![OPE1A [ru; uk] industrial electro-diesel locomotive for quarry railways with primary electric locomotive and two diesel B-units OPE1A-044.jpg](http://upload.wikimedia.org/wikipedia/commons/thumb/d/d3/%D0%9E%D0%9F%D0%AD1%D0%90-044.jpg/220px-%D0%9E%D0%9F%D0%AD1%D0%90-044.jpg)
An electro-diesel locomotive (also referred to as a dual-mode or bi-mode locomotive) is a type of locomotive that can be 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.
Electro-diesel locomotives are used to provide continuous journeys along routes that are only partly electrified without a change of locomotive, avoid extensive running of diesel under overhead electrical wires and giving a solution 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.
Note that, as well as the electric multiple unit (EMU) and diesel multiple unit (DMU), where no discrete locomotive is present, an electro-diesel (bi-mode) multiple unit train is called electro-diesel multiple unit (EDMU) or bi-mode multiple unit (BMU).
This is effectively an electric locomotive with a relatively small auxiliary diesel prime mover intended only for low-speed or short-distance 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 that used tramways at the ports of Southampton and Weymouth. For economy, the diesel engine and its generator are considerably smaller than the electric capacity. The Southern types were of 1,600 horsepower (1,200 kW) or 'Type 3' rating as electrics, but only 600 horsepower (450 kW) as diesels. [1] Later classes had as much as 2,500 horsepower (1,900 kW) on electric power, but still the same diesel engines. Despite this large difference, their comparable tractive efforts were much closer (around three-quarters as diesels) and so they could start and work equally heavy trains as diesels, but not to the same speeds.
From 2010, in continental Europe, the name "Last mile diesel" was getting popular. These are electric locomotives with a small diesel engine of truck type, used in low speed, low gear, for operation at small flat freight yards, eliminating the need for a shunter locomotive.
This is effectively a diesel locomotive 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, GE Genesis P32AC-DM, EMD DM30AC). The primary function for these models is to provide a "one-seat ride" (a rail trip that does not require a transfer to a different train) between the electrified and non-electrified sections of a rail system or to allow trains to run through tunnels or other segments of track where diesel locomotives are generally prohibited due to their production of exhaust; such locomotives are used for certain trains servicing the New York City terminals of Grand Central Terminal and Penn Station, as the various rail tunnels into Manhattan have exhaust restrictions. Once out of the tunnels, the engines are started and operation is as a normal diesel locomotive.
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. British Rail Class 88, Bombardier ALP-45DP). 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.
ETG, an experimental electro-diesel shunter converted at Tbilisi locomotive depot in 1967 from AMG5 diesel-hydraulic shunting locomotive (manufactured by Gratz, Austria) by replacing its diesel prime mover with less powerful diesel engine and two electric motors from VL22m locomotive. The locomotive operated for several years and was withdrawn in the 1970s. [2]
In Russia, a number of electro-diesels were built which had both pantographs and diesel prime movers. These included:
An experimental electro-diesel locomotive, DEL120, was built by London Underground in 1940 but was not a success. Two types have been built whose electricity source was a 750 V DC third rail.
Electro-diesel locomotives whose electricity source is 25 kV 50 Hz AC overhead line include:
Several, primarily diesel locomotive types and a multiple-unit have been built to operate off a 750 V DC third rail into the New York City terminals of Grand Central Terminal and Penn Station (with the third rail system being rarely used on open-air tracks).
The following are in service:
The following were retired from New York City service:
The Indian Railways WDAP-5 is a class of Electro-diesel locomotive that was developed in 2019 by Banaras Locomotive Works (BLW), Varanasi for Indian Railways. The model name stands for broad gauge (W), Diesel (D), AC Current (A), Passenger (P) and 5000 Horsepower(5). The locomotive can deliver 5000HP in electric mode and 4500HP in diesel mode. Since 2016, Indian Railways has pushed for greater electrification of the railway network. [37] In this interest, the government approved plans for 100% electrification in 2019. [38] So far Indian Railways has electrified 39,866 RKMs which accounts for about 63% of the total route kilometres. [39] Using electric locomotives allows the railways to save time by giving a faster acceleration and also saves fuel costs. However, these advantages are offset under certain circumstances where the route of the train is partly electrified. In such cases, trains used to run with a diesel locomotive in non-electrified sections and would be switched with an electric locomotive as soon as they enter an electrified section. Instead of the benefits of electrification, Railways observed a loss of punctuality in such trains due to valuable time being lost to switch between diesel and electric locomotives. To counter this, in August 2019, Railways issued a circular, asking all zones to haul trains with a diesel locomotive if their route was not completely electrified. [40] This meant that electrification of railway lines, unless completed end-to-end, did not provide any advantage. This problem had been identified by the Railways, way back in 2016, which is when RDSO was requested to study the feasibility of dual-mode locomotives as a stop-gap until 100% electrification was achieved. [41]
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 from an external supply. An example is the Green Goat switcher GG20B by Railpower Technologies, a subsidiary of R.J. Corman Railroad Group since 2009. [42]
A locomotive or engine is a rail transport vehicle that provides the motive power for a train. If a locomotive is capable of carrying a payload, it is usually rather referred to as a multiple unit, motor coach, railcar or power car; the use of these self-propelled vehicles is increasingly common for passenger trains, but rare for freight trains.
A switcher locomotive, shunter locomotive, or shifter locomotive is a locomotive used for maneuvering railway vehicles over short distances. Switchers do not usually move trains over long distances, instead they typically assemble trains in order for another locomotive to take over. Switchers often operate in a railyard or make short transfer runs. They may serve as the primary motive power on short branch lines or switching and terminal railroads.
An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or on-board energy storage such as a battery or a supercapacitor. Locomotives with on-board fuelled prime movers, such as diesel engines or gas turbines, are classed as diesel–electric or gas turbine–electric and not as electric locomotives, because the electric generator/motor combination serves only as a power transmission system.
Railway electrification is the use of electric power for the propulsion of rail transport. Electric railways use either electric locomotives, electric multiple units or both. Electricity is typically generated in large and relatively efficient generating stations, transmitted to the railway network and distributed to the trains. Some electric railways have their own dedicated generating stations and transmission lines, but most purchase power from an electric utility. The railway usually provides its own distribution lines, switches, and transformers.
The British Rail Class 73 is a British electro-diesel locomotive. This type is unusual in that it can operate on the Southern Region's 650/750V DC third rail power supply, or an onboard diesel engine to allow it to be used on non-electrified routes. This makes it very versatile, although the diesel engine produces less power than is available from the third-rail power supply, so the locomotives are rarely used outside of the former Southern Region of British Rail. It is one of the first bi-mode locomotives ever built. Following the withdrawal and scrapping of the more powerful Class 74 bi-mode locomotives in 1977, the Class 73 was unique on the British railway network until the introduction of the Class 88 bi-mode locomotives in 2017. Ten locomotives have been scrapped.
In rail transport, head-end power (HEP), also known as electric train supply (ETS), is the electrical power distribution system on a passenger train. The power source, usually a locomotive at the front or 'head' of a train, provides the electricity used for heating, lighting, electrical and other 'hotel' needs. The maritime equivalent is hotel electric power. A successful attempt by the London, Brighton and South Coast Railway in October 1881 to light the passenger cars on the London to Brighton route heralded the beginning of using electricity to light trains in the world.
Alstom Traxx is a modular product platform of mainline diesel-electric and electric locomotives. It was produced originally by Bombardier Transportation and later Alstom, and was built in both freight and passenger variants. The first version was a dual-voltage AC locomotive built for German railways from the year 2000. Later types included DC versions, as well as quadruple-voltage machines, able to operate on most European electrification schemes: 1.5/3.0 kV DC and 15/25 kV AC. The family was expanded in 2006 to include diesel-powered versions. Elements common to all variants include steel bodyshells, two bogies with two powered axles each, three-phase asynchronous induction motors, cooling exhausts on the roof edges, and wheel disc brakes.
Railroad electrification in the United States began at the turn of the 20th century and comprised many different systems in many different geographical areas, few of which were connected. Despite this situation, these systems shared a small number of common reasons for electrification.
Withdrawn British Rail stock is British railway coaches, wagons and locomotives that have been removed from service.
Railway electric traction describes the various types of locomotive and multiple units that are used on electrification systems around the world.
The Class 13 are a type of mixed use 200 km/h (124 mph) multivoltage electric locomotive of type Traxis designed by Alstom in the late 1990s for the Belgian and Luxembourgish railways.
The British Rail Class 88 is a type of mainline mixed traffic electro-diesel locomotive manufactured by Vossloh España/Stadler Rail Valencia for Direct Rail Services (DRS) in the United Kingdom. The locomotive is part of the Stadler Euro Dual family. It is the first dual-mode locomotive in the UK to use the 25 kV AC electrification.
The Bombardier ALP-45DP is a type of single cab dual-mode locomotive operated by New Jersey Transit and Exo. The locomotive was designed and originally built by Bombardier until 2021, and by Alstom since 2021.
A multi-system locomotive, also known as a multi-system electric locomotive, multi-system electric multiple unit, or multi-system train, is an electric locomotive which can operate using more than one railway electrification system. Multi-system trains provide continuous journeys over routes which are electrified using more than one system.
The Transnet Freight Rail Class 20E of 2013 is a South African electric locomotive.
The Stadler EuroDual is a series of dual power, electro-diesel locomotive by Stadler Rail Valencia. Unlike traditional dual mode locomotives, fitted with relatively low-powered diesel engines for 'last mile' movements only, vehicles are typically furnished with power units more comparable to that of mainline diesel locomotives.
The Transnet Freight Rail Class 22E of 2015 is a South African electric locomotive.
An electro-diesel multiple unit (EDMU) or bi-mode multiple unit (BMU) is a form of a multiple unit train that can be powered either by electric power picked up from the overhead lines or third rail or by using an onboard diesel engine, driving an electric generator, which produces alternating current (AC) or direct current (DC) electric power.
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.
The British Rail Class 99 is a planned class of dual-mode electro-diesel Co-Co locomotives that will haul freight trains on both electrified and non-electrified lines. It will be based on the Stadler Euro Dual platform.