One-step-installation of offshore wind turbine on large-scale bucket-top-bearing bucket foundation

Abstract

In 2010, the first offshore wind turbine with integrated installation was established in Qidong sea area of Jiangsu Province, China, which led to the implementation phase of one-step-installation technique based on the design and construction of large-scale bucket-top-bearing (LSBTB) bucket foundation. The critical technique of LSBTB bucket foundation included self-floating towing, penetration with adjustment of horizontal levelness, removability and one-step-installation. The process of one-step-installation included the prefabrication of LSBTB bucket foundation in onshore construction base, installation and debugging of wind power, overall water transportation of foundation and wind power system, and installation of foundation and offshore wind turbine on the appointed sea area. The cost of one-step-installation technique was about 5 000 Yuan/kW, which was 30%-50% lower than that of the existing technique. The prefabrication of LSBTB bucket foundation took about two months. During the one-step-installation process, the installation and debugging of wind power and overall water transportation need about one to two days in sea area within 35 m depth. After the proposed technique is industrialized, the cost will be further reduced, and the installation capacity is expected to be up to 500 wind turbines per year.

Keywords

one-step-installation technique / large-scale bucket-top-bearing bucket foundation / self-floating towing / penetration technique with adjustment of horizontal levelness / removability technique / construction and installation cost

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