Published: January 31, 2025 | Updated: October 7, 2026
Offshore Yurihonjo, Akita Prefecture is a designated Promotion Zone under Japan’s Renewable Energy Sea Area Utilisation Act. A developer was selected in Round 1 of Japan’s offshore wind auctions, but that developer withdrew in August 2025 and the project has not proceeded. Neither the timing nor the terms of the re-tender have been published (as of September 2026).
This article sets out the conditions of the zone itself, the sea area, water depth, wind resource, ports and grid connection, alongside what Round 1 planned and why it stopped. Items that the re-tender will decide are marked TBD.
➡ For an overview of all ten Promotion Areas as of 2025, see:
Promotion Areas for Offshore Wind in Japan – 2025 Overview
1. Zone Profile and Re-tender Status
This area remains a designated Promotion Zone, but the developer selected in Round 1 withdrew in August 2025. Neither the timing of the re-tender nor the terms of the occupancy guidelines have been published (as of September 2026). The developer, price, equipment configuration and schedule are therefore undetermined, and the table below marks them TBD. Round 1 figures are kept as a record of what was planned before the withdrawal, not as an input to the re-tender.
| Project name | Offshore Yurihonjo, Akita Prefecture (Promotion Zone) Round 1 project name: Akita Yurihonjo Offshore Wind |
| Developer | TBD, pending the re-tender Round 1: Akita Yurihonjo Offshore Wind LLC (withdrawn) |
| Partners | TBD, pending the re-tender Round 1: Mitsubishi Corporation Offshore Wind Ltd.C-TECH CORPORATIONVenti Japan Inc.Mitsubishi Corporation (withdrew in August 2025) |
| Location | Offshore Yurihonjo City, AKITA Prefecture |
| Type | Fixed-bottom Offshore Wind Power |
| WTG | TBD Round 1 plan: GE |
| Price | TBD Round 1 awarded price: 11.99 JPY/kWh |
| Capacity | TBD Round 1 plan: 845 MW (13 MW x 65 turbines) |
| Start of Construction | TBD Round 1 plan: March 2026 (onshore), April 2029 (offshore) |
| Start of Operation | TBD Round 1 plan: December 2030 |
2. Location
2-1. Sea & Geographical Features
The sea area is approximately 13,040 ha, and the water depth is approximately 15 to 30 m. The average wind speed is high, and GE’s Haliade-X 13 MW large wind turbines will be used.
2-2. Port Infrastructure & Grid Connection
Under the Round 1 plan the project was to be based at Akita Port during construction and Honjo Port during operation and maintenance, and connected to the Tohoku Electric Power Network’s Kawabe substation.
3. Overview of Wind Turbine Facilities
4. Project Timeline & Development Phases
The Akita Yurihonjo project follows a structured 4-phase development approach:
1️⃣ Development Phase (2021-2026)
- December 2021: Public auction awarded
- Environmental impact assessment (EIA), seabed surveys, wind measurements
- Grid connection approvals & supply chain planning
- Stakeholder engagement with local fishing industries & communities
2️⃣ Construction Phase (2026-2030)
- March 2026: Onshore substation & transmission infrastructure
- April 2029: Offshore foundation & cable installation
- 2029-2030: Wind turbine assembly, installation & commissioning
3️⃣ Operation & Maintenance (2030-2052)
- GE and local partners to manage long-term O&M (Operations & Maintenance)
- Maintenance hub set at Honjo Port
4️⃣ Decommissioning & Repowering (2052 onwards)
- End-of-life planning, potential repowering with next-gen turbines
EIA status
| 事業名称 Project name | 事業者名 Developer | 手続段階 EIA Stage | 容量 Capacity | 基数 Turbines | 出力 Rating | 更新日 Last Updated |
|---|---|---|---|---|---|---|
| （仮称）秋田県由利本荘市沖における洋上風力発電事業 Akita Yurihonjo Offshore Wind | 秋田由利本荘オフショアウィンド合同会社 Akita Yurihonjo Offshore Wind LLC | 方法書 Method Statement | Up to 910MW | 65 | 12.6-14MW | 2022/12/06 |
Source: Environmental Impact Assessment Case Information (Ministry of the Environment, Japan)
5. Local Coordination Status
A legally mandated council has already been established. Coordination with local fishery stakeholders is ongoing, and a six-year fisheries impact assessment is planned from pre-construction to post-operation. It has been agreed that 0.5% of electricity sales revenue will be contributed to a fund for regional benefit.
6. Reviewing the Business Plan from Scratch?
Mitsubishi Corporation announced that it had recorded an impairment loss of 52.2 billion yen for the April–December 2024 period due to a reassessment of its three domestic offshore wind projects. At a press conference, President Katsuya Nakanishi stated, “We take the impairment seriously” and indicated that the company will reconsider its future business policy from scratch.
6-1. Causes of the Impairment and Future Policy
Mitsubishi Corporation won bids for three projects in 2021 and has been developing them for about three years. However, due to global inflation, yen depreciation, and rising interest rates, project costs significantly exceeded expectations. As a result, the company is reassessing profitability, with a final decision on whether to continue the projects to be made in the future.
The company also explained that nearly all recorded assets have been written off, and although further impairment losses may occur, the impact would be limited.
6-2. Breakdown of the Impairment Loss
Expenses related to surveys, design, and permitting had been recorded as assets but are now entirely written off. The total of already-paid expenses and expected future costs amounts to 52.2 billion yen.
6-3. About the Bid Pricing
In the 2021 auction, Mitsubishi Corporation won the projects with significantly lower bids than its competitors. The company explained that the decision was based on risk analysis using the expertise of Eneco. However, higher-than-expected inflation and cost increases greatly impacted the projects’ profitability.
6-4. Future of the Offshore Wind Business
Mitsubishi Corporation recognizes offshore wind as a key power source for a decarbonized society. Going forward, it intends to carefully assess its business strategy in light of inflation, interest rates, and currency trends.
7. Mitsubishi-led Consortium to Exit Three Offshore Wind Projects in Japan-Aug 26th
Mitsubishi Corporation and partners withdrew from offshore wind projects across three sites off Chiba and Akita prefectures in August 2025.
7-1. Why Exit?
- Ultra-low bid prices during the auction
- Rising material and construction costs
- Projects deemed no longer economically viable
This marks a major setback for Japan’s flagship renewable energy program.
Re-tendering is expected, but the withdrawal highlights the challenges of balancing cost-competitive auctions with the realities of supply chain inflation and project financing.
7-2. Implications
- Japan’s offshore wind strategy may face a significant review
- Timeline pressure toward the 2030 (10 GW) and 2040 (30-45 GW) national targets increases
- Investor confidence hinges on how the government resets its renewable energy policy
8. LCOE and IRR Estimation
Evaluating the bankability of offshore wind projects requires close attention to key cost indicators such as LCOE (Levelized Cost of Energy) and IRR (Internal Rate of Return). However, in Japan’s Promotion Zones, detailed project-level cost information remains limited in publicly available materials. As a result, investors and developers often lack sufficient data to form a fully informed assessment.
To address this gap, DeepWind applies a proprietary cost model using representative site conditions for each project, including wind resource (capacity factor), water depth, distance to port, and distance to grid connection point. Based on these input parameters, we estimate CAPEX, OPEX, LCOE, and IRR in a consistent framework.
This approach allows us to provide a cross-project comparison of the relative economic positioning of Japan’s Promotion Zone projects.
▶ For the latest model assumptions and updated relative positioning, please refer to the cost analysis Pillar article below.
👉 Cost Realities of Japan’s Offshore Wind: Analyzing LCOE and IRR Across 12 Promotion Zones (Latest Edition)
What the Re-tender Has Yet to Settle
The developer selected in Round 1 withdrew in August 2025, and METI and MLIT published their analysis of why on 23 December 2025. The area remains a designated Promotion Zone, but neither the timing of the re-tender nor the terms of the occupancy guidelines have been published (as of September 2026).
The developer, the price, the equipment configuration and the operation date are therefore all undetermined. The Round 1 figures kept in this article record what was planned before the withdrawal; they do not indicate where the re-tender will land. The TBD entries above will be updated once the guidelines are issued.
The reasons for the withdrawal reach into the auction design itself. See 👉 Why Japan’s Offshore Wind Round 1 Ended in Withdrawal.
To explore how this area compares nationally and understand Japan’s offshore wind roadmap, visit:
Promotion Areas for Offshore Wind in Japan – 2025 Overview —
your guide to Japan’s offshore wind Promotion Areas.
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