A new high-voltage pylon has been developed by Dutch electricity transmission operator TenneT. Known as the Wintrack, the conception of the pylon was put in place to improve the effectiveness of new constructions and to reduce the amount of space that pylons consume.
Wintrack is an innovative pylon that offers minimalist design, by replacing the existing lattice tower with two smooth poles for a slimmer and more efficient design. The pylons have been shaped to offer a more aesthetically pleasing look to the Dutch landscape. They are slender and grey in appearance, so that their colour matches the skyline of TenneT’s home in the Netherlands.
The Wintrack pylon consists of a bi-pole, which is a pair of pylons, with wire bundles held one above the next. The high-voltage wire bundles are kept closely together to reduce the intensity of the magnetic field. Traditionally this is generated through the route of the high-voltage connection in lattice towers. The bundles reduce the ‘magnetic field zone’ in Wintrack pylons by over 60 percent; which is far below the magnetic fields of traditional lattice pylons, where the conductors hang next to each other.
This smaller magnetic field is produced as a result of two 380-kV circuits being placed close together within two separate pylons. This means that new electricity connections can be constructed without any major disruption to the landscape. This is also beneficial to residents of an area where a Wintrack pylon is to be constructed, as the pylons are designed so that the space around the high-voltage lines can be used more effectively, to encourage the construction of new developments within the vicinity.
In 2005 Dutch Ministry of Housing, Spatial Planning and the Environment introduced strict guidelines for any extensions of high-voltage lines, to help minimise long-term exposure of magnetic fields to humans. It was a precautionary policy, but one which TenneT followed to ensure that the limit value of 0.4 microTesla was not exceeded.
Whereas previous guidelines issued by the Ministry stated that construction of any development was restricted to a strip of land around 300 metres behind high-voltage lines, the Wintrack reduces this restriction to less than 100 metres. This helps to cut the problem of not being able to construct schools and homes unless they are behind the 300 metre mark.
The diameter of the Wintrack pylons ranges from 2.4m on the underside to 0.5m at a height of 57m; with two tubular sections per pylon. The weight of the bottommost tubular section is 40 t, with the topmost at 13 t and the length of each tubular section is 28.5 m. At its tallest the Wintrack pylon is 65m tall and is made from steel (S355). Its design has the option of combining multiple electricity connections on one pylon.
The first test of the Wintrack pylon was overseen by TenneT and the research agency KEMA back in 2008. It passed the short-circuit test, by being subjected to a huge surge current of 50 kA for 0.5 seconds. The short-circuit test saw the pylon subjected to increasingly high current intensities until 50kA was reached for 0.5 seconds, to peak at 125 kA. A noise nuisance test followed in 2009, with the first installation of three Wintrack pylons taking place in Bleiswijk, in the west of the Netherlands in 2010.
The pylons were constructed along the A12 motorway, from The Hague to Gouda, and were the construction of Volker Wessels Telecom Network Solutions, who won the contract due to their minimalist look of the pylons. The Wintrack pylons were designed by Zwarts & Jansma Architects, collaborating with KEMA.
The foundations of the Wintrack pylon were constructed by European constructor Heijmans and made use of a reinforced concrete slab. For each pylon built on a vibration-free installed pile construction, there is also a reinforced concrete dump which is produced using a higher quality of concrete to bear the load.
TenneT has plans for the new pylons to be used within infrastructural projects across the Netherlands on a much larger scale; with over 450 km of new high-voltage lines constructed across the country in the foreseeable future.
TenneT is the premier electricity transmission operator across the whole of the Netherlands and parts of Germany; with approximately 20,000 kilometres of high voltage lines. In 2008 it took over connections to the high-voltage grid and in 2010 it acquired E.ON’s German high-voltage grid. It was formerly responsible for administrating high-voltage levels of 220 kV or higher, however it currently manages the 110 kV, 150 kV, 220 kV and the 380kV grid, as appointed by the Transmission System Operator by the Office of Energy Regulation.
Through projects in the East, West and South of the Netherlands TenneT continually work to improve the high-voltage grid. The company works around the clock so that there is always an uninterrupted and continuous supply of electricity to its 35 million end users. It ranks within the top five gird operators in Europe. TenneT understands the needs of its customers, so that whenever they need electricity there will always be a reliable supply.
TenneT is also responsible for maintaining and investing in the transmission grid, whilst making sure that the grid is of 100kV or higher. It must ensure that all electricity transmissions take place as intended throughout the Netherlands and that it contributes to an integrated electricity market in Central Western Europe.
Amongst its customers TenneT includes grid operators, electricity producers, consumers and Programme-Responsible Parties. TenneT considers itself as the connecting piece between producers and consumers, which includes constant communication between the community. The company sees this as a vital necessity for its development.
Not only does TenneT monitor the reliability of the transmission grid, but the company also strives to be at the forefront of technological developments. It also always aims to anticipate the change in society’s need for electricity transmission.
This is achieved via a comfortable balance between managing a reliable electricity supply and its social responsibilities as grid administrator. It does this by providing services that support the development of sustainable energy supplies and by supporting free-marketing operations.
TenneT is an independent TSO, with a responsibility to people, society and the environment, with quality and integrity at the heart of its corporate key elements. It understands that by adhering to proper market operations and by continuing to supply electricity in the most reliable way, it is a valuable asset to improving social and economic developments.
All attempts are made to limit the effects that its operations have on the planet, by keeping track of its CO2 footprint in order to prevent unnecessary air emissions, where possible.
Moving forward TenneT is working towards the acquisition of a more prominent position among TSOs in Western Europe when it comes to its corporate social responsibility. The use of the Wintrack pylon is just one of the ways that it is doing this.