A contract for a feasibility study into the first-ever high-voltage direct current (HVDC) offshore wind substation in China has been announced.
China has committed heavily to developing its offshore wind power generating capacity. It currently plans to have 5 GW of offshore wind power installed by 2020 and in 2017 alone it installed almost 1.2 GW of offshore wind capacity. This brought the cumulative total installed capacity to nearly 2.8 GW, third globally behind the United Kingdom and Germany.
However, the country is now faced by the challenge that all the promising wind farm sites within 10 km of the shore have already been exploited. To boost capacity further and meet the 2020 target, China is having to explore locations that are further offshore. To this end, Huadong Engineering Corporation is planning a ground-breaking 1.1 GW offshore windfarm some 90 km off the coast of Jiangsu Province in eastern China.
To support the realization of this pioneering project, Huadong has contracted DNV GL to supply technical trainings, advices and support on their feasibility study on aspects of conceptual design and risk assessment.
Traditional submarine high-voltage alternating current (HVAC) cables become extremely inefficient when transporting large amounts of electricity over such long distances. In contrast, high-voltage direct current systems allow power to be transmitted over large distances under the sea with minimal losses. Hence a key stage in the new project will be the creation of an offshore HVDC transmission system to export offshore power from the windfarm to the mainland, including offshore HVDC converter station, submarine cables and onshore HVDC converter station. This will be the first offshore Voltage-Source Converter HVDC system in China.
Haifeng Qi, President, Power China Huadong Engineering Corporation Limited Renewable Energy Corporation said this type of system is new for the Asia Pacific region, so it is invaluable to be able to work with DNV GL who has experience in both HVDC technology and offshore engineering.
“Their experience in these areas will be a critical factor in successfully delivering a major new windfarm so far from land to help China continue to lead the way in offshore wind generation.”
William Pan, Head of Offshore Wind APAC, DNV GL – Energy said that offshore wind HVDC has unique specification and requires to combine both offshore wind and HVDC technology on the limited space, to satisfy safety and function requirement. He also said he is pleased to be part of the acceleration of the local offshore wind industry development.