In December 2004, Hitachi Energy received the go-ahead to proceed with the NorNed project, an HVDC transmission link with a 700 MW ±450 kV transmission capacity that connects the power grids of Norway and The Netherlands. Hitachi Energy's scope of supply included the two converter stations and the cable system for the major portion of the cable route.
The converter stations are located at the Feda substation in Norway and at the Eemshaven substation in The Netherlands.
The contract was originally awarded to Hitachi Energy in 2000, but restructuring in the power utility sector caused the project to be delayed. The contract is with the two state-owned power grid companies, TenneT in The Netherlands and Statnett in Norway. The interconnection, which is based on market coupling, has lead to power trading between the two countries and increased the reliability of electricity supply in both.
To reduce cable costs and cable losses, NorNed has two fully insulated DC cables although it is a monopolar link. This makes the current small and cable losses low, but requires a higher converter voltage.
The flexibility and speed in controlling the level and direction of the power flow provides many benefits, such as increased security of electricity supply, improved utilization of the power plants, reduced CO2 emissions and assistance in further development of renewable wind power.
Main data | |
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Commissioning year: | 2008 |
Power rating: | 700 MW |
No of poles: | 1 ( midpoint grounded in Eemshaven) |
AC Voltage: | 300 kV (Feda), 400 kV (Eemshaven) |
DC Voltage: | ± 450 kV |
Length of DC submarine cables: | 2 x 580 km |
Main reason for choosing HVDC: | Length of sea cable and non-synchronous AC systems |
Application: | Interconnecting grids |