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Electric locomotive

technology Maturity 11-13 Next article →

An electric locomotive is a specialized machine designed to pull trains using electricity. Unlike diesel locomotives, which burn fuel on board, these machines draw power from external sources. This electricity can come from overhead lines or a third rail located near the tracks. Some models also use on-board energy storage, such as batteries or supercapacitors. It is important to distinguish these from diesel-electric locomotives. In a diesel-electric system, a fuel-burning engine only acts as a generator to create electricity. In a true electric locomotive, the electricity comes from the rail network itself.

Pantograaf lichtrail
Pantograaf lichtrail

The efficiency of these machines is one of their greatest strengths. Electric motors often reach an efficiency level above 90%. Modern locomotives frequently use AC motor-inverter drive systems to manage this power. These systems allow for a process called regenerative braking. During braking, the kinetic energy of the moving train is converted back into electricity. This recovered power is then sent back into the electrical lines for other trains to use.

ÖBB 1216.233
ÖBB 1216.233

Electric locomotives offer several operational advantages over their diesel counterparts. They are much quieter because they lack large combustion engines and exhaust noise. Because they have fewer reciprocating parts, they also cause less wear and tear on the tracks. This helps reduce the amount of track maintenance required. Furthermore, power plants can provide much more energy than a single locomotive could ever carry. This allows electric locomotives to achieve higher power outputs and greater surge power for fast acceleration.

While these machines are efficient, the infrastructure required to support them is very expensive. Building overhead lines, third rails, substations, and control systems requires massive investment. In the United States, public policy can make electrification difficult. For instance, privately owned rail facilities may face higher property taxes if they choose to electrify. In contrast, many European countries view railway networks as part of the national transport infrastructure. This allows the state to finance the large investments needed for electrification.

WMATA third rail at West Falls Church
WMATA third rail at West Falls Church

The history of electric traction began in the mid-19th century. The first known electric locomotive was built in 1837 by Robert Davidson in Aberdeen. His vehicle used galvanic cells, which are early forms of batteries, to power two reluctance motors. Although it could haul a six-ton load, the limited power of the batteries prevented widespread use. Later, in 1879, Werner von Siemens presented the first electric passenger train in Berlin. This system used 150 V DC supplied through an insulated third rail.

1879 Siemens & Halske Wernerwerk Electric locomotive
1879 Siemens & Halske Wernerwerk Electric locomotive

As cities grew, the need for electric trains increased due to the problems caused by steam. Smoke from steam engines was noxious and difficult to manage in tunnels. The City and South London Railway opened in 1890 as the first electrically worked underground line. In the United States, the Baltimore Belt Line began using electric locomotives in 1895 to navigate tunnels. By 1904, the New York Central Railroad also began electric operations following laws that limited smoke-generating engines.

B&O 1895 loco
B&O 1895 loco

Technological shifts also occurred between Direct Current (DC) and Alternating Current (AC) systems. Charles Brown designed the first practical AC locomotive using three-phase AC. He found that three-phase motors had a higher power-to-weight ratio than DC motors. In 1901, the Italian railways became the first to use electric traction for an entire mainline. This was the 106 km Valtellina line.

Ganz engine Valtellina
Ganz engine Valtellina

Another major advancement came from the Hungarian engineer Kálmán Kandó. In 1894, he developed new types of three-phase asynchronous electric drive motors. In 1918, Kandó invented the rotary phase converter. This device allowed locomotives to use three-phase motors while drawing power from a single overhead wire. This innovation enabled locomotives to use the standard industrial frequency AC from national power networks. Today, electric locomotives remain essential for commuter rail and high-traffic freight routes.

Locomotiva E656-569
Locomotiva E656-569
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🖼️ Images & Media (28)
File:Locomotive ChS4-109 2012 G1.jpg
Locomotive ChS4-109 2012 G1.jpg
File:ÖBB 1216.233.JPG
ÖBB 1216.233.JPG
File:Due locomotive E464 alla stazione FS di Formia-Gaeta.jpg
Due locomotive E464 alla stazione FS di...
File:1879 Siemens & Halske Wernerwerk Electric locomotive.jpg
1879 Siemens & Halske Wernerwerk Electric...
File:B&O 1895 loco.png
B&O 1895 loco.png
File:AlcoGEClassS1.JPG
AlcoGEClassS1.JPG
File:MILW ES-2.jpg
MILW ES-2.jpg
File:Ganz engine Valtellina.jpg
Ganz engine Valtellina.jpg
File:Biaschina Intermodal.jpg
Biaschina Intermodal.jpg
File:Finlaysonin sähköveturi Pikku-Pässi 1950-luvulla. Kuva Vapriikin kuva-arkisto. (16408774116).jpg
Finlaysonin sähköveturi Pikku-Pässi...
File:Vivan755.jpg
Vivan755.jpg
File:DC Electric Locomotive.jpg
DC Electric Locomotive.jpg

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