Rail electrification in Queensland

In the late 1970s and 1980s, a significant rail electrification program was completed in the Australian state of Queensland. The electrified Queensland network is the largest in Australia with over 2,000 kilometres electrified, the next biggest is New South Wales with 640 kilometres.

Today all suburban passenger services in South East Queensland are operated by Queensland Rail electric multiple units while an extensive network of freight lines are operated to service the Central Queensland coal networks is operated by Aurizon. The two networks are joined by the electrified North Coast line from Brisbane to Rockhampton. All electrification is at 25 kV AC

In the 1980s, three significant programs were completed:

Since then there have been a number of new lines opened that have been electrified. As at 2014, 2,033 kilometes of the 7,739 Queensland network was electrified.

The first electrification proposal was in 1897 when the Chief Engineer of the Queensland Railways was sent to study electrified railways in Europe and America. At the time the technology was in its infancy, and the costs outweighed the benefits, with Brisbane having a population of just 120,000. Further studies were carried out in 1915, and three decades later more investigations were carried out.

After World War II the Brisbane suburban network had become run down, and coal shortages were affecting the ability to run regular services. A committee was appointed to investigate, delivering their report in November 1947. It recommended the electrification of the suburban network by 1959 with the 1.5 kV DC system. 290 km (180 mi) of single track including sidings would be involved, covering the lines to Shorncliffe, Yeerongpilly via Sherwood, Ferny Grove, Petrie, Pinkenba and Kingston. The report was adopted in February 1950 and preliminary works started.

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