The Anonymous Widower

Alstom And Eversholt Rail Sign An Agreement For The UK’s First Ever Brand-New Hydrogen Train Fleet

The title of this post, is the same as that of this press release from Alstom.

This is the first two paragraphs.

Alstom, Britain’s leading train manufacturer and maintenance provider, and Eversholt Rail, leading British train owner and financier, have today announced a Memorandum of Understanding aimed at delivering the UK’s first ever brand-new hydrogen train fleet.

The two companies have agreed to work together, sharing technical and commercial information necessary for Alstom to design, build, commission and support a fleet of ten three-car hydrogen multiple units (HMUs). These will be built by Alstom in Britain. The new HMU fleet will be based on the latest evolution of the Alstom Aventra platform and the intention is that final contracts for the fleet will be signed in early 2022.

This is an Alstom visualisation of the train.

The first thing I notice is that the train doesn’t have the same aerodynamic nose as this current Class 710 train, which is one of the London Overground’s Aventras.

Note how the lights, coupler position and the front-end structure are all different.

These are my further thoughts on the design.

The Aventra’s Traction System

In 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-ion batteries if required. The intention is that every car will be powered although trailer cars will be available.

Unlike today’s commuter trains, AVENTRA will also shut down fully at night. It will be ‘woken up’ by remote control before the driver arrives for the first shift

This was published over ten years ago, so I suspect Bombardier (or now Alstom) have refined the concept.

Bombardier have not announced that any of their trains have energy storage, but I have my suspicions, that both the Class 345 and Class 710 Aventra trains use super-capacitors or lithium-ion batteries, as part of their traction system design.

• I was told by a Bombardier driver-trainer that the Class 345 trains have an emergency power supply. When I said “Batteries?”, He gave a knowing smile.
• From the feel of riding on Class 710 trains, as a Control Engineer, I suspect there is a battery or supercapacitor in the drive system to give a smoother ride.

I also feel that the Aventra has been designed, so that it can accept power from a large variety of sources, which charge the battery, that ultimately drives the train.

The Formation Of A Three-Car Aventra

The only three-car Aventra is the Class 730/0 train.

I have not seen one of one of these trains in the metal and the formation can’t be found on the Internet. But Wikipedia does show the pantograph on the middle car.

In The Formation Of A Class 710 Train, I said this.

Here is the formation of the train.

DMS+PMS(W)+MS1+DMS

The plates on the individual cars are as follows.

DMS – Driving Motored Standard

• • Weight – 43.5 tonnes
  • Length – 21.45 metres
  • Width 2.78 metres
  • Seats – 43

The two DMS cars would appear to be identical.

PMS  -Pantograph Motored Standard

• • Weight – 38.5 tonnes
  • Length – 19.99 metres
  • Width 2.78 metres
  • Seats – 51

The  signifies a wheelchair space.

MS1 – Motored Standard

• • Weight – 32.3 tonnes
  • Length – 19.99 metres
  • Width 2.78 metres
  • Seats – 52

It is similar in size to the PMS car, but has an extra seat.

So could the formation of a three-car Aventra be?

DMS+PMS(W)+DMS

I have just removed the MS1 car.

This would mean that a three-car Aventra has the following dimensions and capacity.

• Weight – 125.5 tonnes
• Length – 62.89 metres
• Seats – 137

There will probably be a difference between these figures and those of a three-car Class 730 train, as those trains have end-gangways.

Could All The Hydrogen Gubbins Fit Underneath The Train?

These pictures show the space underneath a Class 710 train.

If you also look at Alstom’s visualisation of their Hydrogen Aventra on this post, there would appear to be lots of space under the train.

It should also be noted  that Birmingham University’s engineers have managed to put all of the hydrogen gubbins underneath the floor of Porterbrook’s Class 799 train.

Looking at my pictures, you can see the following.

• The two DMS (Driving Motored Standard) cars have large boxes underneath
• The MS1(Motored Standard) car is fairly clear underneath. But this will probably not be there in a three-car train.
• The PMS (Pantograph Motored Standard) car has some space underneath.

If more space needs to be created, I suspect that the cars can be lengthened, between the bogies. The Class 710 trains have twenty metre intermediate cars, whereas some versions have twenty-four metre cars.

I believe that Aventras have been designed, so that various power sources could be installed under the floor.

When the Aventra was designed, over ten years ago, these could have included.

• A diesel generator and all the fuel tanks and cooling systems.
• A battery or other energy storage system.

Since then two other suitable power sources have been developed.

• Rolls-Royce, Honeywell and others have developed small and powerful gas-turbine generators.
• Ballard Power Systems and others have developed hydrogen fuel cell generators.

If you look at the proportions of the Alstom hydrogen train and the pictures of Class 710 trains, I feel that the Alstom train could have the longer twenty-four metre cars.

It may be a tight fit compared to creating the Alstom Coradia iLint hydrogen train, but I would feel it is possible to install a fuel cell or cells, the required cooling and the hydrogen tanks, having seen cutaway drawings of hydrogen-powered double-deck buses on the Wrightbus web site.

Interestingly, the Alstom press release doesn’t mention fuel cells, so could the train be powered by a small gas turbine?

I think it is unlikely, but it is technically feasible.

Does The Alstom Hydrogen Aventra Have Longer Cars?

I have been looking at pictures of Aventras on Wikipedia and in my own archive.

It appears that only Aventras with twenty-four metre carriages have five windows between the pair of double-doors in the intermediate carriages.

This picture shows the PMS car from a Class 710 train.

The PMS car is to the right and has four windows between the doors.

This is the side view of one of Greater Anglia’s Class 720 trains.

It has twenty-four metre intermediate cars and five windows.

It looks to me that the Alstom Hydrogen Aventra will have twenty-four metre cars.

This will give an extra four x 2.78 metres space under the train compared to a Class 710 train.

It would also appear that the Aventras with twenty-four metre cars also have an extra window in the driving cars, between the doors.

Does the four metre stretch make it possible to position tubular hydrogen tanks across the train to store a practical amount of hydrogen?

Is The Alstom Hydrogen Train Based On A Three-Car Class 730/0 Train?

I have just found this video of a three-car Class 730/0 under test.

And guess what! It has five windows between the doors.

But then it is a train with twenty-four metre cars.

It looks to me, that Alstom have looked at the current Aventra range and decided that the three-car Class 730/0 could be the one to convert into a useful train powered by hydrogen.

So if it is a Class 730/0 train with hydrogen gubbins under the floor, what other characteristics would carry over.

• I suspect Aventras are agnostic about power and so long as they get the right quantity of volts, amps and watts, the train will roll along happily.
• But it means that the train can probably use 25 KVAC overhead electrification, 750 VDC third-rail electrification, hydrogen or battery power.
• I wouldn’t be surprised if if could use 15 KVAC and 3KVDC overhead electrification for operation in other countries, with perhaps a change of power electronics or transformer.
• The interior layout of the trains can probably be the same as that of the Class 730/0 trains.
• The Class 730/0 trains have an operating speed of 90 mph and this could be good enough for hydrogen.

This could be a very capable train, that could find a lot of applications.

Could The Proposed Alstom Hydrogen Aventra Be Considered To Be A Class 730/0 Train With A Hydrogen Extender?

It appears that the only difference between the two trains is that the proposed Alstom Hydrogen Aventra has a hydrogen propulsion system, that can be used when the electrification runs out.

The hydrogen fuel cell will convert hydrogen into electricity, which will either be used immediately or stored in a battery on the train.

The Class 730/0 trains have already been ordered to run services on Birmingham’s electrified Cross-City Line.

There are plans to expand the line in the future and I do wonder if the proposed Alstom Hydrogen Aventras could be the ideal trains for extending the network.

How Does The Alstom Hydrogen Aventra Compare With The Class 600 Breeze Train?

The Class 600 train, which is based on the British Rail-era Class 321 train seems to have gone cold.

If it was a boxing match, it would have been stopped after the fourth round, if not before.

This Alstom visualisation shows the Class 600 train, which is also known as the Breeze.

I have a feeling that Alstom have done their marketing and everybody has said that the Class 600 train wouldn’t stand up to a modern train.

• When you consider that each end of the train is a hydrogen tank, I wonder if possible passenger and driver reaction has not been overwhelmingly positive.
• The project was announced in January 2021 and in the intervening time, hydrogen technology has improved at a fast pace.
• There could even be a battery-electric version of the proposed Alstom Hydrogen Aventra.
• The modern train could possibly be lengthened to a four or five car train.

It does strike me, that if Alstom are going to succeed with hydrogen trains, that to carry on with the Class 600 train without an order into the future is not a good idea.

How Does The Alstom Hydrogen Aventra Compare With The Alstom Coradia iLint?

The Alstom Coradia iLint is the world’s first hydrogen train.

It is successfully in service in Germany.

These are some characteristics of the Coradia iLint from the Internet.

• Seats – 180
• Length – 54.27 metres
• Width – 2.75 metres
• Height – 4.31 metres
• Operating Speed – 87 mph
• Range – 370-500 miles
• Electrification Use – No

The same figures for the Alstom Hydrogen Aventra are as follows.

• Seats – 164
• Length – 72 metres
• Width – 2.78 metres
• Height – 3.76 metres
• Operating Speed – 90 mph
• Range – Unknown
• Electrification Use – Unknown, but I would expect it is possible.

Note.

1. I have taken figures for the Alstom Hydrogen Aventra from the Class 730/0 train and other Aventras.
2. The number of seats is my best estimate from using the seat density of a Class 710 train in a 24 metre long car.
3. The width and height seem to be standard for most Aventras.
4. Alstom have said nothing about the range on hydrogen.
5. I am surprised that the Aventra is the wider train.

But what surprises me most, is how similar the two specifications are. Had the designer of the original Lint hoped to sell some in the UK?

What Is The Range Of The Alstom Hydrogen Aventra?

When they launched the Breeze, Alstom were talking about a range of a thousand kilometres or just over 620 miles.

I have talked to someone, who manages a large bus fleet and they feel with a hydrogen bus, you need a long range, as you might have to position the bus before it does a full day’s work.

Would similar positioning mean a hydrogen train needs a long range?

I suspect it would in some applications, but if the train could use electrification, as I suspect the Alstom Hydrogen Aventra can, this must help with positioning and reduce the range needed and the amount of hydrogen used.

Would Alstom aim to make the range similar to the Coradia iLint? It’s probably a fair assumption.

Could the Alstom Hydrogen Aventra Be Extended To Four Or Five Cars?

I don’t see why not, as Aventras are designed to be lengthened or shortened, by just adding or removing cars, just like their predecessors the Electrostars were.

I can certainly see routes, where a longer Alstom Hydrogen Aventra could be needed and if Alstom have also decided that such a train could be needed, they will surely have investigated how to lengthen the train.

Applications In The UK

These are links to a few thoughts on applications of the trains in the UK.

• Alstom Hydrogen Aventras And Extension Of The Birmingham Cross-City Line
• Alstom Hydrogen Aventras And The Reopened Northumberland Line
• Alstom Hydrogen Aventras And Great Western Branch Lines Between Paddington And Oxford
• Alstom Hydrogen Aventras And The Uckfield Branch

There are probably a lot more and I will add to this list.

Applications Elsewhere

If the Coradia iLint has problems, they are these.

• It can’t use overhead electrification, where it exists
• It has a noisy mechanical transmission, as it is a converted diesel multiple unit design.

The Alstom Hydrogen Aventra can probably be modified to use electrification of any flavour and I can’t see why the train would be more noisy that say a Class 710 train.

I suspect Alstom will be putting the train forward for partially-electrified networks in countries other than the UK.

Conclusion

This modern hydrogen train from Alstom is what is needed.

It might also gain an initial order for Birmingham’s Cross-City Line, as it is a hydrogen version of the line’s Class 730/0 trains.

But having a hydrogen and an electric version, that are identical except for the hydrogen extender, could mean that the trains would be ideal for a partially-electrified network.

There could even be a compatible battery-electric version.

All trains would be identical to the passenger and probably the driver too. This would mean that mixed fleets could be run by an operator, with hydrogen or battery versions used on lines without electrification as appropriate.

November 11, 2021 Posted by AnonW | Hydrogen, Transport/Travel | Alstom, Alstom Hydrogen Aventra, Aventra, Ballard Power Systems, Class 321 Hydrogen/Alstom Breeze, Class 345 Train, Class 600 Train, Class 710 Train, Class 720 Train, Class 730 Train, Coradia iLint, Cross-City Line, Honeywell, Hydrogen-Powered Trains, Rolls-Royce | 16 Comments