SEP Dafeng Offshore Wind Power Project Connected to Grid with Full Capacity
At 9:16 p.m. on December 20, 2018, all the 72 wind turbines of SEP Dafeng H3# Offshore Wind Power Project were connected to the grid following the successful synchronization of No. 57 wind turbine, marking that the project realized grid connection with full capacity smoothly and that SEP gained major breakthrough in implementing "Two Sea-related" (overseas and offshore wind power) strategy. The project started construction on March 22, 2018, and completed all related hoisting work by December 19, which set a new record in the construction speed of same-scale offshore wind power project in the domestic electricity industry, achieving the goal of commencement, completion and profit making in the same year.
Located in the waters north of Liangyuesha sandbar, Dafeng district, Yancheng, Jiangsu province, the project is an offshore wind farm with the longest offshore distance in China at present (the center of the wind farm has an offshore distance of 43 km), covering a total sea area of 90 square km, and has installed 72 units of 4.2 MW wind turbines altogether, with a total installed capacity of 302.4 MW and estimated annual power generation of 850 GWh.
Starting with in-depth design optimization, the project adopted digital technology to develop and apply a large quantity of advanced offshore wind power new technologies, new materials and new processes. Britain-based Atkins, a world-leading design and engineering consultancy, was invited to optimize the design of the 220kV offshore booster station, the key part of the offshore wind farm, in order to ensure that the project would reach world-leading level as a whole. The construction of the booster station first introduced China Classification Society (CCS) in inspection and consulting services, and became the first domestic offshore booster station to obtain the Certificate of Offshore Wind Farm Facility Compliance issued by CCS. Moreover, the project chose double-circuit 220kV three-core submarine cables, with the single submarine cable 52.5 km in length and 5400 tons in total weight, which is the longest three-core submarine cable without intermediate hard joint put into operation in China so far.
Since construction began, the project team overcame a series of unfavorable factors such as short construction period and frequent occurrence of typhoon, conquered various difficulties including complicated and severe construction conditions in the related sea area, pile-sliding phenomenon which frequently happened to marine pile foundations, long distance laying of high voltage submarine cable during the typhoon season and tight supply chain of tower barrels and wind turbines, optimized construction processes and sequences repeatedly, intensified four major engineering controls, carried out synchronous crossover work of cable laying and wind turbine hoisting, enhanced wind turbine defect elimination, power transmission and grid connection organization capability, and thus guaranteed commercial operation with full capacity and high quality during extremely limited marine operation window.
The successful commercial operation of the project is an important measure by SEP to complete the implementation of SPIC strategy in the new era, which will inject new energy for the group company to build core competitiveness in offshore wind power, and also help its offshore wind power business ascend to the first echelon in the industry and finally reach the world-class level.
Invested and constructed by SEP Dafeng Offshore Wind Power Co., Ltd. under the flag of SPIC, the project was entrusted to Jiangsu Offshore Wind Power Generation Co., Ltd. for engineering management, with Huadong Engineering Corporation Limited under Power China taking charging of designing, Shanghai Dong Hua Construction Management Co., Ltd. responsible for supervision and Huadian Heavy Industries Co., Ltd. as the "six in one" EPC contractor, and adopted 4.2 MW offshore smart wind turbine generators developed by Chinese wind turbine manufacturer Envision Energy.