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Electricity Ashburton Limited, trading as EA Networks is a co-operatively-owned electricity distribution company, based in Ashburton, New Zealand. The company was formed as Electricity Ashburton in 1995 after a reorganisation of the Ashburton Electric Power Board into a commercial company. It adopted its current trading name EA Networks in late 2012. It is unique among New Zealand electricity distribution companies in that it is the only company that is a cooperative, whereby shares in the company are owned by electricity consumers connected to its network. EA Networks owns and operates the subtransmission and distribution network in the Ashburton District (also known as Mid-Canterbury) in the South Island. Outside the Ashburton township (pop. 17,700), most of the district is rural with a high usage of irrigation, with the associated water pumps responsible for more than 85 percent of EA Networks' peak summer demand. EA Networks also owns a fibre optic cable network interconnecting its zone substations, which also offers broadband internet services to customers along the cable network. It also in a joint venture with Barrhill Chertsey Irrigation regarding an irrigation project covering of farmland in the north-eastern Ashburton district.〔(【引用サイトリンク】title= About - Electricity Ashburton )〕 ==History== Reticulated electricity first arrived in Ashburton in 1908, when private company Craddock & Co established a 220-volt direct current electricity network to supply Ashburton township. The electricity was supplied from a 30 kW generator driven a steam traction engine. A network of 3300-volt and 230/400-volt alternating current lines were later established to supply the township.〔 In 1923, the Ashburton Electric Power Board (AEPB) was established to operate the distribution network in the Ashburton area, taking over from the private companies and establishing a district-wide network of 6.6kV and 11kV distribution lines to replace the DC and 3.3kV lines. In 1924, the AEPB's network was connected to the national grid and Coleridge Power Station when a 110/11 kV substation was established in central Ashburton. A second connection to the national grid was later established near Methven. After the Second World War, the AEPB established a production facility and reticulation network to supply coal gas to Ashburton township, and was subsequently renamed the Ashburton Electric Power and Gas Board. The coal gas system was disestablished in 1973 when it became uneconomical and the board reverted to its original name.〔 By the early 1960s, the need for a sub-transmission network became apparent, and in 1967 the AEPB established its first 33 kV subtransmission lines and zone substations, supplied by three 11/33 kV step-up transformers at Ashburton substation. In 1971, the last 6.6 kV lines were converted to 11 kV. As irrigation loads increased and the subtransmission network was extended into the 1980s, two 110/33 kV grid connections were established at Ashburton and Cairnbrae, near Methven, to supply the network.〔 The AEPB also established a 1.8 MW hydroelectric power station at Montalto in 1982.〔(【引用サイトリンク】title= Highbank and Montalto power stations )〕 In the late 1980s and early 1990s, Transpower (then a division of the Electricity Corporation) went about a rationalisation of older transmission lines in the South Island, and as a result dismantled the 110 kV lines between Hororata and Temuka which supplied Ashburton. As a result, a new 220/33 kV grid connection was established in 1992 under the Islington/Bromley to Twizel 220 kV lines at Elgin, 7 km south-east of Ashburton township, to supply the AEPB network in the Ashburton area.〔 Also in 1992, the Fourth National Government passed the Energy Companies Act, which required electric power boards to be reformed to become commercial power companies. It was decided by the AEPB to become a cooperatively-owned company, and in 1995 became Electricity Ashburton Limited. Electricity Ashburton was subsequently responsible for subtransmission, distribution and retailing in the Ashburton District, as well as the Montalto Power Station.〔 By 1997, the huge increase in irrigation loads were putting a strain on the 33 and 11 kV lines. To alleviate the issue, Electricity Ashburton decided to convert the 33 kV subtransmission network to 66 kV, and to convert the rural 11 kV distribution network to 22 kV (the urban distribution networks in Ashburton and Methven would remain at 11 kV due to the cost of replacing a large network of underground cables). Electricity Ashburton also took the opportunity to connect the Electricity Corporation's 26 MW Highbank hydro power station to its network instead of to Transpower's national grid, and to relinquish the Cairnbrae grid exit point and connect its entire network through the grid exit point at Elgin.〔 In 1998, the Fourth National Government reformed the electricity sector, requiring electricity companies to split their lines and supply businesses and to sell off one of them. As a result, Electricity Ashburton decided to concentrate on the distribution business, and sold its retail base and the Montalto power station to Tauranga-based generator-retailer TrustPower in April 1999. As of April 2012, Electricity Ashburton has converted the majority of its sub-transmission network to 66 kV, and has converted a significant portion of its rural distribution network to 22 kV. It plans to convert the last sub-transmission line to 66 kV by 2019.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Electricity Ashburton」の詳細全文を読む スポンサード リンク
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