Railway electrification in Great Britain

Contents 1 History 2 Proposed developments 3 Existing systems – overhead line (OHL) 3.1 25 kV, 50 Hz AC overhead 3.2 1,500 V DC, overhead 3.3 750 V DC, overhead 3.4 600 V DC, overhead 3.5 120 V DC, overhead 4 Existing systems - third and fourth rails 4.1 650 V - 750 V DC, third rail 4.2 630 V DC, fourth rail 4.3 750 V DC, third rail (bottom contact) 4.4 600 V DC, third rail 4.5 250 V DC, third rail 4.6 110 V DC, third rail 4.7 100 V DC, four rail 5 Obsolete systems 5.1 6,600 V, 25 Hz AC, overhead 5.2 6,250 V 50 Hz AC, overhead 5.3 3,500 V DC, overhead 5.4 1,500 V DC, overhead 5.5 1,200 V DC, third rail (side-contact) 5.6 650 V DC, overhead 5.7 600 V DC, third rail 5.8 550 V DC, overhead 5.9 525 V DC, third rail 5.10 500 V DC, overhead 5.11 500 V DC, third rail 6 Facts and figures 7 See also 8 References 9 Further reading 9.1 525 V DC, third rail 9.2 630 V DC, fourth rail 9.3 650 V DC, third rail 9.4 750 V DC, third rail 9.5 1,500 V DC, overhead 9.6 6.6 kV 25 Hz AC, overhead 9.7 25 kV 50 Hz AC, overhead 10 External links

Railway electrification in Great Britain began during the late 19th century. A range of voltages have been used in the intervening period, employing both overhead lines and third rails; however the most common standard for mainline services is now 25 kV AC using overhead lines and the 750 V DC third-rail system used in southeast England. 40 percent—3,062 miles (4,928 km)—of the British rail network was electrified, and 60 percent of all rail journeys were by electric traction (both by locomotives and multiple units). 66 percent of the electrified network uses the 25 kV AC overhead system, and 36 percent uses the 660/750 V DC third-rail system.^{[when?][citation needed]} Subways, light rail and tram systems employ a variety of other systems.

History

Railway electrification had advantages over the then-predominant steam traction—particularly with respect to rapid acceleration, which was ideal for urban (metro) and suburban (commuter) services—and higher power (ideal for heavy freight trains in mountainous or hilly sections). Many systems emerged in the first two decades of the 20th century. In 1921 a government committee chose 1,500 V DC overhead to be the national standard,^[1] but little implementation followed and many different systems co-existed.

After World War II and the nationalisation of the railways in 1948, British Railways expanded electrification of both the 1,500 V DC overhead and Southern Region third rail systems. However in 1956, British Railways adopted 25 kV AC overhead as standard for all future projects outside logical extensions of existing third-rail systems.^[2]

The 25 kV AC network has continued to expand slowly, although large areas of the country outside London are still non-electrified. In 2007 the British government's preferred option was to use diesel trains and run them on biodiesel. In its 2007 white paper Delivering a Sustainable Railway,^[3] the government ruled out large-scale railway electrification for the following five years.

In May 2009 Network Rail launched a consultation on large-scale electrification (to potentially include the Great Western Main Line and Midland Main Line) and smaller "in-fill" schemes. Key benefits cited in the consultation were that electric trains are faster, more reliable and cause less track wear than diesel trains.^[4] Since then, electrification of the Great Western Main Line has been approved; trains are planned to run to Bristol from 2016 and Cardiff from 2017.^[5]

In Scotland, where transport is a matter devolved to the Scottish Government, Transport Scotland is extending electrification (for example, on the Airdrie-Bathgate Rail Link). This is part of a larger plan which foresees many major routes in central Scotland electrified, including the main Edinburgh-to-Glasgow Queen St route.

Proposed developments

In June 2011, Peter Dearman of Network Rail suggested that the third-rail network will need to be converted into overhead power lines in the future. He stated, "Although the top speed is 100mph, the trains cannot go over 80mph well and 25% of power is lost from heat". Agreeing that conversion would be expensive, he also said that the third-rail network is at its limit of its power capability of power (especially as trains become more advanced in technology).^[6]

Existing systems – overhead line (OHL)

25 kV, 50 Hz AC overhead

London, Tilbury and Southend (LTS)

The majority of this line was originally electrified at 6,250 V. It was converted to 25 kV in the early 1960s.

Great Eastern Main Line (GEML)

• Converted from 1,500 V DC (see 1,500 V DC section "Shenfield Metro")
• Converted from 6,250 V/1,500 V DC
• Romford to Upminster Line
• Shenfield to Southend Line
• Crouch Valley Line
• Braintree Branch Line
• Colchester to Clacton Line
• Mayflower Line

West Anglia / Fen Line

This covers the lines from London Liverpool Street (Bethnal Green Jn) to Chingford, Enfield Town, Hertford East and Cambridge. The line was first electrified during the 1960s, when the lines to Chingford, Enfield Town and Cheshunt were electrified at 6,250 V. The line from Cheshunt to Bishop's Stortford and Hertford East was electrified at 25 kV. The Lea Valley line between Coppermill Junction and Cheshunt was electrified at 25 kV in 1969. All the 6,250 V areas were converted to 25 kV in 1983. In 1987, electrification was extended from Bishop's Stortford to Cambridge using 25 kV. In 1990 the line to Stansted Airport opened, and in 1992 electrification was further extended from Cambridge to King's Lynn along the Fen Line.

East Coast Main Line (ECML)

• Electrified in two parts: the first between 1975 and 1978, and the second between 1984 and 1991
• The line between London (Kings Cross) and Royston was electrified between 1976 and 1978 as part of the Great Northern Suburban Electrification Project. This included the Hertford Loop Line.
• In 1984, authority was given to electrify to Edinburgh and Leeds. The section between Hitchin and Peterborough was completed in 1987, and Doncaster and York were reached in 1989. By 1990 electrification had reached Newcastle, and in 1991 the final section to Edinburgh was completed.
• In order to keep construction teams working, two additional schemes were authorised which extended electrification to Carstairs and North Berwick (North Berwick Line).
• At the peak of the electrification project during the late 1980s, it was claimed to be the "longest construction site in the world" at over 250 miles (400 km).

Midland Main Line (MML)

• Electrified between London (St Pancras) and Bedford in 1983. The section from Dock Junction to Moorgate was also electrified.

West Coast Main Line (WCML)

• Electrified from the late 1950s to the mid-1960s under the BR 1955 Modernisation Plan as far as Crewe (and branches), it was extended to Glasgow in 1974.
• Northampton: See Northampton Loop Line.
• Birmingham (New Street): See Rugby-Birmingham-Stafford Line.
• Liverpool (Lime Street)
• Manchester (Piccadilly): See Stafford to Manchester Line and Crewe to Manchester Line.
• Glasgow (Central): in 1974, from Weaver Junction
• The "Abbey Flyer" (St Albans Branch Line) was electrified 1987-88 by Network SouthEast.
• Edinburgh (Waverley) in 1989 (from Carstairs Junction in conjunction with ECML electrification)
• In 2003, the Crewe to Kidsgrove section of the Crewe to Derby Line was electrified as a diversionary route for the WCML.
• Since 1999 the line has been modernised and the overhead line equipment has undergone a programme of refurbishment and renewal as part of a plan to increase train speeds from 110 mph to 125 mph.

Edinburgh

• In 1991 the ECML to Edinburgh was electrified. A few local routes were electrified, but most local services were not.
• Edinburgh Crossrail: Edinburgh Waverley to Newcraighall only. Currently the service is by DMUs, pending reopening of part of the Waverley Line.
• North Berwick Line: Edinburgh Waverley to North Berwick, with some extensions to Edinburgh Haymarket
• Glasgow to Edinburgh via Carstairs Line: some North Berwick Line trains continue to Glasgow Central. Intercity trains from the ECML continue to Glasgow Central.

Central Scotland

The route from Edinburgh to Glasgow via Bathgate has been reinstated between Bathgate and Airdrie and electrified throughout. It opened on 11 December 2010. Approval has also been given by the Scottish Parliament for electrification of the main inter-city route between Edinburgh and Glasgow Queen Street (high-level station, not currently electrified) via Falkirk. This project will also encompass some infill electrification in the Glasgow area and Greenhill Junction to Stirling, Dunblane and (recently re-opened) Alloa (which mainly carry commuter services); however, it will enable electric haulage from London via the ECML as far as Stirling or Dunblane.

Glasgow Suburban

Suburban electrification was begun during the 1960s in the wake of the BR 1955 Modernisation Plan. Electrification was piecemeal during the preceding year and is still incomplete, with several suburban, rural and intercity lines still unelectrified.

The Glasgow Suburban railway network can be divided into three main areas:

• North Clyde: Also known as the "Glasgow North Electric Suburban Line", this was one of the first lines in Glasgow to be electrified in 1960 (Helensburgh Central, Balloch and Milngavie to Glasgow Queen Street (Low Level) and to Springburn and Airdrie).
• South Clyde: The Cathcart Circle Line (Glasgow Central to Newton and Neilston) was electrified on 22 May 1962.^[7] The Inverclyde Line (Glasgow Central to Gourock and Wemyss Bay) was electrified in 1967.^[7] The Ayrshire Coast Line (Glasgow Central to Ayr, Largs and Ardrossan Harbour) was electrified in 1986–1987.^[8] The Paisley Canal Line was electrified only as far as Corkerhill (from Glasgow Central).
• West Coast Main Line: The Argyle Lineruns between Dalmuir and Milngavie via Glasgow Central (Low Level) to Hamilton Circle, Larkhall, Lanark and Carstairs (via a variety of lines via Hamilton, Motherwell or Holytown). There is also peak service to Coatbridge Central.

On the Glasgow to Edinburgh via Carstairs Line, some North Berwick Line trains continue to Glasgow Central. A single daily Eastcoast intercity train (from the ECML) continues to and from Glasgow Central. On the Motherwell to Cumbernauld Line, the Motherwell to Coatbridge section is electrified, but the Coatbridge to Cumbernauld section is not. On the Shotts Line the central section (Holytown Junction to Kirknewton) is not electrified, but both ends are (since they are shared with the WCML, Argyle Line and ECML). The Whifflet Line (the line between Whifflet and Rutherglen via Carmyle) is not electrified, although there are plans to do so by 2014.^[9] Whifflet station is electrified, as part of the Motherwell to Cumbernauld line.

Leeds area

The main line to Leeds from London (via Wakefield Westgate) was electrified in 1989. In 1994, a project to electrify some of the local lines around Leeds was given authority to proceed. The project was called the "Leeds North West Electrification" and covered lines to Bradford (Forster Square), Skipton (Airedale Line) and Ilkley (Wharfedale Line).

Manchester area

• Manchester to Glossop / Hadfield (converted from the truncated 1500 V DC Manchester-Sheffield-Wath electric railway)
• Manchester, South Junction and Altrincham Railway (part was converted to Manchester Metrolink)
• Styal Line (primarily operated by diesel multiple units)
• Stafford to Manchester Line: A branch of the WCML, electrified in the wake of the BR 1955 Modernisation Plan
• Crewe to Manchester Line: Also a branch of the WCML, electrified in the wake of the 1955 Modernisation Plan
• Liverpool to Manchester Line: To be electrified, as part of plans announced by the British government in July 2009^[10]

West Midlands

• A few lines out of New Street, mainly related to the West Coast Main Line
• Trent Valley Line: WCML, 1964
• Rugby-Birmingham-Stafford Line: WCML, 1966
• Cross-City Line: 1993
• Walsall Line: Electrified from New Street to Walsall

Great Western Main Line (GWML)

Electrified in 1994 between London Paddington and Heathrow Airport, the GWML is a joint venture between British Rail and the British Airports Authority. As part of the works for Crossrail, the electrified section will be extended as far as Maidenhead. The line from Maidenhead to Bristol and Cardiff (and lines to Newbury and Oxford) are also to be electrified as part of the GWML upgrade.^[11]

1,500 V DC, overhead

• Tyne and Wear Metro: The Tyne and Wear Metro, which opened in 1980, is now the only system in the UK to use 1500 V DC overhead lines. Although it is often described as "light rail" it is closer to a heavy metro in design, using only segregated track. Much of its route follows that of the previous Tyneside Electrics, which had been converted to diesel by 1967. Since 2002, the Metro has shared mainline track on the Durham Coast Line to Sunderland, although the overhead lines are not used by any trains other than the Metro; this presents a potential problem for mainline services, should routes into Sunderland or Newcastle upon Tyne which use this section be electrified at 25 kV AC.

750 V DC, overhead

• Manchester Metrolink
• Sheffield Supertram
• Croydon Tramlink
• Nottingham express transit
• Midland Metro

600 V DC, overhead

• Blackpool Tramway: Originally 550 V, in 2011 it was upgraded to 600 V to operate more modern rolling stock.

120 V DC, overhead

• Seaton Tramway

Existing systems - third and fourth rails

650 V - 750 V DC, third rail

Southern Electric

The LSWR third-rail system at 660 V DC began before World War I from Waterloo to several suburban destinations. The Southern Railway was one of the companies formed in the 1923 grouping; it adopted the LSWR system, and by 1929 the LBSCR suburban overhead network was replaced by third rail. The South Eastern Main Line was electrified at 600 V, but later upgraded to 750 V DC. The third rail extended throughout most South London lines under Southern control (LBSCR and SECR), and then out of all its London termini. Throughout the 1930s there was much main line electrification, including the Brighton mainline (including East, West Coastways and related routes in 1932-1933), the Portsmouth Direct Line (4 July 1937) and the lines to Maidstone and Gillingham (1939).

After World War II, electrification was soon resumed in the newly-nationalised British Rail's southern region. The BR 1955 Modernisation Plan included the two-stage "Kent Coast Electrification". The Chatham mainline was completed, followed by the SER mainline and related lines. At this time, the voltage used was changed from 660 V to 750 V.^[12] Since then, all further electrification has used 750 V; however, the lines electrified before this time remain at 660 V. Attention then switched to the neglected LSWR region (now titled the South Western Division). The South Western Main Line (SWML) to Southampton and Bournemouth was electrified in 1967 and completed to Weymouth in 1988. The Island Line was electrified in 1967.^[13]

During sectorisation in the 1980s, Network SouthEast conducted extensive infill electrification. The Snow Hill tunnel was reopened, enabling Thameslink. The Hastings Line, Eastleigh to Fareham Line and the Oxted Line (East Grinstead branch) were also electrified. This left only a few generally-isolated, rural lines and freight branches unelectrified (the West of England Main Line, the North Downs Line, the Marshlink Line, and the Oxted Line Uckfield branch).

Merseyrail

This uses 750 V^[14][15] (see Suburban electrification of the London, Midland and Scottish Railway for its history).

London and North Western Railway

• Euston and Broad Street to Watford Junction and Croxley Green (Watford DC Line)
• Richmond – North Woolwich (North London Line)

See Suburban electrification of the London, Midland and Scottish Railway for its history.^[16] In 1970 the North London DC lines and the Class 501 EMUs used on these services were converted for third-rail operation, with the fourth rail generally being removed on sections of lines not used by LUL. Some fourth rail was retained in the Gunnersbury and Queens Park areas for emergency use by LUL. With the closure of Broad Street, the North London Line was joined with the former Broad Street to North Woolwich via Stratford line, to extend the NLL; this section was electrified with third rail and overhead line as far as Stratford and third rail alone to North Woolwich. Two branches of the Watford DC Line have been closed: to Rickmansworth in 1952 (to passengers, to goods in 1967) and to Croxley Green in 1996.

The Watford DC Line between Queens Park and Harrow & Wealdstone is used by London Overground trains designed for 750 V third rail and Bakerloo Line trains designed for 630 V third and fourth rail. As a compromise the nominal line voltage is 650 V, and the centre rail is bonded to the return running rail. There are no special provisions required at Queens Park where the two dissimilar systems meet—merely a gap longer than one coach of a Bakerloo Line train at the entry to (and exit from) the Bakerloo Line section, which operates with a nominal -210 V on the fourth rail and +420 V on the third rail. There is no bridging of these incompatible systems as trains pass from one to the other since, like all UK electric trains intended to run extensively in tunnels, there is no continuity of traction power circuits between vehicles of the train.

The North London Line between Richmond and Gunnersbury is used by London Overground trains designed for 750 V third rail and District Line trains designed for 630 V third and fourth rail. As a compromise the nominal line voltage is 660 V, and the centre rail is bonded to the return running rail. A similar arrangement applies on the District Line between Putney Bridge and Wimbledon, where the District Line runs over tracks owned by Network Rail. These tracks are used by South West Trains (normally only for stock movements).

Northern City Line

The Northern City Line connects the East Coast Main Line to Moorgate. It was isolated by the abandonment of the 1930s "New Works" programme (and the development of the Metropolitan Green Belt). Tube services were truncated at its northern end by the new Victoria Line in 1964 at Drayton Park. The remainder was handed over to BR in 1975 in conjunction with the suburban electrification of the East Coast Main Line. The line uses 25 kV AC overhead and third-rail DC electrification at 750 volts, with the switchover at the platform at Drayton Park.

630 V DC, fourth rail

London Underground

The London Underground is a large metro system operating across London, and beyond, commonly known as "the Tube". The 408-kilometre (254 mi)^[17] network is made up of 11 lines; electrification began during the 1890s. The network was largely unified between 1900–1910 and nationalised in 1933, becoming the railway component of London Transport (LT). A major expansion programme (the "New Works") was launched, by which LT took over several urban branches of mainline railways.

The London Underground network has historically been located in north London; its expansion into south London was limited by geology unfavourable to tunnelling and by the extensive above-ground railway network in the area, much of which was being electrified (see "Southern Electric"). The Underground uses a relatively-uncommon four rail system of electrification. Two standard gauge rails are the running rails; the outer third rail carries positive current at +420 V DC and the inner fourth rail is the negative return at –210 V DC, giving a supply voltage of 630 V DC. The chief advantage of the fourth-rail system is that, in tunnels with a metallic (usually cast-iron) lining, the return traction current does not leak into the lining causing electrolytic corrosion there or in the neighbouring utility mains). The two running rails are also available exclusively for signalling track circuits.

The surface sections of the lines use the fourth rail solely for operational consistency; the system shares track with Network Rail in several places. Some of these are non-electrified sections of the national railway network (e.g. Chiltern Railways out of Marylebone station), and diesel trains are used (by Network Rail). The suburban network of London North Western Railway (LNWR) was electrified in co-operation with London Underground, but during the 1970s British Rail introduced third-rail EMUs and the sections of the LNWR suburban network not used by the Underground had the fourth rail removed (see "London and North Western Railway", above).

750 V DC, third rail (bottom contact)

Docklands Light Railway

This system uses bottom-contact third rail. The third rail is composite, with an aluminium body and a steel contact surface. The advantage of this is a low-resistance, high-current-capacity rail with a durable steel surface for current collection. The rail may be surrounded by insulating material on the top and sides to reduce the risk of electrocution to railway staff and trespassers. The bottom-contact system is less prone to derangement by snow than the top-contact system.

600 V DC, third rail

• Glasgow Subway, electrified in 1935

250 V DC, third rail

• Hythe Pier Railway, electrified in 1922

110 V DC, third rail

• Volk's Electric Railway was originally electrified at 50 V DC. This was raised to 160 V in 1884, and then reduced to the present 110 V DC during the 1980s.

100 V DC, four rail

• Elevated "monorail" system at the National Motor Museum, Beaulieu. Although described as a monorail, the system actually uses rubber tyres which run on two metal tracks, one on either side of the central guide. Because it is rubber-tyred, it requires two current conductors and two collectors (hence the four-rail designation).

Obsolete systems

Great Britain has used a number of different electrification systems in the past. Many of these date from the early part of the 20th century, when traction electricity was in the experimental stage. This section describes each system, in order of decreasing voltage.

6,600 V, 25 Hz AC, overhead

• Lancaster to Heysham via Morecambe: Used for an early trial of electrification; operated between 13 April and 14 September 1908.
• LBSCR's 'Elevated Electric' London suburban lines: The first large-scale suburban electrification scheme; operational between 1 December 1909 and 1 April 1925, but replaced by September 1929.

6,250 V 50 Hz AC, overhead

During the initial electrification of parts of the network to 25 kV 50 Hz AC overhead, the initial solution to the limited clearance problems in suburban areas (due to numerous tunnels and bridges) in London and Glasgow was to use the lower voltage of 6,250 V. Later technological improvements in insulation allowed these areas to be converted to 25 kV. The last sections of 6,250 V were converted during the 1980s.

London, Tilbury and Southend (LTS)

Most of the line was electrified at 6,250 V during the early 1960s. Some sections were electrified using 25 kV from the outset. The sections electrified at 6,250 V were converted to 25 kV during the early 1980s.

Shenfield Metro

The line was originally electrified at 1,500 V DC overhead during the 1950s. During the early 1960s, the line was converted to 6,250 V AC overhead; during the early 1980s the line was again converted, this time to 25 kV.

Glasgow Suburban network

• The majority of the network was originally electrified at 6,250 V during the early 1960s. Some sections were electrified using 25 kV from the outset. The sections electrified at 6,250 V were converted to 25 kV during the early 1980s.
• North Clyde Line (central area, Springburn, Bridgeton and Milngavie branches and the Yoker loop)
• Cathcart Circle Line

3,500 V DC, overhead

Bury to Holcombe Brook

This was electrified by the Lancashire and Yorkshire Railway in 1913 as part of a trial system for export. The system was converted to third rail in 1918 (see above).^[18]

1,500 V DC, overhead

After World War I, the UK Government set up a committee to investigate the various systems of railway electrification; in 1921, it recommended that 1,500 V DC overhead should be the future national standard.^[1] Several schemes were implemented in its wake, but the Great Depression and World War II meant very little work was done. Technological advances after 1945 meant the 25 kV AC system was adopted instead for the West Coast Main line and Glasgow suburban electrification (as set out in the BR 1955 Modernisation Plan). However, at the same time large amounts of money had been (and were still being) spent converting several lines to 1,500 V DC.

Manchester, South Junction and Altrincham Railway

A joint LMS and LNER scheme, it opened on 11 May 1931. The success of this scheme influenced LNER's later electrification schemes. The line was converted to 25 kV AC in 1971, but the stretch between Altrincham and Trafford Bar (plus the stretch between Trafford Bar and the Cornbrook viaduct) were later incorporated into Manchester Metrolink and converted again (this time to 750 V DC).^[19]

Manchester – Sheffield – Wath

Known as the Woodhead Route, the LNER chose this hilly (and busy) mainline for its first mainline electrification, with work beginning in 1936.^[20] Due to the Depression and World War II, it was not completed until the 1950s. After completion, the government chose to standardise on 25 kV AC instead, leaving the Woodhead Route and the few other 1,500 V DC lines isolated and non-standard. In a subsequent rationalisation, BR closed much of this route east of Hadfield in 1981 in favour of the more southerly Hope Valley Line, which serves more local communities. The remaining section in Manchester was converted to 25 kV AC in December 1984. The passenger locomotives were sold and saw further service in the Netherlands.

Shenfield Metro

The LNER decided to electrify the Liverpool Street to Shenfield section of the Great Eastern Main Line (GEML), known as the Shenfield Metro. Civil engineering works began during the 1930s, but World War II intervened. Work was completed in 1949 and extended to Chelmsford and Southend Victoria in 1956, using Class 306 (AM6) EMUs.^[21] It was converted to the new standard of 25 kV AC (initially with some sections at 6,250 V) on 4–6 November 1960, in the wake of the BR 1955 Modernisation Plan which called for 25 kV AC to be the new standard. The rest of the GEML was subsequently electrified.

Shildon to Newport

This line ran from Shildon (County Durham) to Newport (near Middlesbrough). The route was initially over the 1825 Stockton-to-Darlington line, then via Simpasture Junction (the former Clarence railway) through Carlton, Carlton Junction to Carlton South Junction, Bowesfield West Junction to Bowesfield Junction, through Thornaby and ending at Erimus Yard (Newport East). In the wake of the electrification of Tyneside by the NER, this coal-carrying line was electrified between 1 July 1915 and 1 January 1916 as a planned precursor to electrifying NER's busy York to Newcastle main line (part of the ECML). The LNER removed this electrification system in 1935 (between 7 January and 8 July); the decline in the coal market made it economically unfeasible to undertake the significant renewals required to continue electric operation. The locomotives were stored for other electrified routes.^[22][23][24]

1,200 V DC, third rail (side-contact)

Manchester Victoria - Bury

In 1917, the line between Manchester Victoria and Bury was electrified using 1,200 V DC third rail (side contact). The line between Bury and Holcombe Brook which had been electrified using 3,500 V DC overhead in 1913 was converted to this system in 1918. It was abandoned in 1991, when the line was converted to a 750 V DC system and became part of the Manchester Metrolink.^[25][26]

650 V DC, overhead

• Swansea and Mumbles Railway

600 V DC, third rail

Tyneside Electric

This was electrified in 1904, in response to extensive competition from new electric trams. The concept was a success for the North Eastern Railway (NER), a noted pioneer in electrification, as passenger numbers returned to pre-tram levels.^[27] As the stock reached life expectancy in 1937, the network was remodelled by London and North Eastern Railway (LNER) to reflect the changing industrial and residential makeup of the area.^[28] Electrified at the same time was the dockside branch, where a pair of Class ES1 (formerly NER No.1 and 2) locomotives were introduced in 1905. These British Thomson-Houston locomotives operated from both the third rail and overhead line. British Rail brought in third-rail stock (12 2EPBs) from the Southern Region in 1955. British Rail removed the electrification between 1963 and 1967, citing the changing industrial and population makeup of the area which reduced the need for electric traction. Much of the Tyneside network was later re-electrified (using 1500 V DC overhead) as the Tyne and Wear Metro.

550 V DC, overhead

• Blackpool Tramway

525 V DC, third rail

Liverpool Overhead Railway

The Liverpool Overhead Railway was one of the earliest electric railways in Great Britain. The first section, between Alexandra Dock and Herculaneum Dock, was opened in 1893. The line connected with Lancashire and Yorkshire Railway's North Mersey Branch. It was never nationalised, and closed on 30 December 1956 due to extensive corrosion throughout its iron infrastructure (which was deemed uneconomical to replace).

500 V DC, overhead

• Grimsby and Immingham Railway

500 V DC, third rail

City and South London Railway

The City and South London Railway electrification was unusual (compared with later schemes) in that it used a three-wire DC system. This meant that although the offset centre third rail was electrified at +500 volts in the northbound tunnel, it was electrified at -500 volts in the southbound tunnel. The motors on the locomotives and the incandescent electric lamps in the carriages worked, regardless of the polarity of the supply. The three-wire system was adopted because the initial system was fed directly from the dynamos in the surface power plant at the Stockwell end of the line. It was important to minimise the voltage drop as much as possible, bearing in mind the rather steep gradient on the approach to King William Street station.

Facts and figures

In 2006, 40 percent (3,062 miles (4,928 km)) of the British rail network was electrified, and 60 percent of all rail journeys were by electric traction (both by locomotives and multiple units).^[29] According to Network Rail, 66 percent of the electrified network uses the 25 kV AC overhead system, and 36 percent uses the 660/750 V DC third-rail system.^[29]

See also

• Suburban electrification of the London, Midland and Scottish Railway
• Manchester-Sheffield-Wath electric railway
• Volk's Electric Railway

References

Further reading

525 V DC, third rail

• Box, Charles E. (1959). Liverpool Overhead Railway. Railway World Ltd.. 
• Gahan, John W. (1992). Seventeen stations to Dingle - The Liverpool Overhead Railway remembered. Countyvise and Avon-Anglia. ISBN 0-907768-20-2. 
• Bolger, Paul (1992). The Docker's Umbrella - A History of Liverpool Overhead Railway. The Bluecoat Press. ISBN 1-872568-05-X. 
• Jarvis, Adrian (1996). Portrait of the Liverpool Overhead Railway. Ian Allan. ISBN 0-7110-2468-5. 

630 V DC, fourth rail

• Glover, John (2003). London's Underground (10th Edition). Ian Allan. ISBN 0-7110-2935-0. 

650 V DC, third rail

• Maund, T.B. (2001). Merseyrail Electrics - The Inside Story. NBC Books. ISBN [[Special:BookSources/0-9531896-1-3|0-9531896-1-3]]. 

750 V DC, third rail

• Moody, G.T. (1979). Southern Electric 1909-1979. Ian Allan. ISBN 0-7110-0924-4. 
• Glover, John (2001). Southern Electric. Ian Allan. ISBN 0-7110-2807-9. 

1,500 V DC, overhead

• Appleby, K.C. (1990). Shildon - Newport in Retrospect. Lincoln: Railway Correspondence and Travel Society. ISBN 0-901115-67-3. 
• Dixon, Frank (1994). The Manchester South Junction & Altrincham Railway. The Oakwood Press. ISBN 0-85361-454-7. 

6.6 kV 25 Hz AC, overhead

• Goslin, Geoff (2002). London's Elevated Electric Railway - The LBSCR Suburban Overhead Electrification 1909-1929. Connor & Butler Ltd. ISBN [[Special:BookSources/0-947669-35-X|0-947669-35-X]]. 

25 kV 50 Hz AC, overhead

• Nock, O.S. (1966). Britain's New Railway. Ian Allan. 
• Nock, O.S. (1974). Electric Euston to Glasgow. Ian Allan. ISBN 0-7110-0530-3. 
• Boocock, Colin (1991). East Coast Electrification. Ian Allan. ISBN 0-7110-1979-7. 
• Semmens, Peter (1991). Electrifying the East Coast Route. Patrick Stephens Ltd.. ISBN 0-85059-929-6. 
• Glover, John (2003). Eastern Electric. Ian Allan. ISBN 0-7110-2934-2. 

External links

• Citytransport.info's Electrification advocacy page
• Kent Rail
• Lancashire & Yorkshire Railway Society Archived 12 July 2006 at the Wayback Machine
• Southern E-mail Group
• Southern Electric Group
• Suburban Electric Railway Association

v t e Railway electrification Topics List of systems Railway electrification system Railway electric traction Traction substation Traction power network Pantograph Power car Electric locomotive Electric multiple unit Electro-diesel locomotive Multi-system Overhead lines Third rail Trolley pole Conduit current collection Ground level power supply Stud contact system By country Australia Great Britain France India Iran Japan Malaysia Norway timeline Sweden Turkey United States