A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems.
NorNed is a 580-kilometre (360 mi) long high-voltage direct current submarine power cable between Feda in Norway and the seaport of Eemshaven in the Netherlands, which interconnects both countries' electrical grids. It was once the longest submarine power cable in the world. Budgeted at €550 million, and completed at a cost of €600m, the NorNed cable is a bipolar HVDC link with a voltage of ±450 kV and a capacity of 700 MW. NorNed is a joint project of the Norwegian transmission system operator Statnett and its Dutch counterpart TenneT. The cable system itself and the two converter stations were produced by ABB.
Aibel is a service company within the oil, gas and offshore wind industries. The company provides engineering, construction, modifications and maintenance through a project's life cycle.
Gode Wind 1, 2, and 3 are offshore wind farms located north-west of Norderney in the German sector of North Sea. They are owned by Ørsted. Gode Wind 1 and 2 are operational, while Gode Wind 3 is being developed.
HVDC BorWin1 is the first HVDC facility in the world to be built for importing power from an offshore wind park to shore, and the first to use voltage source converters (VSC) in Germany. It connects the offshore wind park BARD Offshore 1 and other offshore wind farms in Germany near Borkum to the European power grid. The facility was built by ABB and has a capacity of 400 MW at a bipolar voltage of ±150 kV. HVDC BorWin1, which leads from BorWin Alpha Offshore Platform to Diele substation, consists of a 75 kilometres (47 mi) of underground and 125 kilometres (78 mi) of submarine cable.
BritNed is a 1,000 MW high-voltage direct-current (HVDC) submarine power cable between the Isle of Grain in Kent, the United Kingdom; and Maasvlakte in Rotterdam, the Netherlands.
Nordsee-Ost offshore wind farm is an offshore wind farm in operation in the eastern part of the North Sea German sector. The project was developed by RWE Innogy, a subsidiary of RWE.
The North Sea Link is a 1,400 MW high-voltage direct current submarine power cable between Norway and the United Kingdom.
HVDC DolWin1 is a high voltage direct current link built to transmit offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters are used and the total cable length is 165 km. The project was built by ABB and was handed over to its owner, TenneT, in July 2015, the fifth such project to be completed in Germany in 2015.
HVDC HelWin1 is a high voltage direct current (HVDC) link built to transmit Offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters are used and the total cable length is 130 km. The project was completed and handed over to its owner, TenneT, in February 2015.
The Johan Sverdrup oil field is an oil field in the North Sea, about 140 kilometres (87 mi) west of Stavanger, Norway. The field lies in two different production licenses and consists of two different discoveries called Avaldsnes and Aldous Major South. When it was revealed that these discoveries constituted one single field, it was renamed Johan Sverdrup after the father of Norwegian parliamentarism. The field has not yet been unitized between production licenses 501, 501B, and 265. Johan Sverdrup is expected to hold 1.9–3.0 billion barrels of oil. According to Statoil, the field is in 110 to 120 metres water depth, and the reservoir is at 1900 meters depth.
HVDC BorWin2 is a high voltage direct current (HVDC) link built to transmit offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters are used and the total cable length is 200 km. The project was completed by the Siemens/ Prysmian consortium and handed over to its owner, TenneT, in January 2015, becoming the first such project to be completed.
HVDC HelWin2 is a high voltage direct current (HVDC) link built to transmit offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters with DC ratings of 690 MW, ±320 kV are used and the total cable length is 130 km. The project was built by the Siemens/Prysmian consortium with the offshore platform built by Heerema in Zwijndrecht, Netherlands. The topside measures 98 m x 42 m x 28 m and weighs 10200 tonnes. The project was handed over to its owner, TenneT, in June 2015, the fourth such project to be completed in 2015.
HVDC SylWin1 is a high voltage direct current (HVDC) link to transmit offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters with DC ratings of 864 MW, ±320 kV are used and the total cable length is 205 km. The project is similar to the HVDC BorWin2 project but has slightly higher power and voltage ratings. It is being built by the Siemens/ Prysmian consortium and was handed over to its owner, TenneT, in April 2015.
HVDC DolWin3 is a high voltage direct current (HVDC) link to transmit Offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters with DC ratings of 900 MW, ±320 kV are used and the total cable length is 160 km.
HVDC BorWin3 is a high voltage direct current (HVDC) link under construction to transmit offshore wind power to the power grid of the German mainland. The project differs from most HVDC systems in that one of the two converter stations is built on a platform in the sea. Voltage-Sourced Converters with DC ratings of 900 MW, ±320 kV are used and the total cable length is 160 km. The project is the most recent of the German offshore HVDC projects to be awarded. It is being built by the Siemens/ Petrofac consortium with the offshore platform contract awarded to Drydocks World in Dubai. The project is expected to be handed over to its owner, TenneT, in 2019. The project started power transmission in August 2019. TenneT took control of operations in February 2020.
Adelanto Converter Station in Adelanto, California, is the southern terminus of the 2,400 MW Path 27 Utah–California high voltage DC power (HVDC) transmission line. The station contains redundant thyristor-based HVDC converters rated for 1,200 MW continuous or 1,600 MW short term overload. The 300-acre (120 ha) station was completed in July, 1986 at a cost of US$131 million. The northern terminus of Path 27 is fossil fueled Intermountain Power Plant in Utah.
Kriegers Flak is a 605 MW offshore wind farm in the Baltic Sea on the Danish part of the reef of the same name. It forms part of a new 400 MW interconnector between Denmark and Germany.
Veja Mate is a German 402 MW offshore wind farm in the German Bight of the North Sea about 95 km northwest of Borkum. The wind farm consists of 67 Siemens Wind Power SWT-6.0-154 turbines, each with a 6 MW capacity.
