Nexans breaks ground with world’s first 525 kV cable innovation
Innovation
10 October 2023
3 min
Nexans Calais, France

As a world’ first, Nexans successfully achieved electrical Type Test for 525 kV DC SF6 gas free cable terminations. This allows us to offer a safer and sustainable solution to connect HVDC cables and brings us closer to our goal to electrify the future.

As the importance of electricity continues to grow, the demand for High Voltage Direct Current (HVDC) connections is increasing, for both offshore and onshore applications, coupled with the need for decarbonized electric grids. This requires the development of new robust power network solutions.

Sustainable power solutions in HVDC technology

Targeting products with lower CO2 equivalent emission potential, Nexans leveraged an extensive and in-depth knowledge to develop a full 525 kV HVDC cable system with SF6-free accessories including a dry-type Gas Insulated Switchgear (GIS) cable sealing end, and g3 gas filled GIS cable sealing end and an Outdoor Composite (or Air-Insulated Switchgear – AIS) cable sealing end.

The electrical type test according to international standards (CIGRE TB 852 and IEC 62895) was accomplished in Nexans’ High Voltage laboratory in Calais (France), under the certification of an independent third-party. The successful testing performed so far is an important step towards showing that SF6 free HVDC accessories is technically achievable and places Nexans at the forefront in the development of innovative and advanced technological solutions for the power grids, and in particularly at this voltage level of HVDC application.

To eliminate the use of SF6 in high voltage cable systems will be a significant contributor in our strive to reduce the environmental impact. We are proud to have achieved this important milestone to this.

Bjørn Sanden

VP Engineering and R&D for Transmission & Distribution Business Group, Nexans

Advantages of SF6-free high voltage accessories

The main benefits of using SF6 free high voltage accessories include a reduced environmental impact, lower maintenance requirements, and improved reliability. By eliminating the use of SF6 gas, cable terminations can reduce their potential greenhouse gas emission by 99% or more and will contribute to a more sustainable power grid.

This technological breakthrough signifies Nexans’ commitment to innovation and sustainability as it reinforces our position as a strong contributor into electrification.

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