-free and it would be much easier and less disruptive to train services, if there were no overhead wires to get in the way.

If any new stations are added to the line, then the cost of building must be more affordable, if there are no overhead wires to get in the way.

Less Visual and Noise Intrusion

Obviously, removal of overhead wires will reduce the visual intrusion.

But, it will also reduce the noise, as overhead wires are a source of noise from electric trains.

Note too, that as the new trains will use regenerative braking at most times, there will be much less noise from wheel-brakes.

A Safer Railway

There is no doubt, that a railway without electrification is a safer railway, as there is no electricity, except for points and signals.


It would be advantageous for several reasons if electrification could be removed from the Chingford Branch Line.

Related Posts

Improving The Chingford Branch Line

Could Reversing Sidings Be Used On The Chingford Branch Line?

Could The Hall Farm Curve Be Built Without Electrification?

New Stations On The Chingford Branch Line

Rumours Of Curves In Walthamstow

Will Walthamstow Central Station On The Victoria Line Be Expanded?

Wikipedia – Chingford Branch Line

September 8, 2016 Posted by | Transport/Travel | , , , | 6 Comments

Improving The Chingford Branch Line

The Chingford Branch Line has a four trains per hour (tph) service between Liverpool Street and Chingford via Hackney Downs and Walthamstow Central stations.

Those that I know who live in the area, have a few simple wishes.

  • New trains with wi-fi and other passenger-friendly features.
  • More trains to improve services and take the pressure off the Victoria Line.
  • A service from Chingford and Walthamstow to Stratford and Crossrail.
  • Perhaps some new stations.
  • Step-free access at St. James Street and Wood Street stations.

The following sections tackle these wishes in more detail.

New Class 710 Trains

The biggest change to the line will come with the new Class 710 trains in a couple of years time.

Thirty new four-car Class 710 trains will replace the same number of Class 315 and Class 317 trains, that currently work the  Cheshunt and Chingford services.

  • As the number of trains and their length is the same, the service frequency and capacity will be no worse than at present.
  • The trains will be modern and have air-conditioning and all the features that passengers now expect.
  • The trains will be fitted with various driver aids to ensure accurate timekeepers.
  • Nothing has been said about wi-fi, but most other new Aventras will have free wi-fi fitted, so I suspect it will be fitted or there will be a big argument.
  • I am of the belief that all Class 710 trains will be fitted with enough onboard energy storage to handle regenerative braking and short movements not connected to the overhead wires.
  • Onboard energy storage would also mean the trains could be fitted with remote wake-up, so that trains stabled overnight at Chingford, can be driver and passenger ready before the driver arrives to start the service in the morning.

It should be noted that London Overground has taken an option for another twenty-four trains. So could some of these trains be added to the fleet on the Chingford Branch to increase capacity and service on the Branch?

The Highams Park Level Crossing

In an ideal world, more services would be provided on the Chingford Branch to Liverpool Street for the following reasons.

  • The Victoria Line from Walthamstow Central now has the trains to handle passengers to Central London, but the station doesn’t have the capacity to handle them, due to its cheapskate 1960s design.
  • The Chingford Branch has direct access to Crossrail at Liverpool Street whereas the Victoria Line doesn’t connect to London’s new train line.
  • The Chingford Branch has direct access to the North London Line at Hackney Downs and the new Class 710 trains, will mean that North London Line services will be increased.
  • Crossrail could release extra platform space at Liverpool Street for  more London Overground services.

But there is one major problem to increased services on the current Chingford Branch. They must all go through the level crossing at Highams Park Station.

  • There is only long detours, if the crossing is closed.
  • Extra trains would cause significant traffic congestion.
  • Extra trains would mean the crossing would be closed for a large proportion of every hour.

As it is unlikely that the money could be found for a bridge or tunnel at Highams Park, the only thing that can be done, is make sure that all train services be at maximum length, which is probably eight cars.

Obviously, longer trains would help, but in the long term, I’m certain that London Overground would want to run more frequent services between Liverpool Street and Chingford.

I think it is true to say that the train frequency of the Chingford Branch through Highams Park is probably limited by a maximum of eight closures per hour of the Highams Park level crossing, unless the level crossing could be closed or by-passed.

But is maximum use being made of the level crossing closures now?

At present in the Off Peak.

  • Trains arrive at Highams Park from Chingford at 14, 29, 44 and 59 minutes past the hour.
  • Trains leave Highams Park for Chingford at 08, 23, 38 and 53 minutes past the hour.

I don’t think that this means that a Northbound and a Southbound train can share a single closure of the level crossing. This page on the National Rail web site, shows live departures at Highams Park.

If they could, then that would cut the number of times the crossing closed in the Off Peak by half.

Things that will help, is that the Class 710 trains will have extensive driver aids and probably onboard signalling, so the precise timekeeping that would be required, so two trains shared a level crossing closure, could be a lot easier.

Eight trains per hour in the Off Peak in both direction through Highams Park station is a distinct possibility.

This 8 tph frequency could be continued through the Peak, as it’s probably better than the current timetable.

Eight Trains Per Hour From St. James Street To Chingford

So it looks like that modern Class 710 trains running to a precise timetable could mitigate the problems of the Highams Park Level Crossing and allow eight trains per hour between St. James Street and Chingford.

|As there is no other trains using the branch, except moving empty and some engineering trains to and from the sidings at Chingford, there is probably little to interfere with an 8 tph schedule.

South From St. James Street

South from St. James Street station, the trains go through the Coppermill Junction area and cross the West Anglia Main Line.

The Chingford Branch then joins the line from Tottenham Hale to Hackney Downs, as this map from shows.


Coppermill Junction

Coppermill Junction

The map shows Coppermill Junction, where the Chingford Branch Line crosses the West Anglia Main Line, that runs North from Liverpool Street to Tottenham Hale, Bishops Stortford, Stansted Airport and Cambridge.

I suspect that there would be a problem fitting another four tph through Hackney Downs station and on to Liverpool Street.

In Rumours Of Curves In Walthamstow, I talked about how two curves would be rebuilt, based on information from an informant with detailed knowledge.

  • The Hall Farm Curve would be rebuilt as a bi-directional single-track connection between St. James and Lea Bridge stations.
  • The Coppermill Curve would be rebuilt to give a connection between St. James and Tottenham Hale stations.

The Hall Farm Curve is the significant one for passenger services on the Chingford Branch Line, as it would mean that the current service of 4 tph between Chingford and Liverpool Street would be augmented by a second 4 tph between Chingford and Stratford.

  • Waltham Forest would get an 8 tph metro service between St. James and Chingford stations.
  • There are extensive bus connections at Chingford, Walthamstow Central and Stratford.
  • The line has good connections to the Victoria Line, the Jubilee Line, the Central Line and Crossrail.

The only infrastructure needed would be the single-track Hall Farm Curve. If the Class 710 trains were to be fitted with onboard energy storage, this curve would not even need to be electrified.


By using the  features of the new Class 710 trains, Chingford can be given four trains per hour to Liverpool Street and 4 trains per hour to Stratford, if a new single-track Hall Farm Curve without electrification is built between St. James and Lea Bridge stations.

Related Posts

Could Electrification Be Removed From The Chingford Branch Line?

Could Reversing Sidings Be Used On The Chingford Branch Line?

Could The Hall Farm Curve Be Built Without Electrification?

Crossrail 2 And The Chingford Branch Line

New Stations On The Chingford Branch Line

Rumours Of Curves In Walthamstow

Will Walthamstow Central Station On The Victoria Line Be Expanded?

Wikipedia – Chingford Branch Line



September 7, 2016 Posted by | Transport/Travel | , , , , | 14 Comments

Comparing An Aventra IPEMU With An Electrostar IPEMU

The Concept Of An IPEMU

This article in Rail Engineer, which is entitled An Exciting New Aventra, quotes Jon Shaw of Bombardier on onboard energy storage.

As part of these discussions, another need was identified. Aventra will be an electric train, but how would it serve stations set off the electrified network? Would a diesel version be needed as well?

So plans were made for an Aventra that could run away from the wires, using batteries or other forms of energy storage. “We call it an independently powered EMU, but it’s effectively an EMU that you could put the pantograph down and it will run on the energy storage to a point say 50 miles away. There it can recharge by putting the pantograph back up briefly in a terminus before it comes back.

I believe that once the concept of onboard energy storage is accepted, that Bombarduier’s engineers have found other ways to use it to the benefit of passengers, operators and Network Rail.

  • Regenerative braking energy can be stored on the train and used for a restart or other purposes, rather than just burning it off or returning it to the grid, through complicated transformers.
  • Onboard energy can be used to move a train to the next station, if the overhead or third rail power should fail.
  • Depots and stabling sidings don’t need to be fully electrified.
  • Onboard energy storage enables train features like remote wake up, which I discussed in Do Bombardier Aventras Have Remote Wake-Up?.
  • Trains can safely pass over short sections without electrification. Third rail trains can do this with contact shoes at both ends of the train.

Trains with onboard energy probably need to have intelligent current collection, so that pantographs and contact shoes can be intelligently deployed and retracted.

Take the simple example of a passing loop on a single track electrified branch line, which is needed for two trains per hour. The passing loop could be built without electrification and without altering the existing electrification, with just a set of points and appropriate signalling at each end.

  • Trains using the existing line and electrification would travel as now.
  • Electric trains using the loop would lower the pantograph a safe distance before the loop, go along the passing loop using onboard energy  and then once on the main line, raise the pantograph.

This technique could probably be used to simplify building of new stations or adding new platforms to existing ones.

Network Rail are going to love trains with onboard energy storage.

Electrostars and Aventras

Bombadier have shown that onboard energy storage is possible in an Electrostar and there is various articles on the web saying it can be fitted to the new Aventra.

As both Aventras and Electrostars seem to come in four- and five-car versions, I’ll do the calculations for both lengths of trains.

I’ll use these assumptions.

  • Electrostar cars weigh 40 tonnes and Aventra cars 32.5 tonnes.
  • Each car has 50 passengers weighing an average of 80 kilos.

The various types of IPEMU are shown in the next four sections.

Four-car Electrostar

This would have the following characteristics.

  • A mass of 160+16 = 176 tonnes.
  • A formation of DMOS+MOS+PTSO+DMOS
  • Braking from 100 kph would release 18.9 KWH.
  • Braking from 200 kph would release 75.5 KWH.
  • Onboard energy storage could be placed in probably the MSO or PTSO cars.


This could be created from a train like a Class 377, Class 378, Class 379 or Class 387 train.

We know that in the demonstration using a Class 379 at Manningtree, that that train could do 18.2 km. on the Mayflower Line, just by the use of battery power.

Five-car Electrostar

This would have the following characteristics.

  • A mass of 200+20 = 220 tonnes.
  • A formation of DMOS+MOS+PTSO+MOS+DMOS
  • Braking from 100 kph would release 23.6 KWH.
  • Braking from 200 kph would release 94.3 KWH.
  • Onboard energy storage could be placed in probably the MSO or PTSO cars.

Four-car Aventra

This would have the following characteristics.

  • A mass of 130+16 = 146 tonnes.
  • A formation of DMOS+MOS+PMSO+DMOS
  • Braking from 100 kph would release 15.6 KWH.
  • Braking from 200 kph would release 62.6 KWH.
  • Bombardier have stated that the MOS car is ready for onboard energy storage.


This could be created from a train like a Class 710 train.

Five-car Aventra

This would have the following characteristics.

  • A mass of 162.5+20 = 182.5 tonnes.
  • A formation of DMOS+MOS+PMSO+MSO+DMOS.
  • Braking from 100 kph would release 19.6 KWH.
  • Braking from 200 kph would release 78.2 KWH.

The five-car Aventra could have two sets of batteries or onboard energy storage.

Note this about all Aventras.


Bombardier have stated that the MSO car is ready for onboard energy storage, if the customer desires.

The MSO and PMSO cars can be considered a fixed pair of cars handling the electrical power for the train.

Can a PMSO and two MSOs be considered a trio on the five-car Aventra?

Aventras have a lot of motored cars, with lots of traction motor/generators.

The trains can have a remote wake-up feature, that would probably need some form of onboard energy. After all, your smart-phone doesn’t work if the battery is not fitted.

Can I draw any conclusions?

  • The Aventra with its pair of electrifical cars has been designed to have onbosrd energy storage.
  • The energy that needs to be handled is less with the lighter weight Aventra.
  • Stopping from 200 kph releases a lot more energy. Four times more than from 100 kph in fact.
  • The energy storage needed for 100 kph stop and restart operation, are within the battery size range of the battery in an electric car like a Nissan Leaf.
  • There could be advantages concerning reliability and battery size with the five-car Aventra with its possible two sets of energy storage.

Obviously, the weight of the battery would need to be factored into the calculations, but if say it was a tonne, it would only increase energy figures by less than one percent.

The Definitive IPEMU

I said that two two sets of energy storage in the five-car Aventra could give advantages.

  • Each set could be smaller.
  • Two sets will be more reliable than one.
  • The weight of the storage is shared between two MSO cars.
  • The two MSO cars in the five-car Aventra IPEMU would probably be identical.

In the extract from the Rail Engineer article that started this post Jon Shaw of Bombardier is quoted as saying this.

it will run on the energy storage to a point say 50 miles away.

Two sets of onboard storage would obviously help this, with each set needed to keep the train going for 25 miles. This is not the onerous task it could appear. Especially in an Aventra.

  • The train is designed to minimise aerodynamic losses.
  • The train is designed to minimise the very small rolling losses of steel wheel on steel rail.
  • All passenger systems like wi-fi, lighting and air-conditioning are designed to use minimum electricity.
  • Driving aids on the train will help the driver to drive in an energy efficient way.
  • When the brakes are applied, the energy is recovered and stored in the onboard energy storage.
  • The train will stop at a station using much less energy than a conventional train.

But the most important thing, is that the train has been designed from the wheels up as an efficient package.


I believe the following.

  • Five cars will be one of the most common lengths for Aventras. Abellio have already ordered eighty-nine.
  • The range on energy storage of a five-car Aventra with two sets of energy storage will be at least fifty miles.
  • Aventras with an IPEMU-capability will be used to reduce electrification work.
  • Aventras with an IPEMU-capability will be used to develop new electrified routes.
  • As the IPEMU technology develops, Bombardier will develop a solution, so that later Electostars will be able to store their own braking energy and travel a limited distance away from electrification.
  • All train manufacturers will look seriously at energy storage on trains.

If I was asked what would be the ultimate range of a train using this technology, I would say, that trains with an IPEMU-capability will within a few years be running the whole route between Waterloo and Exeter.



September 6, 2016 Posted by | Transport/Travel | , , , | Leave a comment