The Anonymous Widower

Thoughts On A Tri-Mode AT-300 Between Waterloo And Exeter

Note that in this post, I’m using the Class 802 train as an example of Hitachi’s AT-300 train.

In writing my post called What Would Be The Range Of A Tri-Mode Class 802 Train?, I realised that an efficient tri-mode train with electric, battery and diesel power could have a range of over a hundred miles.

Suppose a Class 802 train was built with the following characteristics, were designed for service on the West Of England Line.

  • Five cars, which would seat around 350 passengers.
  • Two diesel engines replaced with batteries of the same seven tonne weight.
  • At least 840 kWh or perhaps as much as 1,500 kWh of battery power could easily be installed.
  • One 700 kW diesel engine would be retained for electrification failure and to boost battery power.
  • All electrical equipment on the train will use the minimum amount of electricity.
  • Regenerative braking to batteries.
  • Aerodynamics would be improved, as I believe Hitachi are doing.
  • I believe that the train could have an energy consumption to maintain 100 mph on the West Of England Line around two kWh per vehicle-mile.

So what would be the range of a five-car train on just 840 kWh of batteries?

  • The train would consume 10 kWh per mile.

So this would give a range of 84 miles.

The diesel engine could be key.

  • At 100 mph, the train does a mile in thirty-six seconds.
  • In this time, the diesel engine can generate up to 7 kWh.
  • The train would need just 3 kWh per mile from the batteries to maintain 100 mph.

This would give a range of 280 miles,

This is more than enough for the 125 miles between Basingstoke and Exeter St. Davids stations.

Other people read books in the evening, I do puzzles and mathematical exercises.

In How Much Power Is Needed To Run A Train At 125 mph?, I calculated that a forty-year-old InterCity 125 needs 2.83 kWh per vehicle mile to maintain 125 mph. Surely, modern trains can halve that figure.

Suppose Hitachi, improve the aerodynamics and the energy consumption of the train, such that it is 1.5 kWh per vehicle mile, which is a figure I don’t consider impossible.

This would give a range with  840 kWh batteries of 112 miles.

With selective use of the diesel engine and a charging station at Exeter, this train could easily run between Waterloo and Exeter.

Passenger Capacity

The passenger capacity of the current Class 159 trains is 392 in two three-car trains working as a pair.

A five-car Class 802 train would probably seat 350 passengers in comfort.

Train Length

These are the train lengths.

  • A pair of three-car Class 159 trains are 156 metres long.
  • A five-car Class 802 train is 130 metres long.

So it would appear, there would be no platform length problems.


A tri-mode Class 802 train or AT-300 would appear to be ideal for Waterloo and Exeter.

Details of the AT-300 trains, that have been ordered by East Midlands Railway and the West Coast Partnership are not very comprehensive, but do say, the following.

  • Five-car trains will have four engines instead of three. Would they be smaller, with an added battery? Or will they use MTU Hybrid PowerPacks.
  • They will have a new nose. For better aerodynamics?

, But I believe they will make extensive use of battery traction to reduce the use of diesel.


November 18, 2019 - Posted by | Transport | , , , , ,


  1. Would the electrification come from the 3rd rail in this instance? Would that mean they are infact Quad Mode trains?

    Comment by angelmoon117 | November 18, 2019 | Reply

    • Yes! On both counts!
      Short lengths of third rail could also be installed in stations, so the train could use these to take a quick sip during a stop and for acceleration away!
      The Hitachi Class 395 trains, which work in Kent, are part of the same Hitachi A-train family and already have third rail capability.

      Comment by AnonW | November 18, 2019 | Reply

  2. It was surprising that replacing Class 159 trains was not part of the new franchise for SWR especially as the franchise changed hands and was in complete contrast to what happened on services out of Liverpool Street where even fairly new trains are to be replaced.

    Especially given these class 159 DMUs run on an otherwise electrified network especially at the London end of the route served.

    I notice that replacing a pair of Class 159s with a 5 car Class 802 means 42 fewer seats something that might cause controversy and reduces capacity for future growth.

    You mention installing short sections of 3rd rail to charge up batteries but it seems from the way extension of other 3rd rail routes to eliminate diesel islands has come up against the health and safety brigade then more 3rd rail looks impossible!

    SWR merges with GWR at the country end and so overhead electrification is likely in the longer term .
    If the new trains were both AC and DC they could operate into both Waterloo and Paddington Stations something that would be useful during disruption to services.

    Comment by Melvyn | November 18, 2019 | Reply

    • I think it was surprising too, that the Class 159 trains were not replaced. Especially, when you consider that it would make Waterloo a diesel-free station like Liverpool Street and now Kings Cross and Paddington after the introduction of Hitachi trains. The new trains ordered by East Midlands Railway and West Coast Rail will make St Pancras and Euston diesel-free, which must be a good thing. Just smell the air in Paddington these days.

      I use Greater Anglia a lot and with the exception of the Class 379 trains, the fleet was ld, tired and didn’t meet customers requirements. I do wonder, if there is something wrong with the Class 379 trains. Or perhaps, more likely, not the trains, but their leasing arrangements. Could they be expensive? Notice, that no-one seems to want them!

      It could be that they are only 100 mph trains, which probably would mean they would need to be updated to 110 mph for working to Corby of somewhere similar. I think the only use for these trains is as Airport specials or 100 mph battery trains perhaps for Southern. Does the leasing company want to not spend any money?

      It should also be noted that when all Greater Anglia’s new trains are delivered, they will only have three types of trains, as opposed to seven. They will also all be step-free between train and platform.

      You mention capacity of the AT-300. This will not be a problem, as the trains ca be lengthened by adding a trailer car in the middle. Like Aventras and Flirts, they are cut-and-paste.

      I am in Plyouth at the moment and come down in a Class 802 train via Newbury. The train was excellent running at 80-100 mph running on diesel, with not too much noise and vibration under my feet. But these trains would be much better with MTU PowerPacks or batteries.

      After I arrived in Plymouth, I went for a return trip to Newton Abbot on a Castle. It makes you realise how good the ride is, in an HST.

      If SWR and GWR are using the same train, then surely they could cooperate on maintenance, perhaps doing the heavy stuff at either North Pole or Plymouth.

      I can certainly see GWR buying more Hitachi trains to increase services and a Mark 2 with more efficient traction and aerodynamics might be better for South West services.

      I also suspect that the existing fleet will be able to be upgraded to the new specification. That would be a nice little earner for the company.

      Hitachi has not said anything about the new nose, but I suspect it will reduce the cruise power substantially. Could it also allow a gangway between the sets, which staff have told me is a nuisance?

      GWR don’t seem to do any splitting and joining, but it does appear than LNER will be doing a lot at Leeds to serve Brdford, Harrogate, Huddersfield and Skipton.

      Perhaps GWR could join and split Bedwin and Oxford services at Reading?

      Comment by AnonW | November 19, 2019 | Reply

      • You mention third-rail electrification. I feel that at a station with the platforms either side of the line and the two extra rails in the middle and only powered when the train is connected, is now possible and will satisfy the most most fervent member of the Health and Safety Taliban.
        I do wonder, if the Basingstoke and Exeter route will be swapped to GWR.
        It could be run by five-car GWR Class 802 trains. These might be ideal to combine with the Bedwyn service, splitting and joining at Reading.
        Remember, that when Crossrail opens and Paddington gets a second concourse at the country end, Paddington will be a much better connected station than Waterloo.
        Perhaps, that is why the 159s have not been replaced? Paddington would not need any more paths to add the second Exeter service and Waterloo would gain another path on a very busy route, with Waterloo going diesel-free. I also suspect that the current 802s would be faster to Exeter, than the 159s. The 802s wouldn’t need to be equipped with third-rail gear, as there’s no third-rail.

        Comment by AnonW | November 19, 2019

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