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Metra Electric District

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Great Central Station , also known as Great Central Depot , was an intercity train station in Chicago , Illinois , owned by the Illinois Central Railroad (IC). It opened in 1856 and for a time was the largest building in downtown Chicago. Its passenger depot building was located on Water Street. The IC had its headquarters in offices above the depot, while beyond the depot was the large rail house where eight track lines ran. It was damaged in the Great Chicago Fire of 1871 but remained in operation.

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92-497: The Metra Electric District is an electrified commuter rail line owned and operated by Metra which connects Millennium Station (formerly Randolph Street Station), in downtown Chicago , with the city's southern suburbs . As of 2018, it is the fifth busiest of Metra's 11 lines, after the BNSF , UP-NW , UP-N , and UP-W Lines with nearly 7.7 million annual riders. While Metra does not explicitly refer to any of its lines by color,

184-630: A "South Lakefront Study" that is anticipated to yield either one or two new transit projects that are eligible for Federal transit funding. An extension to Peotone, Illinois or the Proposed Chicago south suburban airport with a stop in Monee has been considered since the SouthWest Service was extended to Manhattan. On May 24, 2017, Metra announced new schedule proposals for the line. The new schedule will provide rapid service for

276-402: A (nearly) continuous conductor running along the track that usually takes one of two forms: an overhead line , suspended from poles or towers along the track or from structure or tunnel ceilings, or a third rail mounted at track level and contacted by a sliding " pickup shoe ". Both overhead wire and third-rail systems usually use the running rails as the return conductor, but some systems use

368-573: A higher total efficiency. Electricity for electric rail systems can also come from renewable energy , nuclear power , or other low-carbon sources, which do not emit pollution or emissions. Electric locomotives may easily be constructed with greater power output than most diesel locomotives. For passenger operation it is possible to provide enough power with diesel engines (see e.g. ' ICE TD ') but, at higher speeds, this proves costly and impractical. Therefore, almost all high speed trains are electric. The high power of electric locomotives also gives them

460-467: A historical concern for double-stack rail transport regarding clearances with overhead lines but it is no longer universally true as of 2022 , with both Indian Railways and China Railway regularly operating electric double-stack cargo trains under overhead lines. Railway electrification has constantly increased in the past decades, and as of 2022, electrified tracks account for nearly one-third of total tracks globally. Railway electrification

552-699: A new station at the south end of the coach storage yard, in 1946. The main line had six tracks between Roosevelt Road (Central Station) and 53rd Street (reduced to four in 1962), four to 111th Street, then two. The South Chicago branch is double tracked, and the Blue Island branch has a single track with a passing siding at West Pullman . The Illinois Central Gulf commuter rail crash , the worst rail accident in Chicago history, occurred on October 30, 1972. A commuter train made up of new lightweight bi-level Highliner cars, inbound to Randolph Street Station during

644-537: A number of European countries, India, Saudi Arabia, eastern Japan, countries that used to be part of the Soviet Union, on high-speed lines in much of Western Europe (including countries that still run conventional railways under DC but not in countries using 16.7   Hz, see above). Most systems like this operate at 25   kV, although 12.5   kV sections exist in the United States, and 20   kV

736-457: A power grid that is delivered to a locomotive, and within the locomotive, transformed and rectified to a lower DC voltage in preparation for use by traction motors. These motors may either be DC motors which directly use the DC or they may be three-phase AC motors which require further conversion of the DC to variable frequency three-phase AC (using power electronics). Thus both systems are faced with

828-405: A rapid transit line, by running trains more frequently (every ten minutes between 6am and midnight) with reduced-fare transfers to CTA buses and trains. Unlike the current service, which bypasses many stations to reach suburban stations more quickly, it would make all stops within the city. It would run from Millennium Station to South Chicago (93rd Street) at an estimated cost at $ 160 million. Since

920-498: A relative lack of flexibility (since electric trains need third rails or overhead wires), and a vulnerability to power interruptions. Electro-diesel locomotives and electro-diesel multiple units mitigate these problems somewhat as they are capable of running on diesel power during an outage or on non-electrified routes. Different regions may use different supply voltages and frequencies, complicating through service and requiring greater complexity of locomotive power. There used to be

1012-481: A separate fourth rail for this purpose. In comparison to the principal alternative, the diesel engine , electric railways offer substantially better energy efficiency , lower emissions , and lower operating costs. Electric locomotives are also usually quieter, more powerful, and more responsive and reliable than diesel. They have no local emissions, an important advantage in tunnels and urban areas. Some electric traction systems provide regenerative braking that turns

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1104-418: A third rail. The key advantage of the four-rail system is that neither running rail carries any current. This scheme was introduced because of the problems of return currents, intended to be carried by the earthed (grounded) running rail, flowing through the iron tunnel linings instead. This can cause electrolytic damage and even arcing if the tunnel segments are not electrically bonded together. The problem

1196-536: A wider roof. On its completion the station was the largest building in Chicago. In 1871, the Great Chicago Fire destroyed the train shed, which was never rebuilt. A subsequent fire in 1874 damaged the head house. Great Central Station officially opened on June 1, 1856. It was the Illinois Central's first permanent station in Chicago and cost US$ 250,000 . The Great Central originally served

1288-411: Is derived by using resistors which ensures that stray earth currents are kept to manageable levels. Power-only rails can be mounted on strongly insulating ceramic chairs to minimise current leak, but this is not possible for running rails, which have to be seated on stronger metal chairs to carry the weight of trains. However, elastomeric rubber pads placed between the rails and chairs can now solve part of

1380-451: Is effected by one contact shoe each that slide on top of each one of the running rails . This and all other rubber-tyred metros that have a 1,435 mm ( 4 ft  8 + 1 ⁄ 2  in ) standard gauge track between the roll ways operate in the same manner. Railways and electrical utilities use AC as opposed to DC for the same reason: to use transformers , which require AC, to produce higher voltages. The higher

1472-526: Is electrified, companies often find that they need to continue use of diesel trains even if sections are electrified. The increasing demand for container traffic, which is more efficient when utilizing the double-stack car , also has network effect issues with existing electrifications due to insufficient clearance of overhead electrical lines for these trains, but electrification can be built or modified to have sufficient clearance, at additional cost. A problem specifically related to electrified lines are gaps in

1564-486: Is limited and losses are significantly higher. However, the higher voltages used in many AC electrification systems reduce transmission losses over longer distances, allowing for fewer substations or more powerful locomotives to be used. Also, the energy used to blow air to cool transformers, power electronics (including rectifiers), and other conversion hardware must be accounted for. Standard AC electrification systems use much higher voltages than standard DC systems. One of

1656-778: Is no longer exactly one-third of the grid frequency. This solved overheating problems with the rotary converters used to generate some of this power from the grid supply. In the US , the New York, New Haven, and Hartford Railroad , the Pennsylvania Railroad and the Philadelphia and Reading Railway adopted 11   kV 25   Hz single-phase AC. Parts of the original electrified network still operate at 25   Hz, with voltage boosted to 12   kV, while others were converted to 12.5 or 25   kV 60   Hz. In

1748-447: Is sufficient traffic, the reduced track and especially the lower engine maintenance and running costs exceed the costs of this maintenance significantly. Newly electrified lines often show a "sparks effect", whereby electrification in passenger rail systems leads to significant jumps in patronage / revenue. The reasons may include electric trains being seen as more modern and attractive to ride, faster, quieter and smoother service, and

1840-410: Is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driving auxiliary machinery. More recently, the development of very high power semiconductors has caused the classic DC motor to be largely replaced with

1932-894: Is the countrywide system. 3   kV DC is used in Belgium, Italy, Spain, Poland, Slovakia, Slovenia, South Africa, Chile, the northern portion of the Czech Republic, the former republics of the Soviet Union , and in the Netherlands on a few kilometers between Maastricht and Belgium. It was formerly used by the Milwaukee Road from Harlowton, Montana , to Seattle, across the Continental Divide and including extensive branch and loop lines in Montana, and by

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2024-580: Is the development of powering trains and locomotives using electricity instead of diesel or steam power . The history of railway electrification dates back to the late 19th century when the first electric tramways were introduced in cities like Berlin , London , and New York City . In 1881, the first permanent railway electrification in the world was the Gross-Lichterfelde Tramway in Berlin , Germany. Overhead line electrification

2116-462: Is the most heavily traveled section on the entire Metra system. At 55th-56th-57th Street , passengers may transfer between main line and South Chicago/Blue Island branch services, as well as to South Shore Line service to Indiana. The Metra Electric District has the best on-time performance of all Metra lines, averaging only one late train a month in 2014. Trains operate at a maximum speed of 65 miles per hour (105 km/h); as of February 2024, work

2208-420: 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 . Power is supplied to moving trains with

2300-607: Is underway to increase the maximum speed to 79 miles per hour (127 km/h), with an increase to 90 miles per hour (140 km/h) in certain sections potentially following. The line was built by the Illinois Central Railroad, one of the first commuter services outside the major metropolitan areas of the northeastern United States. It opened on July 21, 1856 between the IC's then-downtown station, Great Central Station , (now Millennium Station) and Hyde Park . Part of

2392-838: Is used on some narrow-gauge lines in Japan. On "French system" HSLs, the overhead line and a "sleeper" feeder line each carry 25   kV in relation to the rails, but in opposite phase so they are at 50   kV from each other; autotransformers equalize the tension at regular intervals. Various railway electrification systems in the late nineteenth and twentieth centuries utilised three-phase , rather than single-phase electric power delivery due to ease of design of both power supply and locomotives. These systems could either use standard network frequency and three power cables, or reduced frequency, which allowed for return-phase line to be third rail, rather than an additional overhead wire. The majority of modern electrification systems take AC energy from

2484-511: The COVID-19 pandemic , ridership dropped to 2,019,403 passengers in 2020 and to 1,836,723 in 2021. The Metra Electric District uses second-generation bi-level Highliner multiple unit cars built by Nippon Sharyo . These will be supplemented by additional EMUs built at Nippon Sharyo's new Rochelle, Illinois facility opened in 2012. In 2005, these began to replace the original Highliner fleet built by St. Louis Car Company and Bombardier in

2576-656: The Delaware, Lackawanna and Western Railroad (now New Jersey Transit , converted to 25   kV   AC) in the United States, and the Kolkata suburban railway (Bardhaman Main Line) in India, before it was converted to 25   kV 50   Hz. DC voltages between 600   V and 750   V are used by most tramways and trolleybus networks, as well as some metro systems as the traction motors accept this voltage without

2668-711: The HSL-Zuid and Betuwelijn , and 3,000   V south of Maastricht . In Portugal, it is used in the Cascais Line and in Denmark on the suburban S-train system (1650   V DC). In the United Kingdom, 1,500   V   DC was used in 1954 for the Woodhead trans-Pennine route (now closed); the system used regenerative braking , allowing for transfer of energy between climbing and descending trains on

2760-701: The Innovia ART system. While part of the SkyTrain network, the Canada Line does not use this system and instead uses more traditional motors attached to the wheels and third-rail electrification. A few lines of the Paris Métro in France operate on a four-rail power system. The trains move on rubber tyres which roll on a pair of narrow roll ways made of steel and, in some places, of concrete . Since

2852-619: The Regional Transportation Authority signed a contract with Illinois Central Gulf to fund its commuter service. The next year an extension of 2.3 miles (3.7 km) was built to the current terminal at University Park (originally named Park Forest South). On May 1, 1987 Metra bought the line and its branches for $ 28 million ($ 75.1 million adjusted for inflation). The line is now operated by Northeast Illinois Regional Commuter Rail Corporation, Metra's operating subsidiary. Two inter-city freight tracks retained by

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2944-636: The Southern Railway serving Coulsdon North and Sutton railway station . The lines were electrified at 6.7   kV 25   Hz. It was announced in 1926 that all lines were to be converted to DC third rail and the last overhead-powered electric service ran in September 1929. AC power is used at 60   Hz in North America (excluding the aforementioned 25   Hz network), western Japan, South Korea and Taiwan; and at 50   Hz in

3036-461: The United States , the New York, New Haven and Hartford Railroad was one of the first major railways to be electrified. Railway electrification continued to expand throughout the 20th century, with technological improvements and the development of high-speed trains and commuters . Today, many countries have extensive electrified railway networks with 375 000  km of standard lines in

3128-554: The 1970s. On February 12, 2016, the original Highliners left on their last run in revenue service. Metra confirmed in a Facebook post that twenty-four cars are being sent to museums around the Midwestern United States, including the Illinois Railway Museum, while an unconfirmed source stated that some cars were sent to Mendota, Illinois to be scrapped. The branch leaves the mainline south of

3220-704: The Canadian National Railroad. Off-peak and Saturday service is frequent, while Sunday service operates hourly north of 63rd Street and every 2 hours south of 63rd. On January 4, 2021, fares on the Metra Electric line, along with the Rock Island line , were cut in half for all passengers. The proposed Gold Line, derived from the earlier and more extensive Gray Line plan would have the Electric District operate more like

3312-556: The Electric District only pick up passengers heading eastbound (outbound from Chicago) and only discharge passengers heading westbound (inbound to the city). The Electric District has more frequent service than any other Metra line. As of August 2023, Metra operates 131 trains (64 inbound and 67 outbound) on the line on weekdays. On the main line, 27 inbound trains originate from University Park , four from Homewood , and three from Kensington/115th Street , while three outbound trains terminate at Kensington/115th Street, four at Homewood, and

3404-603: The Gold Line was proposed, the idea of providing rapid transit service along Chicago's south lakefront has gained considerable support from neighborhoods along its route. Despite its popular support, officials from CTA and Metra have largely dismissed the plan, focusing on other expansion projects. In response to this and other concerns, in 2009 the RTA and the Chicago Department of Transportation authorized $ 450,000 for

3496-718: The Hyde Park stations every 20 minutes on weekdays until 7 p.m. and every half-hour on Saturdays. The proposed schedule also calls for boosting service on the main line from 63rd Street to Kensington, from every two hours to every hour. However, the proposed schedule also calls for the elimination of lightly used Blue Island trains, including all Saturday service. After reviewing community feedback, Metra decided to keep four Saturday Blue Island trains and one late night trip to South Chicago. The new service went into effect September 11, 2017. Between 2014 and 2019, annual ridership declined 23% from 9.4 million to 7.3 million passengers. Due to

3588-612: The IC and the Chicago city government collaborated to build a berm from the far south suburb of Homewood into the city. They also dug a trench from the near south side into the city proper, eliminating all grade crossings on the main line except one just south of the Richton Park station. The University Park extension required the line to cross a very long private driveway. The South Chicago branch runs at grade, crossing many city streets. The grade crossing elimination project

3680-757: The ICG are now part of the Canadian National Railway , used by Amtrak 's City of New Orleans , Illini and Saluki trains. From 1988 onward, Randolph Street Terminal was under near-perpetual construction. The construction of Millennium Park moved the station completely underground, and in 2005 it was renamed Millennium Station. The Metra Electric is the only line on the Metra system in which all stations (except 18th and 47th Streets, both flag stops ) have ticket vending machines. The machines originally sold magnetically encoded tickets which unlocked

3772-570: The Illinois Central, Michigan Central , Burlington Route , and Galena and Chicago Union (a predecessor to the Chicago and North Western ). The G&CU was a tenant for less than a year, while the Burlington moved to the new Union Depot (predecessor to today's Union Station) in 1881. Predecessors of the Cleveland, Cincinnati, Chicago and St. Louis Railway (the "Big Four") reached the depot in 1872 via trackage rights from Kankakee. The depot

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3864-414: The Metra Electric schedule is the similarity of the weekday and Saturday timetables. Many express trains run throughout the day in both directions. On other Metra lines, express service operates exclusively during the morning and afternoon rush hours. It is the only Metra line where all trackage is used exclusively for commuter service. Freight trains and Amtrak trains run on a pair of adjacent tracks owned by

3956-717: The Netherlands, New Zealand ( Wellington ), Singapore (on the North East MRT line ), the United States ( Chicago area on the Metra Electric district and the South Shore Line interurban line and Link light rail in Seattle , Washington). In Slovakia, there are two narrow-gauge lines in the High Tatras (one a cog railway ). In the Netherlands it is used on the main system, alongside 25   kV on

4048-473: The South Chicago branch, and four on the Blue Island branch. On Sunday and holidays, Metra operates 22 trains on the line, with 12 roundtrips operating on the main line to University Park and 10 trains operating on the South Chicago branch. Service on the Blue Island branch is suspended during these times. The trunk stretch of the line shared between all branches from Millennium Station to 63rd Street

4140-745: The UK, the London, Brighton and South Coast Railway pioneered overhead electrification of its suburban lines in London, London Bridge to Victoria being opened to traffic on 1   December 1909. Victoria to Crystal Palace via Balham and West Norwood opened in May 1911. Peckham Rye to West Norwood opened in June 1912. Further extensions were not made owing to the First World War. Two lines opened in 1925 under

4232-494: The ability to pull freight at higher speed over gradients; in mixed traffic conditions this increases capacity when the time between trains can be decreased. The higher power of electric locomotives and an electrification can also be a cheaper alternative to a new and less steep railway if train weights are to be increased on a system. On the other hand, electrification may not be suitable for lines with low frequency of traffic, because lower running cost of trains may be outweighed by

4324-491: The actual route itself (the only exceptions perhaps being occasional work or repair trains). The line is the only one in the Metra system with more than one station in Downtown Chicago, the only line with no stations in fare zone 4, and also has the highest number of stations (49) of any Metra line. It is the only Metra line powered by overhead lines , the only line with high-level platforms and level boarding, and

4416-516: The advantages of raising the voltage is that, to transmit certain level of power, lower current is necessary ( P = V × I ). Lowering the current reduces the ohmic losses and allows for less bulky, lighter overhead line equipment and more spacing between traction substations, while maintaining power capacity of the system. On the other hand, the higher voltage requires larger isolation gaps, requiring some elements of infrastructure to be larger. The standard-frequency AC system may introduce imbalance to

4508-462: The bi-level train. A major contributing factor was that Illinois Central Gulf used a dark gray color scheme on the front ends of the Highliner fleet, which was very difficult to see on the cloudy morning of the accident. After the accident the ends of all of the ICG 1926 heavyweight still in use and Highliner MU fleet were partially painted with bright orange added for additional visibility. In 1976

4600-410: The distance they could transmit power. However, in the early 20th century, alternating current (AC) power systems were developed, which allowed for more efficient power transmission over longer distances. In the 1920s and 1930s, many countries worldwide began to electrify their railways. In Europe, Switzerland , Sweden , France , and Italy were among the early adopters of railway electrification. In

4692-406: The early 1880s, and from Kensington southwest to Blue Island in the early 1890s, both later electrified along with the main line. When the IC moved its intercity operations to Central Station in 1893, it built Randolph Street Terminal on the former site of Great Central to handle its growing commuter operations. By the early 20th century the IC operated up to 300 steam trains each day. In 1919,

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4784-448: The electrification. Electric vehicles, especially locomotives, lose power when traversing gaps in the supply, such as phase change gaps in overhead systems, and gaps over points in third rail systems. These become a nuisance if the locomotive stops with its collector on a dead gap, in which case there is no power to restart. This is less of a problem in trains consisting of two or more multiple units coupled together, since in that case if

4876-404: The end of funding. Most electrification systems use overhead wires, but third rail is an option up to 1,500   V. Third rail systems almost exclusively use DC distribution. The use of AC is usually not feasible due to the dimensions of a third rail being physically very large compared with the skin depth that AC penetrates to 0.3 millimetres or 0.012 inches in a steel rail. This effect makes

4968-591: The experiment was curtailed. In 1970 the Ural Electromechanical Institute of Railway Engineers carried out calculations for railway electrification at 12 kV DC , showing that the equivalent loss levels for a 25 kV AC system could be achieved with DC voltage between 11 and 16   kV. In the 1980s and 1990s 12 kV DC was being tested on the October Railway near Leningrad (now Petersburg ). The experiments ended in 1995 due to

5060-500: The fact that electrification often goes hand in hand with a general infrastructure and rolling stock overhaul / replacement, which leads to better service quality (in a way that theoretically could also be achieved by doing similar upgrades yet without electrification). Whatever the causes of the sparks effect, it is well established for numerous routes that have electrified over decades. This also applies when bus routes with diesel buses are replaced by trolleybuses. The overhead wires make

5152-433: The former 67th Street station. The branch leaves the main line south of Kensington/115th Street . Railway electrification system Railway electrification is the use of electric power for the propulsion of rail transport . Electric railways use either electric locomotives (hauling passengers or freight in separate cars), electric multiple units ( passenger cars with their own motors) or both. Electricity

5244-1012: The general power grid. This is especially useful in mountainous areas where heavily loaded trains must descend long grades. Central station electricity can often be generated with higher efficiency than a mobile engine/generator. While the efficiency of power plant generation and diesel locomotive generation are roughly the same in the nominal regime, diesel motors decrease in efficiency in non-nominal regimes at low power while if an electric power plant needs to generate less power it will shut down its least efficient generators, thereby increasing efficiency. The electric train can save energy (as compared to diesel) by regenerative braking and by not needing to consume energy by idling as diesel locomotives do when stopped or coasting. However, electric rolling stock may run cooling blowers when stopped or coasting, thus consuming energy. Large fossil fuel power stations operate at high efficiency, and can be used for district heating or to produce district cooling , leading to

5336-411: The high cost of the electrification infrastructure. Therefore, most long-distance lines in developing or sparsely populated countries are not electrified due to relatively low frequency of trains. Network effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of

5428-715: The line was elevated for the World's Columbian Exposition of 1893 in Jackson Park . The line predates the 1871 Great Chicago Fire , and ran on a trestle just offshore in Lake Michigan . After the fire, remains of buildings destroyed by the fire were dumped into the lake, creating landfill that forms the foundation of Grant Park , which the Metra Electric District runs through. Two branches were added: from Brookdale southeast to South Chicago in

5520-497: The losses (saving 2   GWh per year per 100   route-km; equalling about €150,000 p.a.). The line chosen is one of the lines, totalling 6000   km, that are in need of renewal. In the 1960s the Soviets experimented with boosting the overhead voltage from 3 to 6   kV. DC rolling stock was equipped with ignitron -based converters to lower the supply voltage to 3   kV. The converters turned out to be unreliable and

5612-422: The maximum power that can be transmitted, also can be responsible for electrochemical corrosion due to stray DC currents. Electric trains need not carry the weight of prime movers , transmission and fuel. This is partly offset by the weight of electrical equipment. Regenerative braking returns power to the electrification system so that it may be used elsewhere, by other trains on the same system or returned to

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5704-469: The morning rush hour, overshot the 27th Street platform and backed up into the station. The bi-level train had already tripped the signals to green for the next train, an older, heavy steel single-level express train. As the bi-level train was backing up at 11 miles per hour (18 km/h), it was struck by the single-level train at full speed. The single-level train telescoped the bi-level train, killing 45 passengers and injuring hundreds more, primarily in

5796-402: The need for overhead wires between those stations. Maintenance costs of the lines may be increased by electrification, but many systems claim lower costs due to reduced wear-and-tear on the track from lighter rolling stock. There are some additional maintenance costs associated with the electrical equipment around the track, such as power sub-stations and the catenary wire itself, but, if there

5888-514: The only line with three service branches. Trains operate on 1,500 V DC . The main line north of Kensington/115th Street is shared with the Northern Indiana Commuter Transportation District (NICTD)'s South Shore Line , an electric interurban line through northern Indiana to South Bend . Per a longstanding non-compete agreement, South Shore trains stopping at stations shared with

5980-505: The phase separation between the electrified sections powered from different phases, whereas high voltage would make the transmission more efficient. UIC conducted a case study for the conversion of the Bordeaux-Hendaye railway line (France), currently electrified at 1.5   kV DC, to 9   kV DC and found that the conversion would allow to use less bulky overhead wires (saving €20 million per 100   route-km) and lower

6072-508: The problem by insulating the running rails from the current return should there be a leakage through the running rails. The Expo and Millennium Line of the Vancouver SkyTrain use side-contact fourth-rail systems for their 650 V DC supply. Both are located to the side of the train, as the space between the running rails is occupied by an aluminum plate, as part of stator of the linear induction propulsion system used on

6164-566: The remaining 26 at University Park. There are also 20 inbound and 22 outbound trains on the South Chicago (93rd Street) branch, as well as ten inbound and 12 outbound trains on the Blue Island branch (one outbound train to Blue Island, No. 245, originates from Kensington/115th Street, not Millennium Station ). On Saturdays, Metra operates 41 roundtrip trains on the line, including 21 on the main line to University Park, 16 trains on

6256-465: The resistance per unit length unacceptably high compared with the use of DC. Third rail is more compact than overhead wires and can be used in smaller-diameter tunnels, an important factor for subway systems. The London Underground in England is one of few networks that uses a four-rail system. The additional rail carries the electrical return that, on third-rail and overhead networks, is provided by

6348-570: The revenue obtained for freight and passenger traffic. Different systems are used for urban and intercity areas; some electric locomotives can switch to different supply voltages to allow flexibility in operation. Six of the most commonly used voltages have been selected for European and international standardisation. Some of these are independent of the contact system used, so that, for example, 750   V   DC may be used with either third rail or overhead lines. There are many other voltage systems used for railway electrification systems around

6440-498: The running rails. On the London Underground, a top-contact third rail is beside the track, energized at +420 V DC , and a top-contact fourth rail is located centrally between the running rails at −210 V DC , which combine to provide a traction voltage of 630 V DC . The same system was used for Milan 's earliest underground line, Milan Metro 's line 1 , whose more recent lines use an overhead catenary or

6532-467: The same task: converting and transporting high-voltage AC from the power grid to low-voltage DC in the locomotive. The difference between AC and DC electrification systems lies in where the AC is converted to DC: at the substation or on the train. Energy efficiency and infrastructure costs determine which of these is used on a network, although this is often fixed due to pre-existing electrification systems. Both

6624-590: The service "visible" even in no bus is running and the existence of the infrastructure gives some long-term expectations of the line being in operation. Due to the height restriction imposed by the overhead wires, double-stacked container trains have been traditionally difficult and rare to operate under electrified lines. However, this limitation is being overcome by railways in India, China and African countries by laying new tracks with increased catenary height. Great Central Station The station proved inadequate to handle growing traffic and its original building

6716-569: The steep approaches to the tunnel. The system was also used for suburban electrification in East London and Manchester , now converted to 25   kV   AC. It is now only used for the Tyne and Wear Metro . In India, 1,500   V DC was the first electrification system launched in 1925 in Mumbai area. Between 2012 and 2016, the electrification was converted to 25   kV 50   Hz, which

6808-443: The supply grid, requiring careful planning and design (as at each substation power is drawn from two out of three phases). The low-frequency AC system may be powered by separate generation and distribution network or a network of converter substations, adding the expense, also low-frequency transformers, used both at the substations and on the rolling stock, are particularly bulky and heavy. The DC system, apart from being limited as to

6900-694: The three-phase induction motor fed by a variable frequency drive , a special inverter that varies both frequency and voltage to control motor speed. These drives can run equally well on DC or AC of any frequency, and many modern electric locomotives are designed to handle different supply voltages and frequencies to simplify cross-border operation. Five European countries – Germany, Austria, Switzerland, Norway and Sweden – have standardized on 15   kV 16 + 2 ⁄ 3   Hz (the 50   Hz mains frequency divided by three) single-phase AC. On 16 October 1995, Germany, Austria and Switzerland changed from 16 + 2 ⁄ 3   Hz to 16.7   Hz which

6992-575: The through traffic to non-electrified lines. If through traffic is to have any benefit, time-consuming engine switches must occur to make such connections or expensive dual mode engines must be used. This is mostly an issue for long-distance trips, but many lines come to be dominated by through traffic from long-haul freight trains (usually running coal, ore, or containers to or from ports). In theory, these trains could enjoy dramatic savings through electrification, but it can be too costly to extend electrification to isolated areas, and unless an entire network

7084-478: The timetable accents for the Metra Electric District are printed in bright "Panama orange" to reflect the line's origins with the Illinois Central Railroad (IC) and its Panama Limited passenger train . Apart from the spots where its tracks run parallel to other main lines, it is the only Metra line running entirely on dedicated passenger tracks, with no freight trains operating anywhere on

7176-469: The train shed was the three masonry arches fronting the wooden structure. Architectural historian Carroll Meeks criticized the front of the head house, calling it an "ill-assorted complex of disparate elements." Carl W. Condit cited the design as an example of vernacular architecture . The train shed incorporated a Howe truss in its design and measured 166 feet (51 m) wide and 36 feet (11 m) high. Only Birmingham New Street railway station had

7268-466: The train stops with one collector in a dead gap, another multiple unit can push or pull the disconnected unit until it can again draw power. The same applies to the kind of push-pull trains which have a locomotive at each end. Power gaps can be overcome in single-collector trains by on-board batteries or motor-flywheel-generator systems. In 2014, progress is being made in the use of large capacitors to power electric vehicles between stations, and so avoid

7360-713: The train's kinetic energy back into electricity and returns it to the supply system to be used by other trains or the general utility grid. While diesel locomotives burn petroleum products, electricity can be generated from diverse sources, including renewable energy . Historically, concerns of resource independence have played a role in the decision to electrify railway lines. The landlocked Swiss confederation which almost completely lacks oil or coal deposits but has plentiful hydropower electrified its network in part in reaction to supply issues during both World Wars. Disadvantages of electric traction include: high capital costs that may be uneconomic on lightly trafficked routes,

7452-413: The transmission and conversion of electric energy involve losses: ohmic losses in wires and power electronics, magnetic field losses in transformers and smoothing reactors (inductors). Power conversion for a DC system takes place mainly in a railway substation where large, heavy, and more efficient hardware can be used as compared to an AC system where conversion takes place aboard the locomotive where space

7544-588: The turnstiles. People with paper tickets or weekend passes, on reduced fares or who had trouble with the vending machines had to use a blue or orange pal phone to contact an operator who would unlock the turnstiles. Complaints from passengers who missed their trains caused Metra to remove the turnstiles in November 2003. The main line and South Chicago branch run daily, but the Blue Island Branch does not operate on Sundays or holidays. A unique feature of

7636-470: The tyres do not conduct the return current, the two guide bars provided outside the running ' roll ways ' become, in a sense, a third and fourth rail which each provide 750 V DC , so at least electrically it is a four-rail system. Each wheel set of a powered bogie carries one traction motor . A side sliding (side running) contact shoe picks up the current from the vertical face of each guide bar. The return of each traction motor, as well as each wagon ,

7728-432: The voltage, the lower the current for the same power (because power is current multiplied by voltage), and power loss is proportional to the current squared. The lower current reduces line loss, thus allowing higher power to be delivered. As alternating current is used with high voltages. Inside the locomotive, a transformer steps the voltage down for use by the traction motors and auxiliary loads. An early advantage of AC

7820-405: The weight of an on-board transformer. Increasing availability of high-voltage semiconductors may allow the use of higher and more efficient DC voltages that heretofore have only been practical with AC. The use of medium-voltage DC electrification (MVDC) would solve some of the issues associated with standard-frequency AC electrification systems, especially possible supply grid load imbalance and

7912-532: The world, and the list of railway electrification systems covers both standard voltage and non-standard voltage systems. The permissible range of voltages allowed for the standardised voltages is as stated in standards BS   EN   50163 and IEC   60850. These take into account the number of trains drawing current and their distance from the substation. 1,500   V DC is used in Japan, Indonesia, Hong Kong (parts), Ireland, Australia (parts), France (also using 25 kV 50 Hz AC ) ,

8004-534: The world, including China , India , Japan , France , Germany , and the United Kingdom . Electrification is seen as a more sustainable and environmentally friendly alternative to diesel or steam power and is an important part of many countries' transportation infrastructure. Electrification systems are classified by three main parameters: Selection of an electrification system is based on economics of energy supply, maintenance, and capital cost compared to

8096-409: Was demolished in 1893 in favor of the new Central Station at the southern end of Grant Park . Although it continued to receive some traffic, over time it increasingly became a commuter rail depot. Millennium Station , formerly Randolph Street Terminal, sits on the location. The station was designed by Otto H. Matz and included both a head house and a train shed . The most distinctive feature of

8188-437: Was exacerbated because the return current also had a tendency to flow through nearby iron pipes forming the water and gas mains. Some of these, particularly Victorian mains that predated London's underground railways, were not constructed to carry currents and had no adequate electrical bonding between pipe segments. The four-rail system solves the problem. Although the supply has an artificially created earth point, this connection

8280-553: Was first applied successfully by Frank Sprague in Richmond, Virginia in 1887-1888, and led to the electrification of hundreds of additional street railway systems by the early 1890s. The first electrification of a mainline railway was the Baltimore and Ohio Railroad's Baltimore Belt Line in the United States in 1895–96. The early electrification of railways used direct current (DC) power systems, which were limited in terms of

8372-495: Was followed by electrification. The IC electrified the commuter tracks in 1926, from downtown to Matteson . In addition to the removal of all grade crossings, the tracks were separated from, and moved to the west side of, the two freight and inter-city tracks. At McCormick Place just south of downtown Chicago, the two non-electrified tracks to Central Station crossed over the new electric alignment. The electric tracks continued north to Randolph Street Terminal. The "IC Electric"

8464-414: Was once Chicago's busiest suburban railroad, and carried a great deal of traffic within the city as well as to suburban communities. The three lines carried 26 million passengers in 1927, the first full year of electrified operation. Ridership rose to 35 million in 1929, and reached an all-time peak of 47 million in 1946. Service was extended 1.1 miles (1.8 km) southward from Matteson to Richton Park ,

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