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The Yangtze River power line crossings are overhead power lines that cross the Yangtze River in China. There are at least three power line crossings on the Yangtze River at Jiangyin, Nanjing, and Wuhu. The towers of the crossing in Jiangyin are among the highest in the world.
One exists at Jiangyin, Jiangsu Province, China. Each pylon is situated at 31°58′17″N120°3′12″E / 31.97139°N 120.05333°E and at 31°57′4″N120°2′53″E / 31.95111°N 120.04806°E . It is a section of the 500 kV power line from the Yancheng power station to the Dou Shan substation in the province of Jiangsu. The power line section running over the river has a span width of 2,303 m (7,556 ft). It is carried by two 346.5 m (1,137 ft) tall [1] suspension towers, each weighing 4,192 tonnes.[ citation needed ] (for comparison, the towers even surpass the height of the Eiffel Tower, which is 324 m (1,063 ft), including antenna). They are identical lattice towers of square cross section with an area of 68 m (223 ft) × 68 m at the base and 8 m (26 ft) × 8 m at the top. The pylons carry four conductors on the lower crossarm, 312 m (1,024 ft) above ground, with a length of 77 m (253 ft) and two conductors on the upper crossarm. The insulator strings are 10 m (33 ft) long. These pylons are both equipped with an elevator which runs in a cylindrical tube in its center. A spiral staircase circles the elevator shaft outside.
On each side of the river are each main span pylon, followed by two anchor towers; one for each circuit. The anchor pylons are each 55 m (180 ft) tall, weigh 110 tonnes and stand on an area of 16 m × 24 m (52 ft × 79 ft).
Construction of the pylons started on November 8, 2002. They were completed on April 13, 2004. On November 18, 2004, the power line went into service.
A dual circuit, 500 kV AC overhead powerline crosses the Yangtze River at Nanjing, Jiangsu Province, China, built in 1992. It uses two 257 m (843 ft) tall pylons built of reinforced concrete, which may be the tallest pylons built out of concrete in the world.[ original research? ] They are situated at 31°57′46″N118°36′58″E / 31.96278°N 118.61611°E and at 31°57′11″N118°38′4″E / 31.95306°N 118.63444°E and carry 6 conductors in two levels. The span width is 2,053 m (6,736 ft).
The HVDC Three Gorges-Changzhou powerline crosses the Yangtze River near Wuhu, Anhui Province, China, at 31°30′2″N118°22′11″E / 31.50056°N 118.36972°E and 31°30′37″N118°21′11″E / 31.51028°N 118.35306°E . The pylons were built in 2003. The crossing consists of two 229 m (751 ft) tall pylons built as constructions of tubular steel, which carry two conductors. The span width is 1,910 m (6,266 ft). Close to it, there is a 500 kV AC powerline crossing with a span width of 1,960 m (6,430 ft) on probably taller towers and a 110 kV AC powerline crossing with a span width of 1,410 m (4,626 ft). Both AC crossings have 6 conductors.
A transmission tower is a tall structure, usually a lattice tower made of steel that is used to support an overhead power line. In electrical grids, transmission towers carry high-voltage transmission lines that transport bulk electric power from generating stations to electrical substations, from which electricity is delivered to end consumers; moreover, utility poles are used to support lower-voltage sub-transmission and distribution lines that transport electricity from substations to electricity customers.
The HVDC Volgograd–Donbass is a 475 kilometres (295 mi) long bipolar ±400 kV high voltage direct current powerline used for transmitting electric power from Volga Hydroelectric Station at Volgograd in Russia to Donbas in eastern Ukraine and vice versa.
The Mettlen–Lavorgo powerline, also called the Lukmanier powerline, is the 400 kV three-phase alternating current high voltage electric power transmission line over the Lukmanier Pass in Switzerland, from Mettlen substation, next Inwil, about 7-kilometre (4.3 mi) south of Hochdorf, to Lavorgo substation, next Lavorgo, about 5-kilometre (3.1 mi) south of Faido. Trees falling on the line in 2003 caused a major blackout in Italy.
The Pylons of Messina are two free-standing steel towers, the Sicilian one in Torre Faro and the Calabrian one in Villa San Giovanni. They were used from 1955 to 1994 to carry a 220 kilovolt power line across the Strait of Messina, between the Scilla substation in Calabria on the Italian mainland at 38°14′42″N15°40′59″E and the Messina-Santo substation in Sicily at 38°15′57″N15°39′04″E.
The Pylons of Cádiz, also known as the Towers of Cádiz, are two 158 m (518 ft)-tall pylons supporting a double-circuit 132 kV three-phase AC powerline over the bay of Cádiz, Spain, running from Puerto Real Substation to the substation of the former Cádiz Thermal Power Station, situated on the peninsula upon which the city of Cádiz stands.
An overhead line crossing is the crossing of an obstacle—such as a traffic route, a river, a valley or a strait—by an overhead power line. The style of crossing depends on the local conditions and regulations at the time the power line is constructed. Overhead line crossings can sometimes require extensive construction and can also have operational issues. In such cases, those in charge of construction should consider whether a crossing of the obstacle would be better accomplished by an underground or submarine cable.
An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy along large distances. It consists of one or more conductors suspended by towers or poles. Since most of the insulation is provided by air, overhead power lines are generally the lowest-cost method of power transmission for large quantities of electric energy.
The Suez Canal overhead powerline crossing is a major electrical power line built across the Suez Canal in 1998, located near Suez, Egypt. It is designed for two 500 kV circuits.
The Kerinchi Pylon is a lattice-steel transmission tower located near Menara Telekom in Kerinchi, Kuala Lumpur, Malaysia.
Kootenay Lake Crossing is a powerline crossing of Kootenay Lake, British Columbia, Canada. The idea was to transport electricity from the Hydro dam on the Kootenay River at Brilliant to the Cominco Sullivan Mine at Kimberley. The most direct route was across Kootenay Lake. Originally it was with a span width of 3,248 metres (10,656 ft) the longest powerline span of North America and fixed on three - for each conductor a single one - 19 metres tall towers at the west shore and a 112 metres (367 ft) tall electricity pylon on the east shore. This tower was erected in spite of high mountains on the east shore for building short towers were available, as erecting span terminal towers on them would have required a longer span, for which the use of spliced conductors were required, which was undesired as the splicing point is a potential point of failure. Roebling cable provided the steel support cable for the conductor. The height of conductor over Kootenay Lake was 37 metres (121 ft).
The 400 kV Thames Crossing is an overhead power line crossing of the River Thames, between Botany Marshes in Swanscombe, Kent, and West Thurrock, Essex, England. Its towers are the tallest electricity pylons in the UK.
Aust Severn Powerline Crossing is the longest overhead power line span in the United Kingdom with a length of 1,618 m (5,308 ft).
In Poland, there are 6 powerline crossings of the Vistula river and one powerline crossing of the Odra river using pylons taller than 100 metres.
The Chūshi Powerline Crossing is a part of the Chūshi mainline, a 220 kV powerline in Japan. It has two circuits running over the Inland Sea from Takehara. It was built in 1962 and consists of two towers, each 226 metres tall, one situated in Takehara, Honshū at 34°19′55.8″N132°59′3.3″E, the other on the island of Ōkunoshima at 34°18′42.8″N132°59′32.2″E. These towers are the tallest electricity pylons in Japan and carry six conductors arranged in three levels. The span between the two towers has a length of 2,357 metres and has a minimum clearance of 42 metres. The conductors have a cross section of 170 mm2, a diameter 35.2 mm and are designed for a maximum current of 645 A.
The 275 kV Forth Crossing is an overhead power line crossing of the River Forth in Scotland. The crossing, located next to the Clackmannanshire Bridge and the Kincardine Bridge, has the tallest electricity towers (pylons) in Scotland.
The Zaporizhzhia Pylon Triple is a set of two triples of 74.5 metres (244 ft) tall electricity pylons extending over the Dnieper river standing on a 27m rock in Zaporizhzhia, Ukraine. They are used for the transport of electricity generated at the Dnieper Hydroelectric Station over a span of 900 metres from Khortytsia island to the east bank of the Dnieper. The two triples are an unofficial landmark of Zaporizhzhia.
The Jiangyin Yangtze River Bridge is a suspension bridge over the Yangtze River in Jiangsu, China. The bridge has a main span of 1,385 metres (4,544 ft) connects Jiangyin south of the river to Jingjiang to the north. When the bridge was completed in 1999, it was the fourth longest suspension bridge span in the world and the longest in China. Several longer bridges have since been completed in China and abroad, and it is currently the 15th longest suspension bridge in the world. The bridge was also the furthest downstream on the Yangtze until the completion of the Sutong Yangtze River Bridge in 2008 and the Chongming–Qidong Yangtze River Bridge in 2011.
The Osaki Channel Crossing is a power line crossing over Seto Inland Sea south of Yoshina, Takehara in Japan, which was built in 1997 and runs from Chugoku Electric Power's Ozaki Power Station at 34°15′26.4″N132°52′25.1″E to the Japanese Mainland at 34°18′19.6″N132°52′29.1″E, with two water crossings: the Nagashima Sector, connecting the Power Station to Usujima, with a span width of 1603 metres, and the Yoshina Sector, which spans from Usujima to the mainland at 2145 metres long. At a height of 223 metres, the towers of the Yoshina Sector are just 3 metres shorter than those of the Chūshi Powerline Crossing, making them the second-tallest electricity pylons in Japan. The pylons follow a barrel design with 3 crossbars.
The Zhoushan Island Overhead Powerline Tie is a 220 kV three-phase AC interconnection of the power grid of Zhoushan Island with that of the Chinese mainland. It runs over several islands and consists of several long distance spans, the longest with a length of 2.7 kilometres (1.7 mi) south of Damao Island. This span uses two 370-metre-tall (1,210 ft) pylons, which were the highest electricity pylons in the world, until 500kV line to Zhoushan from mainland was completed. The north tower on Damao Island was completed in 2009, and the south tower on Liangmao Island was completed in 2010. These pylons resemble those of the Messina Strait, but are steel-tube lattice structures.
Powerline river crossings comprise both overhead lines and cable tunnels beneath rivers and estuaries. Overhead power lines are supported on towers which are usually significantly taller than overland pylons and are more widely spaced to cross the river in a single span. Tall pylons ensure that the electricity cables which they support provide an adequate safety clearance for river traffic.
