The Anonymous Widower

UK’s First 100mph Battery-Diesel Hybrid Train Enters Passenger Service

The title of this post, is the same as that of this article on ITV.

These are the first three paragraphs.

The UK’s first 100mph battery-diesel hybrid train is entering passenger service to cut carbon emissions and boost air quality.

It was developed by adding a powerful battery to a 20-year-old diesel train to reduce fuel consumption and CO2 emissions by 25%, according to owner Porterbrook.

The firm added that the two-carriage train, named HybridFLEX, also provides a 75% decrease in noise and a 70% decrease in nitrogen oxide.

The battery-diesel hybrid transmission is from MTU, who are a Rolls-Royce company and they go further with this press release which is entitled World Premiere: MTU Hybrid PowerPack From Rolls-Royce Enters Passenger Service.

This is the first paragraph.

Rolls-Royce, Porterbrook and Chiltern Railways are making rail history together with a climate-friendly world premiere: A hybrid diesel-battery-electric train that reduces CO2 emissions by up to 25% entered passenger service in the UK today for the first time. The so-called HybridFLEX train is powered by two mtu Hybrid PowerPacks and is operated by Chiltern Railways on the route between London Marylebone and Aylesbury. Together with the leasing company Porterbrook and Chiltern Railways, Rolls-Royce has converted a Class 168 DMU into the HybridFLEX train. The partners are proving that existing rail vehicles can be used in a climate-friendly way without the need to install complex and expensive new infrastructure. It is the world’s first regular passenger operation with mtu Hybrid PowerPacks, of which 13 have already been ordered.

This is significant for the railways of the UK.

The train that has been converted is a Class 168 train, which itself had been converted from a Class 170 train, when it transferred to Chiltern Railways in 2016.

I think this means that all Bombardier Turbostars in Classes 168, 170, 171 and 172 can probably be fitted with MTU Hybrid PowerPacks.

That is the following numbers of trains and cars.

  • Class 168 – 28 trains – 86 cars
  • Class 170 – 139 trains – 372 cars
  • Class 171 – 20 trains – 56 cars
  • Class 172 – 39 trains – 93 cars


  1. This totals to 226 trains and 607 cars.
  2. As each car has an engine, this will be an order of 607 PowerPacks, if all trains were to be converted.

This could certainly help to meet the Government’s aim of getting rid of all diesel only trains by 2040.

Can The CAF Civities Be Converted?

There are three Classes of CAF Civity diesel multiple units; 195, 196 and 197, all of which have Rolls-Royce MTU engines.

Could these be converted to hybrid operation by the swapping of the current diesel engines for MTU Hybrid PowerPacks?

I would suspect they could, as the CAF Civity trains might have been designed after MTU disclosed plans of the MTU Hybrid PowerPack to train builders prior to its announcement in September 2018.


MTU Hybrid PowerPacks could go a long way to eliminating diesel-only trains on UK railways. They could even run the diesels on Hydrotreated Vegetable Oil (HVO) to lower their carbon-footprint further.


February 10, 2022 - Posted by | Transport/Travel | , , , , , , , , , , , , , , ,


  1. Having done the engineering conversion on the 168 they now have the solution for the Voith transmission vehicles. That also means they have the technical, risk and operational engineering approvals and a revised Safety Case to satisfy the re-equipment of the Class 168,170 and 171. The Class 172 already has the conventional MTU power pack so like the Class 19X it’s broadly a plug and play exercise.
    At the time the HybridFLEX was announced publicly in September 2018, the orders for the 19X’s was well underway and as we know MTU with limited running on the shores of Lake Constance had insufficient operating experience to warrant TfW, Northern and West Midlands delaying delivery of the 195, 196, 196.
    I wouldn’t mind betting that conversion of Class 19X to HybridFLEX will be done on favourable terms.

    Comment by fammorris | February 10, 2022 | Reply

    • With a product, that could be very beneficial to customers, a company will probably warn those customers about what is happening. So I wouldn’t be surprised that MTU told CAF about the hybrid PowerPack, so that CAF didn’t train a product that couldn’t be upgraded to the Hybrid PowerPacks. Or better still, MTU have designed the Hybrid PowerPacks to be able to be fitted in the same place as any of their engines. It does appear that the battery packs can be separate from the diesels, so perhaps MTU designed a Hybrid PowerPack to fit all or at least most of their existing engine installations.

      If you have a diesel-electric MTU installation like a Class 43 power car, I wonder if MTU have designed a replacement for these.

      Comment by AnonW | February 10, 2022 | Reply

      • I’m sure CAF knew about MTU’s aspirations for the HybridFLEX.I’m not sure if you’re questioning whether MTU have a diesel electric hybrid for ra

        Comment by fammorris | February 11, 2022

  2. Fabulous but just gone with it and convert the rest of the fleets to demonstrate they are serious about decarbonising rail.

    Comment by Nicholas Lewis | February 10, 2022 | Reply

    • There must be about fifty of these trains that are going to change operator, so surely, this would be the time to change the power system, as the trains will probably have a heavy maintenance anyway.

      As to the Class 43’s most are now running on trains in tourist areas. I’m sure Rolls Royce MTU would love all the publicity of quiet iconic locomotives displaying modern technology.

      I have joked that I’d like to see a Class 43 converted to hydrogen, so that it could set a speed record for a hydrogen train. One converted to hybrid could set the speed record for hybrid vehicles.

      Comment by AnonW | February 10, 2022 | Reply

      • You may get elements of the heavy overhaul but I wouldn’t assume they will get everything in what used to be known as a C4 Exam (overhaul of bogies and underframe equipment), certainly C6 Exams (structure/body overhauls including door overhauls and exterior wrapping, plus technical modifications to systems and interior refurbishment) became as rare as hen’s teeth. Today it’s more condition based maintenance.

        Comment by fammorris | February 11, 2022

  3. I would contrast this with Germany, which has spent the past 4 years running extensive trials of battery and hydrogen trains which get rid of diesel altogether, and which has a government committed to substantiallly increasing track electrification.

    No prizes for guessing which country I think has the better strategy.

    Comment by Peter Robins | February 11, 2022 | Reply

    • I rode a battery-electric train to Harwich in 2015. Where are the battery-electric Electrostars for Uckfield? In that time we’ve had several different transport ministers. I think there’s an Oxford-educated civil servant somewhere blocking it because in his mind he feels battery-electric trains won’t work. Or is it a shortage of train modification capacity? There must be 379s sitting in sidings as well! The government is encouraging batteries for cars and grid stabilisation so I don’t think it’s at the top. Sort it!

      Comment by AnonW | February 11, 2022 | Reply

      • GA have placed all the 379s into warm store so would have been an ideal opportunity to have fitted batteries and shoegear so they could use them in Southern -won’t happen of course

        Comment by Nicholas Lewis | February 11, 2022

  4. The 379s appear to be owned by Akiem, who are French. I’m certain other leasing companies would convert them into dual-voltage 110 mph battery-electric trains.

    Comment by AnonW | February 11, 2022 | Reply

    • They were Rock Rail until Akiem bought them. Lease costs were alot higher than comparable units but lease was up and suspect DofT are playing chicken with them to get the rate down.

      Akiem are part owned by SNCF

      Comment by Nicholas Lewis | February 11, 2022 | Reply

    • Akiem is owned in equal parts by Transport et Logistique Partenaires SA (TLP, an SNCF Participations subsidiary holding company) and Eurotraction, an investment fund managed by DWS, an international asset manager, whose majority shareholder is Deutsche Bank.
      You wonder why Akiem bought out Macquarie in 2020 when it must have been clear that with the Class 379s coming off lease they would likely have trouble leasing them to another operator.

      Comment by fammorris | February 11, 2022 | Reply

      • I would imagine they factored that in when they agreed the price and potentially they got them cheap and can now set a more realistic lease rate to entice DofT to release them.

        Comment by Nicholas Lewis | February 11, 2022

      • You’re probably right that they knew about the fragility of the leasing situation over the 379s, but until things change under whatever GBR turns out to be, DfT only have an informal, though persuasive influence over future leasing prospects. After all since the pandemic established itself the Treasury have effectively been paying for the Railway.
        Akiem were trying to realign their portfolio towards European freight at the time the takeover was announced in February 2020 (before the Covid pandemic), so I suspect they were more interested in the 137 locomotives which were part of the deal. That gave them EMD/Wabtec Class 66s, Bombardier Traxx, Alstom Primas, GE/Progress Rail 311Ds, GE Class 70 locos along with 110 wagons. The Bombardier Class 379 EMUs and the Stadler GTW DMUs in the Netherlands were probably not the focus of the purchase.

        Comment by fammorris | February 11, 2022

  5. I do wonder if the original plan was to use some of them to Corby, as both GA and EMR are Abellio, but in the EMR choose the 360s. Perhaps it was just cost?

    Comment by AnonW | February 11, 2022 | Reply

  6. […] post is to try to get some logic into everybody’s comments on UK’s First 100mph Battery-Diesel Hybrid Train Enters Passenger Service, which are about the Class 379 […]

    Pingback by The Future Of The Class 387 And Class 379 Trains « The Anonymous Widower | February 11, 2022 | Reply

  7. It seems thar Stadtler FLIRTS are already available as a 100mph plus hybrid, just not in the UK, not clear how that would change the length of the train especially 3 carrriage consists, or one of the two diesel motors is removed from the power pack.

    Comment by MilesT | February 12, 2022 | Reply

    • Interesting that the 755 have 4 deutz engines in 4 car but only two in a 3 car! What was the logic i wonder.

      Comment by Nicholas Lewis | February 12, 2022 | Reply

    • In the early days of the introduction of the Class 755 trains, I had a chat with one of the drivers, who had been to Switzerland. He had been told that the train had been designed for 125 mph.

      Having done hundreds of trips on the Great Eastern Main Line in Mark 3 coaches hauled by Class 90 locomotives, including two between London and Norwich in ninety minutes and several in new Class 745 trains, I can confirm that the ride of the Swiss flyers is up there with the 125 mph Mark 3 coach. Other Flirt versions are certified for 125 mph.

      LNER are looking for ten extra trains. I don’t think Stadler will hold back of bidding a version of the excellent FLIRTs for this order.

      Comment by AnonW | February 12, 2022 | Reply

  8. […] Conversion of Bombardier Turbostars to hybrid operation. I covered this in UK’s First 100mph Battery-Diesel Hybrid Train Enters Passenger Service. […]

    Pingback by Rolls-Royce And Porterbrook Agreement Will Drive Rail Decarbonisation « The Anonymous Widower | February 14, 2022 | Reply

  9. The first 197 entered service today There have been quite a few test/training runs out of Chester, with several units sat in the sidings overnight. The depot is now labelled CAF. So I’d expect them to start running services from/through there before too long.

    TfW shows no interest in hybrid operation though! And AFAIK the Vivarail units still aren’t operational on Wrexham-Bidston.

    Interesting what the article says about corrosion on the Coradias. 20 years isn’t a long time for a train.

    Comment by Peter Robins | November 14, 2022 | Reply

    • Well if the Class 175 bodyshell is corroding then so too is the Class 180, as both bodyshells were built in Alstom (now Stadler’s) plant in Barcelona. I suppose it depends what is corroding since we’ve had enough stress corrosion of bogies on nearly new CAF and Hitachi.
      I feel that for too long the rail industry had chosen to overlook routine inspection of body structures just think back to ADtranz Networker Classic project and the disastrous levels of corrosion discovered that led to it’s cancellation.
      Just what is delaying the introduction of the Vivarail units, I can’t understand what’s stopping them.

      Comment by fammorris | November 14, 2022 | Reply

  10. Thanks! James

    Comment by AnonW | November 14, 2022 | Reply

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: