Offshore Wind
Tokyo Electric Power Company Renewable Power (TEPCO RP) has begun the environmental impact assessment (EIA) process for a planned 420 MW offshore wind farm off Choshi in Chiba Prefecture.
The project is one of several included in Japan’s first fixed-bottom offshore wind auction round, originally secured by a consortium led by Mitsubishi.
TEPCO RP submitted the project’s planning-stage environmental consideration document on 20 August, and Chiba Prefecture began the public consultation the following day. The consultation will run until 25 September.
According to the document, the proposed offshore wind farm would use fixed-bottom turbines across an area of approximately 4,000 hectares.
TEPCO RP is considering turbines with a rating of between 15 MW and 20 MW, with a maximum of 27 units, which would give the project a total capacity of 420 MW. The project area is located off the coast of Choshi, with parts of the relevant environmental assessment area also covering Asahi.
Construction is planned to begin in 2031 or later, with the wind farm expected to start operating in 2032 or later. This schedule is subject to subsequent project development and permitting stages.
TEPCO previously competed with Ørsted for the Choshi area, but lost the 2021 auction to the Mitsubishi Corporation-led consortium. This consortium was selected to develop a 390.6 MW offshore wind farm off Choshi, as well as two projects in Akita Prefecture.
However, in August 2025, Mitsubishi announced that it would not proceed with the three wind farms following a review of the projects’ business plans ‘due to material changes in the macroeconomic environment’.
