Poseidon
152 km2 area. Up to 81 turbines with total height 260-340 m. Expected to produce approximately 5.5 TWh/year.
Status
Advanced Developmentlifecycle stage
ProspectiveHafrok completion outlook
Ownership
Vattenfall — 85% ◆ZVZephyr Vind — 15% ◆
Location
SwedenSkagerrak
Technology
Capacity
1,400 MW ◇
Turbines
81 ◇
Foundation
Floating ◆
Site & conditions
Site rights
Seabed rights held 2024-11 ◇
Water depth
45–201 m ≈
Distance from shore
25 km ◆
Wind speed
9.9 m/s @ 150 m ≈
Revenue & grid
Offtake
—
Grid
Not recorded ◇
Connection
Grid connection details TBD; Svenska kraftnat connection … ◇
Schedule
FID
Not taken
COD · Hafrok
2036 expected
Delivery outlook modelled by Hafrok · calibrated on delivered projects
2036
expected year of commercial operation
Chance of delivery
≈62%
estimated chance this project reaches commercial operation
Advanced Development projects complete ≈75% of the time on Hafrok's record. This one sits well below that: a market with a thinner delivery record, its size, technical complexity and no offtake contract yet.
COD outlook
If it completes, when — Hafrok’s probability by year (teal)
| Year | Probability |
|---|---|
| 2035 | 14.1% |
| 2036 (expected) | 28.0% |
| 2037 | 22.7% |
| 2038 | 14.6% |
| 2039 | 8.7% |
| 2040 | 5.1% |
| 2041 | 3.1% |
| 2042 | 1.8% |
| 2043 | 1.1% |
| 2044 | 0.7% |
How Hafrok got this date
1
Starting point: the last dated milestone
Consent granted in
2024. From there Hafrok adds how long similar projects (floating, in developing offshore-wind markets) took to reach commercial operation, measured on projects that have delivered.2
Typical timing
Starting point plus the typical remaining time gives a middle estimate of
2030; the faster quarter of similar projects would be done by 2028, the slower quarter not until 2030 Q3.3
No route to market yet — counted from 2029
The project has no offtake contract yet. No contract, auction or tariff exists in Sweden today that a project without an offtake agreement could win, and none is scheduled. Hafrok believes a first support award there is unlikely before
2029 Q3, and counts from then. This is Hafrok's judgment, not a fact on the record — what it rests on: Sweden market page. The permits are not affected; winners typically reach final investment decision about 2 years after an award (2031 Q3), then build time on top gives 2035 Q3. That is later than the milestone timing, so the auction sets the date.4
Result
Expected commercial operation
2036, likely range 2034–2037 (the middle half of outcomes for similar projects). The auction step above sets the date: the round has to be won before building can start.5
Year-by-year chart
The bars spread that estimate across years using how similar projects actually slipped against their dates — more often late than early, which is why the bars lean right.
6
Chance of delivery — separate from timing
Start from the share of Advanced Development projects that went on to complete — ≈75%, measured on Hafrok's record of delivered and abandoned projects, with an allowance held back where that record cannot yet speak (projects still unresolved, changed market conditions). Consented projects have historically completed at very high rates, but the 2023–25 downturn showed consented-but-unfinanced projects can still fail — the estimate holds back for the offtake and financing gates still ahead. Then adjust for this project's own evidence — offtake, market, size, technical complexity — to ≈62%, which rates it
Prospective on Hafrok's four-step delivery scale (Delivering · Expected · Prospective · Fragile).Project timeline verified milestones only — each date carries its provenance mark
Dashed tick marks today (9 Sep 2026).
Revenue & offtake route to market — open
No offtake secured — route to market open
The routes describe what exists in this market — not a prediction of which the project will take. Timing math for the auction gate lives in the delivery outlook above.
Installation how the build is going · from satellite counts and Hafrok’s registers
Installation not started
nothing to count yet: the satellite tracker begins when offshore construction does
Installation · on record
StageAdvanced Development
Offshore constructionnot started
Expected start of operationnot stated
Construction ports
PortGothenburg ◇·quay 13100 m · draft 20.4 m
Sources & verification
3/15 fields verified · rests on 6 sources (1 primary) · ◆ 3 documents held
◆Verified≈Modelled◇Sourced∴Inferred⌁Convention○Unverified∅No source·Derived
Numbers are stable citation ids — grouped by source class, so they are not consecutive.
Operator2
[2]
Vattenfall2022◆ Vattenfall invests in two offshore wind …
“Vattenfall will hold an 85% ownership stake in the Poseidon project. The projects are described as floating wind turbines, between 25 and 27 kilometers off the Swedish west coast, north of Gothenburg.”
supportsoperatorco-developerFoundationDistance from shore
[4]
Swedish Government (Regeringen)2025-06◆ Nu kan havsvindparkerna Galene och Posei…
“Regeringen har idag fattat tre beslut om tillstand till kabelutlaggning, som ar en separat tillstandsprocess, for de redan tillstandsgivna havsbaserade vindkraftparkerna Galene och Poseidon.”
supportsStatusConnection point
Trade press4
[1]
offshoreWIND.biz2024-11-04◆ Sweden rejects 13 Baltic offshore projec…
Press report — cited, not quoted; read it at the source link.
supportsConsentSite rightsTurbinesTotal capacityFoundation+2 more
[5]
[6]
[7]