Japan lists 17 offshore wind Preparation Zones, sea areas where a prefecture has begun talks with local stakeholders. They carry no tender and no right to use the sea. The list looks uniform, but state surveys reach only five zones we could confirm, and developer environmental filings cluster in a few.
Akita City and Hibikinada were Preparation Zones in June 2025 and Promising Zones by October. Three new areas joined on the same day, so a place on the list says little about waiting time.
Three announcements since June 2025 show 18 proposals or requests and seven areas selected. Five of those seven are Preparation Zones today, and survey data shapes how developers prepare for a tender.
Across the 11 zones named as floating, we can tie only one environmental filing to a specific zone, in Wakayama. Five of the other six zones have filings.
👉 Background: Japan’s offshore wind policy framework
Where Preparation Zones sit in Japan’s three stages
The statute covers Promotion Zones, the areas open to a developer tender. The two earlier stages are set by government guidelines under the Marine Renewable Energy Act, renamed in April 2026.
| Stage | Condition | Zones |
|---|---|---|
| Promotion | Designated by the state under statutory criteria, with a tender to select a developer | 12 |
| Promising | A candidate site, stakeholder consent to a statutory council (where the state, prefecture and fishers negotiate) and a likely fit with the criteria | 9 |
| Preparation | Short of those conditions, but the prefecture has started stakeholder talks with a council in mind | 17 |
The listing itself means less than it appears to. A prefecture weighs the views of the fishing groups involved and decides whether it can go public, then the state makes the call. No developer, price or schedule exists at this stage.
The listing does open a door in practice. Preparation Zones can receive site surveys by JOGMEC, the state energy and minerals agency. They can also receive a preliminary grid study and a state marine environment survey. The guidelines encourage prefectures to come forward early with this stage in view.
The 17 zones and how differently they are moving
The latest review we can confirm is dated 3 October 2025, and we found no newer one as of 7 November 2026. The survey and assessment columns show how far the zones differ. Locations are on the Japan offshore wind project map.
| Zone | Type | JOGMEC survey | Developer filings |
|---|---|---|---|
| Hokkaido Iwau-Minamishiribeshi (floating) | Floating | None | None found |
| Hokkaido Shimamaki (floating) | Floating | None | 5 off Shimamaki (cannot be separated from the fixed-bottom Promising Zone) |
| Aomori Mutsu Bay | Fixed-bottom assumed | None | 2 |
| Iwate Kuji (floating) | Floating | None | None found |
| Chiba Asahi | Fixed-bottom assumed | Selected Oct 2025 | None found |
| Tokyo Oshima (floating) | Floating | None (developers began a joint survey) | None found |
| Tokyo Niijima (floating) | Floating | Selected Jun 2025 | None found |
| Tokyo Kozushima (floating) | Floating | Selected Jun 2025 | None found |
| Tokyo Miyake (floating) | Floating | None | None found |
| Tokyo Hachijo (floating) | Floating | None | None found |
| Toyama East (floating) | Floating | None | None found |
| Fukui Awara | Fixed-bottom assumed | None | 3 |
| Wakayama (east) | Fixed-bottom assumed | Selected Oct 2026 | 1 |
| Wakayama (west, floating) | Floating | None | 1 (2019) |
| Saga Karatsu | Fixed-bottom assumed | None | 6 (plus 2 withdrawn) |
| Nagasaki Goto South (floating) | Floating | None | None found |
| Kagoshima Ichikikushikino | Fixed-bottom assumed | Selected Oct 2026 | 2 |
Three months in 2025: two zones moved up, three joined
The list reads like a queue, yet it turned over quickly. Akita City and Hibikinada appeared as Preparation Zones on 26 June 2025 and as Promising Zones on 3 October. Asahi, Goto South and Ichikikushikino joined on that same date, taking the total from 16 to 17.
The stage above moved too. Hiyama and Matsumae in Hokkaido were Promising Zones in June and sit under Promotion Zones in the October list. Iwau-Minamishiribeshi and Shimamaki are split: the fixed-bottom parts are Promising Zones and the floating parts remain in Preparation.
The guidelines do not require an area to pass through this stage first. Local consent and the likely fit with the criteria set the pace, so the date of listing cannot be used to count down to a tender.
18 survey proposals, seven areas selected
JOGMEC surveys wind, seabed and metocean conditions under Japan’s “central method”, in which the state does the early site work. Results go to the developers joining the tender, and those developers are not expected to survey the site themselves first. That changes a real spending decision for anyone tracking a zone.
Coverage is limited. Three government announcements show 18 prefectural proposals or requests in total, and seven areas selected:
- June 2025: two of five (Niijima, Kozushima)
- October 2025: three of eight (Akita City, Asahi, Hibikinada)
- October 2026: two of five (Wakayama east, Ichikikushikino)
The 18 may count repeat requests and requests for Promising Zones, and selections from fiscal 2023 and 2024 are outside this count. On this basis, five of the 17 Preparation Zones are covered.
The government states each time that the survey does not lead to designation, so selection is no promise. Nor is the work certain to run smoothly. Asahi lies about 10 km from shore in roughly 20 m of water. On 20 September 2026, 14 crew evacuated a survey vessel there as a typhoon approached. Nobody was hurt, and JOGMEC said it would review what happened.
11 floating zones, one identifiable filing
A developer may file the first document of an environmental assessment, which covers siting and scale at an early stage, well before any tender. The number of filings gives a rough view of developer interest in an area. It gives no assurance of winning.
Set against the 17 zones, the pattern is uneven. Among the six fixed-bottom zones, only Asahi shows no filing, and Karatsu has six. Across the 11 zones named as floating, the one filing we can tie to a zone dates from 2019, in Wakayama. Shimamaki has five, but they cannot be separated from the fixed-bottom Promising Zone.
The five Tokyo zones illustrate the gap. The metropolitan government is aiming for gigawatt-scale floating wind, developers have begun a joint survey off Oshima, and Niijima and Kozushima have state surveys ahead. A search of the national database by name still finds no filing for any of them. The same holds for Goto South, in the same city as the 16.8 MW Goto project that began operating on 5 January 2026.
For the technology and market background, see 👉 Floating Offshore Wind in Japan.
A lender needs revenue terms, measured wind and seabed data, and a view of the grid connection. None of these is settled in a Preparation Zone. Revenue waits for the tender, and grid work is at most at the preliminary study stage. We would therefore expect spending at this stage to come from developers’ own funds, with no project debt. Whether JOGMEC covers a zone is one of the few firm facts that changes that burden.
Read this list by where local talks, state surveys and developer filings start to line up, because the zone count alone tells you little.
With 11 of 17 zones named as floating, the list can look like a measure of Japan’s future floating market. What it confirms today is narrower: prefectures have begun talking to stakeholders. Overlay the state surveys and developer filings, and the set of zones with visible momentum becomes much smaller.
Early engagement is worth considering if your project or supply plan is tied to a specific sea area. A local relationship can pay off over a long period. Exercise caution if you are treating a listing as a tender date, or counting these zones in a demand forecast. The government itself says that survey selection does not lead to designation.
The next signal is the coming zone review. In 2025 there were announcements in June and October, and the list changed within three months. Which zones advance and which ones join will say more than the total.
Frequently Asked Questions
Related DeepWind Articles
- Japan’s 12 Offshore Wind Promotion Zones: Project List and Status (2026)
- Japan’s Offshore Wind Promising Zones
- Japan’s Offshore Wind Policy Framework
- Floating Offshore Wind in Japan
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