British Rail Class 93 (Stadler)

The British Rail Class 93 is a tri-mode locomotive built by Stadler Rail in Valencia. It is an evolution of the Class 88 bi-mode locomotive, which was built by Stadler for Direct Rail Services. Three different power sources are used to power the locomotive – 4,000 kW (5,400 hp) 25 kV AC overhead electric power, or a 900 kW (1,200 hp) diesel engine supplemented by a 400 kW (540 hp) battery – allowing the locomotive to be used on both electrified and non-electrified lines.

British Rail Class 93
Type and origin
Power typeElectro-diesel with battery
BuilderStadler Rail
(Stadler Rail Valencia SAU)[1]
ModelEuro Dual
Build dateJune 2022 – 2024
Specifications
Configuration:
 • UICBo′Bo′
Gauge4 ft 8+12 in (1,435 mm) standard gauge
Loco weight86 tonnes (85 long tons; 95 short tons)
Electric system/s25 kV 50 Hz AC overhead
Current pickup(s)Pantograph
Prime moverCaterpillar C32
Engine typeFour-stroke V12 diesel[2]
AspirationTwin-turbocharged[2]
Displacement32.1 L (1,959 cu in) total[2]
Performance figures
Maximum speed110 mph (180 km/h)
Power output
  • On AC electric supply:
    4,600 kW (6,200 hp)
  • Diesel engine:
    900 kW (1,200 hp)
  • Battery packs:
    400 kW (540 hp)
[3]
Tractive effort290 kN [4] (At low speeds)
Career
OperatorsRail Operations Group
Numbers93001–93010[5]
DispositionUnder testing

Rail Operations Group is the sole operator and ordered ten locomotives.

Development

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Background

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Since the phasing out of steam locomotives in the 1960s, the vast majority of Britain's freight trains have been powered by diesel locomotives.[6][7] During the late 2010s, as part of wider efforts to pursue carbon neutral operations, the Department for Transport (DfT) stated its long term goal of eliminating diesel-only traction from Britain's railways by 2040, despite only 46.5% of all lines being electrified.[6] However, due to a lack of government support for the rail freight sector, operators have traditionally faced difficulty in justifying sizeable capital investments such as new locomotives, thus many are between 25 and 50 years old as of 2020.[7]

Rationale

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Founded in 2015, Rail Operations Group (ROG) quickly took an interest in bi-mode propulsion technology as well as high-speed freight operations.[7] The company observed that rival operators made heavy use of the Class 66, a locomotive introduced in the mid-1990s, and that this would be the base line to innovate against in the locomotive-hauled freight market. ROG opted to work in conjunction with locomotive manufacturer Stadler Rail to develop a tri-mode high powered locomotive concept, which has since been assigned the designation of Class 93. The concept was first proposed during 2018.[7][8]

Development history

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In January 2021, ROG confirmed its order of 30 Class 93 locomotives, with the first ten deliveries scheduled for 2023.[9] Grand Union has proposed using Class 93s on its London Euston to Stirling services.[10]

During mid-2022, production of the fleet had commenced at Stadler's plant in Valencia.[11] On 1 July 2023, the first Class 93 was officially delivered to ROG; testing of the type was underway to support its future introduction to service.[12]

By February 2024, ten units had been built, but the order for 20 more units was uncertain.[5]

Specification

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The Class 93 locomotive is a derivative of the Class 88 electro-diesel and Class 68 diesel locomotives, both of which were built by Stadler.[7][13] As with Class 88 locomotives, Class 93s are designed as fast freight locomotives that use electric power while under the wires, but that are also capable of self-powered operations.[7] However, improving upon Class 88s – which when running in diesel mode produce a maximum of 710 kW (950 hp), and are thus mostly limited to 'last mile' operations – the Class 93 design includes both a 900 kW (1,200 hp) diesel engine and a 400 kW (540 hp) set of rechargeable battery packs.[7] The diesel engine is a turbocharged 12-cylinder Caterpillar C32, which conforms with the EU's Stage V emissions standards.[7]

The battery packs use lithium-titanium oxide chemistry and will have a liquid cooling solution, enabling rapid charge and discharge.[7][9] The battery packs can be charged either from the overhead AC supply via the onboard transformer, by the diesel engine when the full output is not needed for traction, or by using power reclaimed during regenerative braking.[7] As the battery packs are carried in the space used on Class 88 locomotives for the rheostatic brake resistor grids, Class 93s will not be equipped with rheostatic braking. Instead, they will use regenerative braking, when the batteries can accept charge, and/or friction braking.[7]

The Class 93 will have a top speed of 110 mph (180 km/h), and have a maximum of 1,300 kW (1,700 hp) of usable power when running in "hybrid" diesel mode with battery boost.[14][15] The batteries have a capacity of 80 kWh, sufficient for ten minutes of boost.[7] They can also be used to supply standalone traction power.[3]

Proposed use

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ROG intends to pair the locomotive with a new generation of freight wagons that would run at a maximum speed of 100 mph (160 km/h), comparable to that of contemporary passenger trains. Trains formed of such wagons would be easier to insert into timetables around and between existing passenger trains, increasing flexibility and potentially creating capacity for more freight trains on the national network.[7]

In addition to freight, the Class 93 has also been designed to accommodate the haulage of passenger stock, including a variable-height Dellner coupling and a three-step Westcode brake in addition to its conventional two-pipe air brake.[7]

Comparison with competing locomotives

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In comparison with the Class 66, the Class 93 can outperform it in various metrics.[7] The locomotive has a higher top speed and offers greater acceleration on electrified lines. It has far lower operating costs, consuming only a third of the fuel of a Class 66, along with lower track access charges due to its lower weight. ROG has postulated that it presents a superior business case, particularly for intermodal rail freight operations, while also being better suited for mixed-traffic operations as well.[7] Each locomotive has a reported cost of £4 million.[7]

Models

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In 2021, Revolution Trains announced it was in the early stages of developing a OO gauge model of the Class 93, using CAD data supplied by Stadler.[16][17]

See also

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References

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  1. ^ "Stadler and Rail Operations (UK) Limited sign a contract for the new Class 93 tri-mode locomotives" (PDF). Bussnang: Stadler Rail Group. 14 January 2021. Retrieved 19 January 2023.
  2. ^ a b c Cat C32 Locomotive Engine (PDF) (11-19 ed.). Caterpillar Inc. LEHR0022-01. Archived from the original (PDF) on 19 January 2023. Retrieved 19 January 2023.
  3. ^ a b "Class 93 locomotive project reaches a significant milestone with the completion of the first carbody". Derby: Rail Operations (UK) Ltd. 21 July 2022. Archived from the original on 5 August 2022. Retrieved 21 February 2023.
  4. ^ "Class 93 tri-mode locos on order". Rail Engineer. 21 April 2021. Retrieved 28 June 2023.
  5. ^ a b "ROG remains silent over delays to Class 93s". Network News. Rail Magazine. No. 1003. 21 February 2024. p. 24.
  6. ^ a b "Why rail electrification is key to keeping the UK's climate progress on track". Rail Engineer. Coalville: Rail Media Group. 2 September 2020.
  7. ^ a b c d e f g h i j k l m n o p q Shirres, David (1 September 2020). "Re-engineering Rail Freight". Rail Engineer. Coalville: Rail Media Group.
  8. ^ Devereux, Nigel (31 December 2018). "Rail Operations Group and Stadler in Tri-Mode Loco Plan". The Railway Magazine. Horncastle: Mortons Media Group.
  9. ^ a b Richard Clinnick (14 January 2021). "Rail Operations (UK) Ltd orders Class 93 tri-modes". Rail Magazine. Retrieved 12 February 2021.
  10. ^ "Grand Union plans 93s to Stirling". Modern Railways. No. 875. Stamford: Key Publishing. August 2021. p. 17.
  11. ^ Smith, Roger (22 July 2022). "Production of Class 93 locomotive fleet reaches significant milestone". Rail Advent. Retrieved 17 November 2022.
  12. ^ Clinnick, Richard (29 August 2023). "The future of UK traction arrives". therailwayhub.co.uk.
  13. ^ "Discontinuous electrification – repurposing existing rolling stock". London: IPEX Consulting. 30 September 2019. Retrieved 2 September 2020.
  14. ^ Clinnick, Richard (19 December 2018). "Rail Operations fuels its ambitions with tri-mode Class 93s". Rail Magazine. Peterborough: Bauer Consumer Media. Retrieved 1 February 2023.
  15. ^ Fender, Keith (6 November 2019). "Locos go bi- and tri-mode!". Rail Engineer. Coalville: Rail Media Group. Archived from the original on 8 December 2019. Retrieved 1 February 2023.
  16. ^ "ROG 93 Revealed". Revolution Trains. 5 May 2022. Retrieved 6 May 2022.
  17. ^ "Revolution goes tri-mode for class 93 locos with Rail Operations Group". 24 February 2021. Archived from the original on 18 January 2022. Retrieved 6 May 2022.