Railway electrification in Norway
The Norwegian railway network consists of 2,552 kilometers (1,586 mi) of electrified railway lines, constituting 62% of the Norwegian National Rail Administration's 4,114 kilometers (2,556 mi) of line. In 2008, electric traction accounted for 90% of the passenger kilometers, 93% of the tonne kilometers and 74% of the energy consumption of all trains running in Norway, with the rest being accounted for by diesel traction.
Technology for electric railways was demonstrated in Germany in 1879; the first revenue line took electric traction into use in 1881. The first electric industrial railway in Norway opened in 1892 at Skotfos Bruk near Skien. Two years later, parts of the Oslo Tramway were electrified. The first alternating current (AC) line became operational in 1892, while the first line to use a single-phase, single overhead wire power supply opened in Germany in 1903. In 1912, all German railway agreed to use the 15 kV 16 2⁄3 Hz AC standard, which was later adopted first by Sweden and then by NSB. Several of the private lines that preceded NBS's electrification chose different standards. Sydvaranger chose to install the only mainline direct current (DC) and third rail system.
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