The Anonymous Widower

A Detailed Look At A Three-Car Aventra

In Bombardier and CAF To Make 413 Carriages For New West Midlands Franchise, I wondered if the three-car Aventras ordered by West Midlands Trains had a battery capability.

The Train Weight

I need a good estimate of the weight of a typical Aventra carriage.

Wikipedia gives the following values.

  • Bombardier Aventra – A nine-car Class 345  train weighs less than 350 tonnes, which gives a figure of 39 tonnes per car.
  • Siemens Desiro City – A twelve-car Class 700 train weighs 410 tonnes, which gives a figure of 34 tonnes per car.
  • Bombardier Electrostar – A five-car Class 378 train weighs 159.5 tonnes, which gives a figure of 32 tonnes per car.

Bombardier seem to play their weight figures close to their chest, so I’ll just use a figure of 35 tonnes per car. But it does appear that Aventras, could be heavier than Electrostars.

The Battery Weight

I tend to think in terms of New Routemaster hybrid bus batteries, which have a capacity of 75 kWh.  Surely hybrid bus batteries are fairly common and if you were needing a battery for a new application, it might be where you will start.

The best estimate I can make is that a 75 kWh battery weighs about 600 Kg. I will use this until I find a better figure.

Could the weight of the battery explain the increase in weight between an Electrostar and an Aventra?

Aventras Have A Lot Of Traction Motors

From what I’ve seen on the Internet, it appears that Aventras have a lot of powered bogies.

A Three-Car Aventra

I think that a three-car Aventra would have a formation something like.

  • DMSLW – Driver Motor Standard – Wheelchair and Universal Access Toilet
  • PMS – Pantograph Motor Standard
  • DMS – Driver Motor Standard

Note.

  1. I estimate it would have about 230 Standard Class seats in a traditional layout. or perhaps 150 in a Metro layout.
  2. There would be a couple of wheelchair spaces.
  3. Would a toilet be provided on the train? Crossrail puts them in the stations! Does Birmingham?
  4. Each car would be fully motored.
  5. Could each car have its own battery, so they handled their own regenerative braking efficiently?
  6. All the cars would be connected together by an electrical bus fed from the pantograph car.
  7. West Midlands Trains have said the new trains will be 90 mph units.

The capabilities are not unlike the current Class 323 trains.

The Aventras have advantages over the older trains.

  • They are articulated, which gives more space.
  • They are wider inside due to thin, strong car sides and underfloor heating.
  • Design of lobbies has improved.
  • A mixed traditional/metro interior can be used as in Crossrail’s Class 345 trains.

They could also be designed to a slightly longer length if required. But this might have operational and depot issues.

I expect Bombardier will have used every trick and dodge to get this order.

What Size Of Battery Is Needed To Handle Regenerative Braking?

I’ll do the calculation for one car with perhaps a hundred passengers running at 90 mph or 145 kph.

I’ll assume each passenger weighs 80 Kg with all their baggage, which gives a one-car mass of 43 tonnes.

The amount of energy in that one car is a very surprising figure of just 10 kWh.

How Far Could A Three-Car Aventra Go On Battery Power?

In an article in the October 2017 Edition of Modern Railways, which is entitled Celling England By The Pound, Ian Walmsley says this in relation to trains running on the Uckfield Branch.

A modern EMU needs between 3 and 5 kWh per vehicle mile for this sort of service.

The three-car Aventra will be an efficient train, but it will have features like air-conditioning, so I suspect that a figure of 4 kWh per car-mile will be achievable, if the following is done.

  • Air-conditioning is very intelligent and efficient.
  • The train is very well insulated.
  • All electrical equipment on the train like lights, toilets and doors are efficient.
  • Operation ensures batteries are fully charged before entering battery sections.
  • Pantograph operation will be intelligent to snatch a sneaky charge on a short length of electrification.
  • Regenerative braking energy is stored on the train.

3 kWh per car-mile may even be possible.

Suppose the battery in each car had a capacity of 75 kWh. This would give the following ranges with various energy consumption rates.

  • 3 kWh – 25 miles
  • 4 kWh – 19 miles
  • 5 kWh – 15 miles

It certainly is important to get the train as energy efficient as possible.

Increasing the battery capacity will increase the range proportionally.

This would mean that a very efficient train with a double-size battery could go fifty miles without wires.

Where Practically Could These Trains Run?

There are several possibilities.

Camp Hill Line

The Camp Hill Line is an obvious possibility.

A lot is said about the reopening in Future Plans in the Wikipedia entry for the line.

There has also been speculation in the railway press, that chords will be created to allow trains on the line to run directly into Birmingham Moor Street station.

Moor Street Station

If these trains were to run into Birmingham Moor Street station would the bay platforms at the station be electrified?

This would allow the trains batteries to be charged before returning along the Camp Hill Line.

But it would open up interesting possibilities.

With electrification at stations like Stratford-upon-Avon and Leamington to charge the batteries, could services South of Birmingham be run by three-car Aventras running on batteries?

Both |Stratford-upon-Avon and Leamington Spa are under forty miles by road from Birmingham,

I think it could be possible, but West Midlands Trains are acquiring a lot of diesel trains.

Extending Existing Electric Services

From May 2018, the electric services on the Cross City Line will run between Bromsgrove and Lichfield Trent Valley stations.

Could trains running on batteries extend services?

Conclusion

Three-car Aventras are an interesting possibility.

I think we’ll be seeing a lot of them around the UK.

October 19, 2017 Posted by | Travel | , , | 1 Comment

Bombardier and CAF To Make 413 Carriages For New West Midlands Franchise

The title of this post is the same as this article on Global Rail News.

This is said.

Future operator West Midlands Trains has made a £680 million order with Bombardier and CAF for 413 carriages.

Bombardier will manufacture 36 three-car and 45 five-car Aventra trains at its Derby site, while CAF will produce 12 two-car and 14 four-car Civity trains. In total, 107 new trains will be delivered.

The electric three-car Aventras will operate on metro services, the electric five-car units for outer suburban and long distance, while CAF’s DMUs will run on dedicated services to the towns and cities around Birmingham.

These are my thoughts on the various parts of the order.

The Three-Car Aventras

The thirty-six three-car Aventras will probably replace the twenty-six Class 323 trains, which lack wi-fi and other passenger-friendly features.

It should also be noted that the Aventra has a slightly unusual and innovative electrical layout.

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.

This was published six years ago, so I suspect Bombardier have refined the concept, which is probably more to do with spreading weight around the train for better dynamics than anything else!

Obviously for West Midlands Trains, there is no need for 750 VDC, but will there still be a pair of power cars?

So it looks like there may be a reorganisation of the electrical system in the trains.

A few other points.

  • I am surprised that some of the trains aren’t six-cars, as every other set of new trains seem to be single and double lengths.
  • According to Wikipedia, the trains will have end gangways.
  • The trains are air-conditioned and have free wi-fi and power sockets.

Hopefully, the full specification and Tops-number will be disclosed soon.

Are Batteries An Inherent Part Of The Operation Of Three Car Aventras?

Suppose each car in the train was a self-contained power car.

  • Each car could also have  a 75 kWh battery, which is the size of one on a New Routemaster hybrid bus.
  • Regenerative braking would be efficient as it would use the battery in the same car.
  • Batteries can be topped up using the 25 KVAC overhead wires.
  • Passenger services like power-points would be powered from the battery.

If we assume that each car needs 5 kW to do a mile, this would give the train a range away from the wires of 15 miles.

Would it be possible for trains to run on the Camp Hill Line and the proposed Camp Hill Chords into Birmingham Moor Street station solely using battery power?

I think it is possible and after the battery-powered trams on the Midland Metro, it’s another case of emphasising the B in Birmingham.

The Five-Car Aventras

These will probably be vaguely similar to the other two five-car Aventras; Class 701 and Class 720.

Differences highlighted in the various articles and Wikipedia include.

  • According to Wikipedia, the trains will have end gangways.
  • The trains will be 110 mph units.

Both are firsts for Aventras.

I don’t think it will be long before a train operator buys an Aventra capable of 125 mph.

The CAF Civity Trains

The CAF Civity are a mixture of two-car and four-car units and will be used to replace some older diesel multiple units and augment some of the more modern Class 170 and Class 172 trains.

Class 230 Trains

West Midlands Trains have also ordered three Class 230 trains for the Marston Vale Line.

The route has the following characteristics.

  • It is roughly twenty-four miles long.
  • Trains take just over forty minutes for the journey between Bletchley and Bedford stations.
  • There are plans to extend the service to Milton Keynes Central station.
  • It is a diesel island in a sea of electrified lines.

 

Wikipedia says this about the Infrastructure.

Apart from a short length of single track at both ends, the line is double track, and is not electrified (barring short lengths at either end). It has a loading gauge of W8 and a line speed of 60 miles per hour (97 km/h). The line’s signalling centre is at Ridgmont.

I would suspect that two trains are needed to provide an hourly service, so buying three trains gives a spare, that might augment the services at busy times.

The flexibility of the Class 230 trains will give a choice of operating modes.

  • Using 25 KVAC overhead electrification at the ends.
  • Using onboard diesel power.
  • Using batteries charged at the ends of the route.

I suspect that the most efficient will be a mix of all three.

The trains are also designed for remote servicing, so they could be based in a siding at Bedford, Bletchley or Wolverton and supported by a well-designed service vehicle and a fuel bowser.

Conclusions

West Midlands Trains seem to have gone for a sensible Horses-for-Courses solution.

I have a feeling that their concept for the Marston Vale Line will be used elsewhere.

 

October 18, 2017 Posted by | Travel | , , , , | 1 Comment

Govia Loses The West Midlands Rail Franchise

This article on the BBC is entitled London Midland loses West Midlands rail franchise.

The new lead partner in a company called West Midlands Trains is Abellio.

This page on the Government web site gives full details.

There is also this interactive map, which details changes by line.

The next few sections detail a few points.

Four Hundred New Carriages

West Midlands Trains are promising four hundred new carriages.

Currently, there are 476 carriages serving the routes they will be taking over. The trains that are modern include.

  • 77 x four-car Class 350 trains – 308 carriages – Built in 2004-2014
  • 17 x two-car Class 170 trains – 34 carriages – Built in 1999-2000
  • 6 x three-car Class 170 trains – 18 carriages – Built in 1999-2000

This is a total of 360 carriages.

This group probably lack wi-fi, which could be retrofitted.

It looks to me, that the West Midlands are going to be seeing a hell of a lot more trains.

Abellio should know what trains to buy, as they’ve just spent nearly a billion on new trains for Greater Anglia and are introducing a large fleet of Hitachi electric trains in Scotland.

Are we going to see a complete fleet change, as is happening with Greater Anglia and South Western Railway?

I think it will be very likely that the new train will be an Aventra or similar, with the following characteristics.

  • Based on four or five car units.
  • Ability to work in pairs.
  • Possibly some longer ones. of eight or ten cars for busy routes.
  • Walk-through design.
  • Large lobbies and wide doors.
  • Ability to stop at a station and get started quickly. Could save up to two minutes every stop.
  • 100 mph capability.
  • Some bi-mode or trains to work independently for perhaps thirty miles are needed.

They could be very similar to the Class 720 trains ordered by Greater Anglia or the Class 710 trains ordered by London Overground, if Aventras are chosen.

I will look at a simple example on the Cross-City Line  between Lichfield Trent Valley and Redditch stations.

This currently takes 83 minutes with twenty-two stops. This would probably give a three-hour round trip. So on a rough estimate, to provide this service on a two trains per hour (tph) basis, would require six trains or twelve, if each of the current Class 323 train is a pair of six-cars.

Running a five-car Aventra or similar, which would save over a minute a stop and would be faster, would probably bring the round trip time down to under two hours. So two tph, would need just four trains.

The capacity of the Aventra would be greater at over 800 passengers as opposed to 500 in the pair of Class 323 trains.

Birmingham To Rugeley Trent Valley

The electrification on the Chase Line is being extended to Rugeley Trent Valley and new electric services should start from May 2018.

Wolverhampton To Walsall Line

The Wolverhampton To Walsall Line is an oddity in that is electrified and doesn’t have a passenger service.

In the Wikipedia entry for the line under Future Plans, this is said.

The West Midlands Combined Authority have announced their intention to restore a passenger service to the line using either conventional trains or tram-trains. Along with new stations at Willenhall and Darlaston James Bridge.

So will these plans be implemented in the next few years?

Birmingham To Bromsgrove

The new electric trains would also be able to serve the newly electrified route to Bromsgrove station from May 2018.

Does The B In Birmingham Stand For Battery?

If Bombardier or Hitachi get their energy storage working, then the new trains would be able to continue to Worcester from Bromsgrove, as it’s only fourteen miles.

Birmingham is getting battery trams, so is it getting battery trains?

Battery trains would certainly be able to work the Camp Hill Line.

But it will be interesting to see if battery trains can sneak through on other routes in the centre of Birmingham.

The Snow Hill Lines

The Snow Hill Lines across Birmingham are the classic cross-city line that should be electrified, as you don’t want to have diesel trains in the centres of cities.

My thoughts.

  • In the current financial climate, large scale electrification is not going to happen.
  • Battery trains wouldn’t help, as there is no electrification with which to charge the batteries.
  • Traditional bi-modes aren’t much use either, as they’d run on diesel all the time.

The only alternative is probably more efficient diesel-electric hybrid trains that incorporate regenerative braking with batteries.

Could these trains be coupled with limited electrification in the centre around the Snow Hill Tunnel?

There’s a solution in there somewhere and I suspect that West Midlands Trains have used it.

Leamington To Nuneaton via Kenilworth And Coventry

This route via the new Kenilworth station will be getting an hourly service.

It’s only nineteen miles each way with scraps of electrification at Nuneaton and Coventry.

Could an Aventra or similar with batteries do this trip?

Conclusion

The West Midlands are getting a much better train service.

August 10, 2017 Posted by | Travel | , | Leave a comment