Tohoku Electric Power Co., Inc. and BW Ideol have obtained approval in principal (AiP) from the Nippon Kaiji Kyokai (ClassNK) for the design of a floating offshore wind turbine system.
This system features a concrete barge-type floating substructure designed to accommodate a 15 MW-class wind turbine.
Tohoku Electric Power and BW Ideol have been jointly conducting feasibility studies since May 2022 with the aim of commercialising a floating offshore wind power project in offshore Kuji City, Iwate Prefecture. This AiP acquisition is part of those efforts. The floating offshore wind turbine system covered by this AiP is specifically designed to meet the environmental conditions off Kuji City and is based on BW Ideol's patented Damping Pool technology. The floating substructure is made of concrete, which is expected to suit mass production, and a hybrid mooring system using synthetic fibre rope and steel catenary chains has been selected for the mooring system.
BW Ideol had already obtained Basic Design Certification from DNV in May 2025 for its standardised barge-type floating structure designed to accommodate 15 MW-class wind turbines, which demonstrated high technical reliability based on international standards. The acquisition of this new AiP from ClassNK, a leading certification body in Japan, further confirms its suitability and reliability for both global and Japanese markets.
Moving forward, both companies will jointly advance a feasibility study off the coast of Kuji City, Iwate Prefecture, based on BW Ideol's Damping Pool technology. Through these efforts to commercialise floating offshore wind power generation, the companies will actively pursue the expansion of renewable energy adoption in Japan.
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