
Electro-diesel locomotive
Encyclopedia
An Electro-diesel locomotive (also referred to as dual-mode locomotive) is powered either from an electricity supply (like an electric locomotive
) or by using the onboard diesel engine
(like a diesel-electric locomotive). For the most part, these locomotives are built to serve regional, niche markets with a very specific purpose.
s are used to provide continuous journeys along routes that are only partly electrified without a change of locomotive, extensive running of diesel under the wires or where diesel engines are banned. They may be designed or adapted mainly for electric use, mainly for diesel use or to work well as either electric or diesel.
This is effectively an electric locomotive
with a relatively small auxiliary diesel engine intended only for low-speed or short-term operation (e.g. British Rail Class 73
). Some of these, such as the British Rail Class 74
, were converted from electric locomotives. The Southern Region of British Railways
used these locomotives to cross non-electrified gaps and to haul boat trains which used tramways at the ports of Southampton
and Weymouth.
with auxiliary electric motors (or connections to the existing traction motors), usually operating from 750 V DC third rail
where non-electric traction is banned (e.g. EMD FL9
). The primary function for these models is to provide a one-seat ride between diesel territory and the New York City
terminals of Grand Central Terminal
and Penn Station, which have ordinances prohibiting locomotives from emitting smoke within their tunnels. Once out of the tunnels, the third-rail shoes are retracted and operation is as a normal diesel locomotive.
). These will normally operate under pure electric traction where possible, and use the diesel engines to extend the journeys along non-electrified sections which would not be cost effective to electrify. They may also be used on long cross-country routes to take advantage of shorter sections of electrified main lines.
has built dual-mode variants of its AGC
series for the French
operator SNCF
; the electricity is collected by means of a pantograph
.
s and diesel motors; these locomotives were actually multiple-units, with distinct electric, diesel, and motor sections. These included:
in 1940 but was not a success. Only two other types have been built. In both cases, their electricity source was a 750 V
DC
third rail
.
The Hitachi Super Express trains proposed for the electrification of the Great Western Main Line
have a variant able to operate in bi-mode as an electro-diesel trainset. This would enable intercity services from Paddington Station
to continue beyond Cardiff Central railway station
, currently the western limit of the proposed electrification scheme.
Bombardier has plans, apparently known as Operation Thor or Project Thor, to convert 500 existing diesel multiple units (DMUs) into electro-diesel multiple units (EDMUs).
Whilst exact details are unclear, one source specifies that these would involve their Voyager family DEMUs
, and entail the construction of additional intermediate cars with a pantograph
and a transformer which would feed power into the traction motors of the existing diesel-electric cars when running off overhead lines
.
Several primarily diesel locomotive types and a multiple-unit have been built to operate off a 750 VDC third rail
into the New York City
terminals of Grand Central Terminal
and Penn Station:
Additionally, a full dual-mode 200/160 km/h locomotive for use with catenary is now under test.
is a 3kV DC electro-diesel locomotive designed by Consortium under the leadership of Siemens
and built by Union Carriage and Wagon (UCW) in Nigel, Gauteng
, South Africa
. Between November 1992 and 1993 fifty of these locomotives were placed in service by Spoornet, formerly the South African Railways (SAR) and later renamed Transnet Freight Rail (TFR). The diesel engine enables the locomotive to shunt on unelectrified sidings.
A specialized type of electro-diesel locomotive is the hybrid locomotive. Here, the electricity comes from a battery (charged by the diesel engine) rather than an external supply. An example is the Green Goat switcher
.
Electric locomotive
An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device...
) or by using the onboard diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
(like a diesel-electric locomotive). For the most part, these locomotives are built to serve regional, niche markets with a very specific purpose.
Overview
Electro-diesel locomotives and electro-diesel multiple unitMultiple unit
The term multiple unit or MU is used to describe a self-propelled carriages capable of coupling with other units of the same or similar type and still being controlled from one driving cab. The term is commonly used to denote passenger trainsets consisting of more than one carriage...
s are used to provide continuous journeys along routes that are only partly electrified without a change of locomotive, extensive running of diesel under the wires or where diesel engines are banned. They may be designed or adapted mainly for electric use, mainly for diesel use or to work well as either electric or diesel.
Primarily electric

Electric locomotive
An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device...
with a relatively small auxiliary diesel engine intended only for low-speed or short-term operation (e.g. British Rail Class 73
British Rail Class 73
The British Rail Class 73 is a United Kingdom model of electro-diesel locomotive. The type is unusual in that it can operate from a 750 V DC third-rail or an on-board diesel engine to allow it to operate on non-electrified routes...
). Some of these, such as the British Rail Class 74
British Rail Class 74
British Rail Class 74 was an electro-diesel locomotive that operated on the Southern Region of British Railways, rebuilt from redundant Class 71 locomotives in the late 1960s...
, were converted from electric locomotives. The Southern Region of British Railways
Southern Region of British Railways
The Southern Region was a region of British Railways from 1948. The region ceased to be an operating unit in its own right in the 1980s and was wound up at the end of 1992. The region covered south London, southern England and the south coast, including the busy commuter belt areas of Kent, Sussex...
used these locomotives to cross non-electrified gaps and to haul boat trains which used tramways at the ports of Southampton
Southampton
Southampton is the largest city in the county of Hampshire on the south coast of England, and is situated south-west of London and north-west of Portsmouth. Southampton is a major port and the closest city to the New Forest...
and Weymouth.
Primarily diesel
This is effectively a diesel locomotiveDiesel locomotive
A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...
with auxiliary electric motors (or connections to the existing traction motors), usually operating from 750 V DC third rail
Third rail
A third rail is a method of providing electric power to a railway train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost...
where non-electric traction is banned (e.g. EMD FL9
EMD FL9
The EMD FL9 was a dual-power electro-diesel locomotive, capable of diesel-electric operation and of operation as an electric locomotive powered from a third rail...
). The primary function for these models is to provide a one-seat ride between diesel territory and the New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
terminals of Grand Central Terminal
Grand Central Terminal
Grand Central Terminal —often incorrectly called Grand Central Station, or shortened to simply Grand Central—is a terminal station at 42nd Street and Park Avenue in Midtown Manhattan in New York City, United States...
and Penn Station, which have ordinances prohibiting locomotives from emitting smoke within their tunnels. Once out of the tunnels, the third-rail shoes are retracted and operation is as a normal diesel locomotive.
Full dual-mode
With modern electronics, it is much easier to construct (or adapt) an electro-diesel locomotive or multiple-unit which is equally at home running at high speeds both under the wires and under diesel power (e.g. SNCF Class B 82500SNCF Class B 82500
The B 82500 is a class of hybrid multi-system electro-diesel multiple units built by Bombardier for SNCF. It is capable of operating on diesel power, and under and electrification. Unlike other models in the AGC lineup, this class is available only as 4-car sets, not 3-car ones...
). These will normally operate under pure electric traction where possible, and use the diesel engines to extend the journeys along non-electrified sections which would not be cost effective to electrify. They may also be used on long cross-country routes to take advantage of shorter sections of electrified main lines.
France
BombardierBombardier Transportation
Bombardier Transportation is the rail equipment division of the Canadian firm, Bombardier Inc. Bombardier Transportation is one of the world's largest companies in the rail-equipment manufacturing and servicing industry. Its headquarters are in Berlin, Germany....
has built dual-mode variants of its AGC
Autorail à Grande Capacité
The Autorail à Grande Capacité is a category of multiple unit trains built by the Canadian train manufacturer Bombardier at Crespin for the French rail operator SNCF...
series for the French
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
operator SNCF
SNCF
The SNCF , is France's national state-owned railway company. SNCF operates the country's national rail services, including the TGV, France's high-speed rail network...
; the electricity is collected by means of a pantograph
Pantograph (rail)
A pantograph for rail lines is a hinged electric-rod device that collects electric current from overhead lines for electric trains or trams. The pantograph typically connects to a one-wire line, with the track acting as the ground wire...
.
- B 81500SNCF Class B 81500The B 81500 is a class of hybrid railway multiple units built by Bombardier for SNCF and used on the TER network. It is capable of operating on diesel power as well as a 1.5 kV DC electricity supply...
– multiple unitMultiple unitThe term multiple unit or MU is used to describe a self-propelled carriages capable of coupling with other units of the same or similar type and still being controlled from one driving cab. The term is commonly used to denote passenger trainsets consisting of more than one carriage...
trains using 1.5 kV DC catenary, in service since 2005 - B 82500SNCF Class B 82500The B 82500 is a class of hybrid multi-system electro-diesel multiple units built by Bombardier for SNCF. It is capable of operating on diesel power, and under and electrification. Unlike other models in the AGC lineup, this class is available only as 4-car sets, not 3-car ones...
– multiple unit trains using both 1.5 kV DC and 25 kV ACAlternating currentIn alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
catenary, currently still being built
Germany
- Gmeinder class 478.6 diesel and 750 V DC third-rail (bottom contact).
- Voith Futura, a concept locomotive rebuilt from DB 240 002DB Class 240The DB Class 240 are a class of Co'Co' diesel electric locomotives which were produced in the 1980s by MaK in collaboration with Krupp and ABB as DE 1024 as prototypes/technology demonstrators for a possible future order from the Deutsche Bundesbahn....
. - Bombardier TRAXXTRAXXBombardier TRAXX is a modular product platform of electric and Diesel-electric mainline locomotives built by Bombardier Transportation, built in both freight and passenger variants...
"Last Mile Diesel", mainly electric. Orders signed 2010, to be delivered probably 2012.
Russia
In Russia, a number of electro-diesels were built which had both pantographPantograph (rail)
A pantograph for rail lines is a hinged electric-rod device that collects electric current from overhead lines for electric trains or trams. The pantograph typically connects to a one-wire line, with the track acting as the ground wire...
s and diesel motors; these locomotives were actually multiple-units, with distinct electric, diesel, and motor sections. These included:
- ED16 (ЭД16), ED18 (ЭД18), and TEU1 (ТЭУ1) narrow gauge models
- OPE1 (ОПЭ1), OPE2 (ОПЭ2), NP1 (НП1), PE2(M) (РЭ2(М)), and EL20 standard-gauge locomotives used mostly in quarriesQuarryA quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...
Spain
- FEVEFEVEFEVE is a state-owned Spanish railway company, which operates most of Spain's of metre gauge railway.-History:...
1.900 Series, 1500 V DC overhead wires. This series is a rebuild of FEVE 1.000 Series locomotive.
- CAFConstrucciones y Auxiliar de FerrocarrilesConstrucciones y Auxiliar de Ferrocarriles is a rail equipment manufacturer based in Beasain in the Basque Country, Spain. Equipment manufactured by CAF includes light rail vehicles, rapid transit trains, railroad cars and locomotives, as well as variable gauge axles that can be fitted on any...
Bitrac 3600, 3000 V DC overhead wires. October 2007 order for 9 freight Co-Co locomotives. Available in Bo-Bo and Co-Co wheel configuration, 1435 or gauge, and as freight or passenger versions of 120 kilometre per hour maximum speeds respectively.
Switzerland

- Rhaetian Railway Gem 4/4Rhaetian Railway Gem 4/4The Rhaetian Railway Gem 4/4 is a two member class of metre gauge Bo'Bo' electro-diesel locomotives operated since 1968 by the Rhaetian Railway , which is the main railway network in the Canton of Graubünden, Switzerland....
, 1000 V DC overhead wires (Bernina RailwayBernina RailwayThe Bernina Railway is a single track metre gauge railway line forming part of the Rhaetian Railway . It links the spa resort of St. Moritz, in the Canton of Graubünden, Switzerland, with the town of Tirano, in the Province of Sondrio, Italy, via the Bernina Pass...
) - SBBSBB-CFF-FFSSwiss Federal Railways and SFR are not in official use) is the national railway company of Switzerland headquartered in Bern. Formerly a government institution, it is since 1999 a special stock corporation with all shares held by the Swiss Confederation or the Swiss cantons...
Tem346 shunters (see image). - SBBSBB-CFF-FFSSwiss Federal Railways and SFR are not in official use) is the national railway company of Switzerland headquartered in Bern. Formerly a government institution, it is since 1999 a special stock corporation with all shares held by the Swiss Confederation or the Swiss cantons...
Eem923 shunters using both 15kV 16·7Hz and 25kV 50Hz overhead wires and a 360 kW auxiliary diesel engine are on order from Stadler Winterthur.
United Kingdom
An experimental electro-diesel locomotive, DEL120, was built by London UndergroundLondon Underground diesel locomotives
Diesel locomotives have seen limited use on the London Underground, largely because exhaust gases cannot be discharged when the vehicles are working in tunnels. A prototype diesel engine was built in 1939 from two 1915 stock motor cars, which was expected to be part of a batch of ten, but...
in 1940 but was not a success. Only two other types have been built. In both cases, their electricity source was a 750 V
Volt
The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
DC
Direct current
Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
third rail
Third rail
A third rail is a method of providing electric power to a railway train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost...
.
- British Rail Class 73British Rail Class 73The British Rail Class 73 is a United Kingdom model of electro-diesel locomotive. The type is unusual in that it can operate from a 750 V DC third-rail or an on-board diesel engine to allow it to operate on non-electrified routes...
, dating from 1962 – the more successful design, with some still in regular use. They have lower power output in the diesel mode. - British Rail Class 74British Rail Class 74British Rail Class 74 was an electro-diesel locomotive that operated on the Southern Region of British Railways, rebuilt from redundant Class 71 locomotives in the late 1960s...
– rebuilt from British Rail Class 71British Rail Class 71The British Rail Class 71 was an electric locomotive used on the Southern Region of British Railways, unlike most other Southern Region electric locomotives they could not operate away from the electrified system.- History :As part of the BTC Modernisation Plan of 1955, twenty-four electric...
electric locomotives in 1967 and withdrawn by 1977.
The Hitachi Super Express trains proposed for the electrification of the Great Western Main Line
Great Western Main Line
The Great Western Main Line is a main line railway in Great Britain that runs westwards from London Paddington station to the west of England and South Wales. The core Great Western Main Line runs from London Paddington to Temple Meads railway station in Bristol. A major branch of the Great...
have a variant able to operate in bi-mode as an electro-diesel trainset. This would enable intercity services from Paddington Station
Paddington station
Paddington railway station, also known as London Paddington, is a central London railway terminus and London Underground complex.The site is a historic one, having served as the London terminus of the Great Western Railway and its successors since 1838. Much of the current mainline station dates...
to continue beyond Cardiff Central railway station
Cardiff Central railway station
Cardiff Central railway station is a major railway station on the South Wales Main Line in Cardiff, Wales.It is the largest and busiest station in Wales and one of the major stations of the British rail network, the tenth busiest station in the United Kingdom outside of London , based on 2007/08...
, currently the western limit of the proposed electrification scheme.
Bombardier has plans, apparently known as Operation Thor or Project Thor, to convert 500 existing diesel multiple units (DMUs) into electro-diesel multiple units (EDMUs).
Whilst exact details are unclear, one source specifies that these would involve their Voyager family DEMUs
Bombardier Voyager family
The Voyager series is a group of express diesel-electric multiple-unit trains built by Bombardier Transportation for service on the UK railway network.-Class 220:...
, and entail the construction of additional intermediate cars with a pantograph
Pantograph (rail)
A pantograph for rail lines is a hinged electric-rod device that collects electric current from overhead lines for electric trains or trams. The pantograph typically connects to a one-wire line, with the track acting as the ground wire...
and a transformer which would feed power into the traction motors of the existing diesel-electric cars when running off overhead lines
Overhead lines
Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains at a distance from the energy supply point...
.
United States

- GE three-power boxcabGE three-power boxcabThe GE three-power boxcabs were early electro-diesel hybrid switcher locomotives. General Electric built the chassis and running gear, generator, motors and controls, and Ingersoll Rand provided the diesel engine...
a switcher locomotive model built in 1930, also capable of operating as a battery locomotive retired from service.
Several primarily diesel locomotive types and a multiple-unit have been built to operate off a 750 VDC third rail
Third rail
A third rail is a method of providing electric power to a railway train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost...
into the New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
terminals of Grand Central Terminal
Grand Central Terminal
Grand Central Terminal —often incorrectly called Grand Central Station, or shortened to simply Grand Central—is a terminal station at 42nd Street and Park Avenue in Midtown Manhattan in New York City, United States...
and Penn Station:
- Baldwin RP-210Baldwin RP-210The RP-210 was a streamlined, locomotive built in 1956 by Baldwin-Lima-Hamilton, specifically to operate with the lightweight, all aluminum, Train-X train produced by Pullman Car Company...
– primarily diesel-hydraulic, third-rail electric mode for short-term use only; these have been retired from passenger service. - Roger WilliamsRoger Williams (train)-See also:*Baldwin RP-210, a lightweight train locomotive built for the New Haven's Dan'l Webster train.*Fairbanks-Morse P-12-42, a lightweight train locomotive built for the New Haven's John Quincy Adams train....
streamlined, six car, lightweight, DMU passenger train, built by the Budd CompanyBudd CompanyThe Budd Company is a metal fabricator and major supplier of body components to the automobile industry, and was formerly a manufacturer of stainless steel passenger rail cars during the 20th century....
in 1956 for the New York, New Haven and Hartford RailroadNew York, New Haven and Hartford RailroadThe New York, New Haven and Hartford Railroad , was a railroad that operated in the northeast United States from 1872 to 1968 which served the states of Connecticut, New York, Rhode Island, and Massachusetts...
– primarily diesel-hydraulic, third-rail electric mode for short-term use only; this has been retired from passenger service. - Fairbanks Morse P-12-42FM P-12-42The P-12-42, also known as the Speed Merchant, was a streamlined, locomotive built between 1957–1958 by Fairbanks-Morse, specifically to operate on each end of the Talgo train produced by American Car and Foundry...
– primarily diesel-electric, third-rail electric mode for short-term use only; these have been retired from passenger service. - EMD FL9EMD FL9The EMD FL9 was a dual-power electro-diesel locomotive, capable of diesel-electric operation and of operation as an electric locomotive powered from a third rail...
– primarily diesel-electric, third-rail electric mode for short-term use only; these have been retired from passenger service.
- P32AC-DM – dual-mode version of the GE Genesis, electric mode is only used for a few miles of travel.
- EMD DM30AC – specific to the Long Island Rail RoadLong Island Rail RoadThe Long Island Rail Road or LIRR is a commuter rail system serving the length of Long Island, New York. It is the busiest commuter railroad in North America, serving about 81.5 million passengers each year. Established in 1834 and having operated continuously since then, it is the oldest US...
.
Additionally, a full dual-mode 200/160 km/h locomotive for use with catenary is now under test.
- BombardierBombardier TransportationBombardier Transportation is the rail equipment division of the Canadian firm, Bombardier Inc. Bombardier Transportation is one of the world's largest companies in the rail-equipment manufacturing and servicing industry. Its headquarters are in Berlin, Germany....
ALP-45DPALP-45DPThe ALP-45DP is a dual-mode locomotive currently being built by Bombardier Transportation. It was unveiled to the public on September 21, 2010 at Innotrans 2010.-New Jersey Transit:...
- 36 locomotives are on order by New Jersey TransitNew Jersey TransitThe New Jersey Transit Corporation is a statewide public transportation system serving the United States state of New Jersey, and New York, Orange, and Rockland counties in New York State...
, to bridge gaps between non-electrified and electrified sections of track into New York Penn Station.
Canada
- Bombardier ALP-45DPALP-45DPThe ALP-45DP is a dual-mode locomotive currently being built by Bombardier Transportation. It was unveiled to the public on September 21, 2010 at Innotrans 2010.-New Jersey Transit:...
- 20 locomotives are on order for the Repentigny-Mascouche Line (AMT)Repentigny-Mascouche Line (AMT)The Repentigny-Mascouche Line. is a commuter rail line, proposed to be operated in the Greater Montreal Quebec, Canada area, by the Agence métropolitaine de transport, or AMT , the umbrella organization that plans, integrates, and coordinates public transportation services across this...
. It is a joint order with the New Jersey TransitNew Jersey TransitThe New Jersey Transit Corporation is a statewide public transportation system serving the United States state of New Jersey, and New York, Orange, and Rockland counties in New York State...
order above. They will provide a through journey on this mostly un-electrified new line, which joins an existing electrified commuter line to access Montreal's Central Station through the poorly ventilated, electric only Mount Royal TunnelMount Royal TunnelThe Mount Royal Tunnel is a railway tunnel located in Montreal, Quebec, Canada. It connects the city's Gare Centrale/Central Station, located downtown, with the north side of the Island of Montreal and Laval, passing through Mount Royal. Since 1995, the only trains using the tunnel are commuter...
.
South Africa
The South African Class 38-000South African Class 38-000
Between 1992 and 1994 Spoornet placed fifty Class 38-000 locomotives in service. They are still the only dual powered electro-diesel locomotives in use by Transnet Freight Rail, capable of running either on 3 kV electricity off the catenary or on diesel alone....
is a 3kV DC electro-diesel locomotive designed by Consortium under the leadership of Siemens
Siemens
Siemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...
and built by Union Carriage and Wagon (UCW) in Nigel, Gauteng
Gauteng
Gauteng is one of the nine provinces of South Africa. It was formed from part of the old Transvaal Province after South Africa's first all-race elections on 27 April 1994...
, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
. Between November 1992 and 1993 fifty of these locomotives were placed in service by Spoornet, formerly the South African Railways (SAR) and later renamed Transnet Freight Rail (TFR). The diesel engine enables the locomotive to shunt on unelectrified sidings.
Hybrid locomotive

Switcher
A switcher or shunter is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been...
.
See also
- BiodieselBiodieselBiodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl esters. Biodiesel is typically made by chemically reacting lipids with an alcohol....
- Global warmingGlobal warmingGlobal warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
- Three power locomotive
- Hitachi Super Express, a future train in the United Kingdom.