Misplaced Pages

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86-602: The EP-1 had to support two electric systems and three collection methods . The New York Central Railroad 's 660 V third rail DC extended from Grand Central to Woodlawn , where New Haven territory began. Westinghouse installed 11 kV overhead line AC from Woodlawn to Stamford. Finally, the New York Central employed overhead lines over railroad switches in place of third rail electrification. To support these myriad methods, Westinghouse installed two sets of pantographs , one for AC and one for DC collection, and

172-420: A contact shoe for third rail operation. Control devices within the locomotive prevented drawing power from multiple sources and enabled transition between them without stopping. The boxcab body was 37 feet 6 + 1 ⁄ 2  inches (11.443 m) long and weighed 102 short tons (93 t). Beneath it, initially, were four axles in a pair of trucks ( B-B arrangement). After oscillation problems

258-577: A gas mask . Diesel exhaust is the exhaust gas produced by a diesel engine , plus any contained particulates . Its composition may vary with the fuel type, rate of consumption or speed of engine operation (e.g., idling or at speed or under load), and whether the engine is in an on-road vehicle, farm vehicle, locomotive, marine vessel, or stationary generator or other application. Diesel exhaust causes lung cancer and other diseases such as asthma , and many premature deaths. Methods exist to reduce nitrogen oxides (NO x ) and particulate matter (PM) in

344-510: A tailpipe filter installed, while the United States has mandated it for diesel only. In 2022, British testing specialist Emissions Analytics estimated that the 300 million or so gasoline vehicles in the US over the subsequent decade would emit around 1.6 septillion harmful particles. Carbon dioxide is a greenhouse gas . Motor vehicle CO 2 emissions are part of the anthropogenic contribution to

430-402: 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

516-420: A catalytic converter up to 100,000 ppm (10%) for a richly tuned carburetor engine, such as typically found on small generators and garden equipment. Exhaust gas from an internal combustion engine whose fuel includes nitromethane will contain nitric acid vapour, which is corrosive, and when inhaled causes a muscular reaction making it impossible to breathe. People who are likely to be exposed to it should wear

602-573: 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

688-467: 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

774-468: 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

860-454: 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

946-498: 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

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1032-481: 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

1118-418: 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

1204-539: Is colorless, odorless and tasteless, but highly toxic. It combines with hemoglobin to produce carboxyhemoglobin , which blocks the transport of oxygen. At concentrations above 1000ppm it is considered immediately dangerous and is the most immediate health hazard from running engines in a poorly ventilated space. In 2011, 52% of carbon monoxide emissions were created by mobile vehicles in the U.S. Chronic (long-term) exposure to benzene ( C 6 H 6 ) damages bone marrow . It can also cause excessive bleeding and depress

1290-411: 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

1376-451: 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

1462-526: 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

1548-591: Is emitted as a result of the combustion of fuels such as natural gas , gasoline (petrol) , diesel fuel , fuel oil , biodiesel blends, or coal . According to the type of engine, it is discharged into the atmosphere through an exhaust pipe , flue gas stack , or propelling nozzle . It often disperses downwind in a pattern called an exhaust plume . It is a major component of motor vehicle emissions (and from stationary internal combustion engines ), which can also include crankcase blow-by and evaporation of unused gasoline. Air pollution from burning fossil fuels

1634-707: Is estimated to kill over 5 million people each year. A 2013 study by the Massachusetts Institute of Technology (MIT) indicates that 53,000 early deaths occur per year in the United States alone because of vehicle emissions. According to another study from the same university, traffic fumes alone cause the death of 5,000 people every year just in the United Kingdom. Researchers from the University of California, Los Angeles School of Public Health say preliminary results of their statistical study of children listed in

1720-552: Is estimated to kill over 5 million people each year. Motor vehicle emissions are a common source of air pollution and are a major ingredient in the creation of smog in some large cities. The largest part of most combustion gas is nitrogen (N 2 ), water vapor (H 2 O) (except with pure-carbon fuels), and carbon dioxide (CO 2 ) (except for fuels without carbon); these are not toxic or noxious (although water vapor and carbon dioxide are greenhouse gases that contribute to climate change ). A relatively small part of combustion gas

1806-435: Is important to the functioning of the catalytic converter of an internal combustion engine . It may be measured by an exhaust gas temperature gauge . EGT is also a measure of engine health in gas-turbine engines (see below). During the first two minutes after starting the engine of a car that has not been operated for several hours, the amount of emissions can be very high. This occurs for two main reasons: Comparable with

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1892-486: 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

1978-710: 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

2064-447: 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

2150-534: Is that emitted from ovens, furnaces and boilers. In steam engine terminology the exhaust is steam that is now so low in pressure that it can no longer do useful work. Mono- nitrogen oxides NO and NO 2 ( NOx ) (whether produced this way or naturally by lightning ) react with ammonia , moisture, and other compounds to form nitric acid vapor and related particles. Small particles can penetrate deeply into sensitive lung tissue and damage it, causing premature death in extreme cases. Inhalation of NO species increases

2236-410: 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

2322-850: 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

2408-565: 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

2494-420: 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

2580-404: Is undesirable, noxious, or toxic substances, such as carbon monoxide (CO) from incomplete combustion, hydrocarbons (properly indicated as C x H y , but typically shown simply as "HC" on emissions-test slips) from unburnt fuel, nitrogen oxides (NO x ) from excessive combustion temperatures, and particulate matter (mostly soot ) from incomplete combustion. Exhaust gas temperature (EGT)

2666-834: 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

New Haven EP-1 - Misplaced Pages Continue

2752-440: Is useful to growing plants. When oxides of nitrogen (NOx) and volatile organic compounds (VOCs) react in the presence of sunlight, ground level ozone is formed, a primary ingredient in smog . A 2005 U.S. EPA report gives road vehicles as the second largest source of VOCs in the U.S. at 26% and 19% are from non road equipment which is mostly gasoline and diesel stations. 27% of VOC emissions are from solvents which are used in

2838-638: 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

2924-596: The European emission standards EURO III as it was applied in October 2000 In 2000, the United States Environmental Protection Agency began to implement more stringent emissions standards for light duty vehicles. The requirements were phased in beginning with 2004 vehicles and all new cars and light trucks were required to meet the updated standards by the end of 2007. In spark-ignition engines

3010-626: 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

3096-674: 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

3182-616: 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

3268-454: 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

3354-410: The immune system , increasing the chance of infection . Benzene causes leukemia and is associated with other blood cancers and pre-cancers of the blood. The health effects of inhaling airborne particulate matter have been widely studied in humans and animals and include asthma , lung cancer , cardiovascular issues, premature death . Because of the size of the particles, they can penetrate

3440-684: 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

3526-534: The New Haven added an unpowered axle to each end (1-B-B-1), which resolved the issue. The EP-1 was capable of multiple working , and was the first electric locomotive to do so regularly. Westinghouse delivered the first prototype in 1905, followed by 34 production units in 1907–1908. One was loaned to the Pennsylvania Railroad in 1907 for testing on the West Jersey and Seashore Railroad ; the locomotive tested well but

New Haven EP-1 - Misplaced Pages Continue

3612-493: The Pennsylvania adopted DC electrification for its New York Tunnel Extension . The New Haven ordered six more in 1908. The EP-1 designation, applied later, stood for "Electric Passenger." The EP-1s handled passenger trains between New York and Stamford, and later New Haven, Connecticut , when the New Haven extended electrification there. Retirements began in 1936 as equipment wore out and newer locomotives became available, but

3698-720: 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

3784-494: 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

3870-516: 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

3956-452: The deepest part of the lungs. A 2011 UK study estimates 90 deaths per year due to passenger vehicle PM. In a 2006 publication, the U.S. Federal Highway Administration (FHWA) state that in 2002 about 1 per-cent of all PM 10 and 2 per-cent of all PM 2.5 emissions came from the exhaust of on-road motor vehicles (mostly from diesel engines ). In Chinese, European, and Indian markets, both diesel and gasoline vehicles are required to have

4042-410: 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

4128-448: 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

4214-404: 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

4300-488: The exhaust. In aircraft gas turbine engines, "exhaust gas temperature" (EGT) is a primary measure of engine health. Typically the EGT is compared with a primary engine power indication called "engine pressure ratio" (EPR). For example: at full power EPR there will be a maximum permitted EGT limit. Once an engine reaches a stage in its life where it reaches this EGT limit, the engine will require specific maintenance in order to rectify

4386-571: 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

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4472-500: 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

4558-480: The gases resulting from combustion of the fuel and air mix are called exhaust gases. The composition varies from petrol to diesel engines, but is around these levels: The 10% oxygen for "diesel" is likely if the engine was idling, e.g. in a test rig. It is much less if the engine is running under load, although diesel engines always operate with an excess of air over fuel. The CO content for petrol engines varies from ≈15 ppm for well tuned engine with fuel injection and

4644-1012: 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

4730-580: The growth of CO 2 concentrations in the atmosphere which according to the vast majority of the scientific community is causing climate change . Motor vehicles are calculated to generate about 20% of the European Union's man-made CO 2 emissions, with passenger cars contributing about 12%. European emission standards limit the CO 2 emissions of new passenger cars and light vehicles. The European Union average new car CO 2 emissions figure dropped by 5.4% in

4816-411: 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

4902-574: The last left service in 1947. The New Haven supplemented the EP-1 fleet with 27 EP-2 boxcabs, built between 1919–1927 and 10 EP-3 boxcabs in 1931. No New Haven EP-1s survive today. 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

4988-492: 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

5074-402: The manufacturer of paints and paint thinners and other uses. Ozone is beneficial in the upper atmosphere, but at ground level ozone irritates the respiratory system , causing coughing, choking, and reduced lung capacity. It also has many negative effects throughout the ecosystem. Carbon monoxide poisoning is the most common type of fatal air poisoning in many countries. Carbon monoxide

5160-422: 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

5246-402: 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

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5332-497: 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

5418-407: The pollution of exhaust gases using a catalyst. Scrubbers in ships intend to remove the sulfur dioxide (SO 2 ) of marine exhaust gases. The regulations on marine sulfur dioxide emissions are tightening, however only a small number of special areas worldwide have been designated for low sulfur diesel fuel use only. Air pollution from fossil fuel use by industry, power generation, and transportation

5504-500: 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

5590-430: The problem. The amount the EGT is below the EGT limit is called EGT margin. The EGT margin of an engine will be greatest when the engine is new, or has been overhauled. For most airlines, this information is also monitored remotely by the airline maintenance department by means of ACARS . In jet engines and rocket engines , exhaust from propelling nozzles which in some applications shows shock diamonds . Flue gas

5676-460: 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

5762-570: 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

5848-481: The risk of lung cancer and colorectal cancer. and inhalation of such particles may cause or worsen respiratory diseases such as emphysema and bronchitis and heart disease. In a 2005 U.S. EPA study the largest emissions of NO x came from on road motor vehicles, with the second largest contributor being non-road equipment which is mostly gasoline and diesel stations. The resulting nitric acid may be washed into soil, where it becomes nitrate , which

5934-490: 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

6020-464: 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

6106-528: 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. Exhaust gas Exhaust gas or flue gas

6192-555: 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

6278-443: 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

6364-694: 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

6450-575: 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

6536-466: 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

6622-713: 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,

6708-413: 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

6794-470: 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 ,

6880-432: 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

6966-405: 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

7052-532: 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 ) ,

7138-527: 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

7224-692: The year to the first quarter of 2010, down to 145.6 g/km . Vehicle exhaust contains much water vapour . There has been research into ways that troops in deserts can recover drinkable water from their vehicles' exhaust gases. Emission standards focus on reducing pollutants contained in the exhaust gases from vehicles as well as from industrial flue gas stacks and other air pollution exhaust sources in various large-scale industrial facilities such as petroleum refineries , natural gas processing plants, petrochemical plants and chemical production plants. However, these are often referred to as flue gases . Catalytic converters in cars intend to break down

7310-437: 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

7396-543: 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

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