Floating Offshore Wind: How It Works and Where It's Headed
Updated October 5, 2026
Floating offshore wind mounts wind turbines on buoyant platforms anchored to the seabed with mooring lines, instead of on foundations fixed to the sea floor. It opens up deep-water areas, generally deeper than about 60 meters, where much of the world's strongest offshore wind resource lies.
Why floating matters
Most offshore wind farms today use monopiles or jacket foundations driven into the seabed. They are economical only in relatively shallow water. Many coastlines drop off quickly into deep water, including the U.S. West Coast, Japan, Norway and parts of the Mediterranean. Floating platforms make offshore wind possible there.
The main platform types
- Spar-buoy: a long, ballasted cylinder that extends deep below the surface for stability. Very stable but needs deep water at the assembly port. Used at Hywind Scotland.
- Semi-submersible: a platform of several connected columns that floats partly submerged. It can be assembled in port and towed out, which makes it the most common design in current projects. Used at Kincardine (Scotland) and WindFloat Atlantic (Portugal).
- Tension-leg platform (TLP): held down by taut vertical tendons. It has a small footprint and little motion, but more complex anchoring.
- Barge: a wide, shallow hull with a central opening that damps wave motion.
Key projects to date
- Hywind Scotland (2017), about 30 MW, the world's first floating wind farm.
- WindFloat Atlantic (Portugal, 2020), about 25 MW.
- Kincardine (Scotland, 2021), about 50 MW.
- Hywind Tampen (Norway, 2023), about 88 MW, supplying power to offshore oil and gas platforms.
Global floating capacity is still small, only a few hundred megawatts. Much larger commercial projects are in development in the UK (the Celtic Sea and ScotWind leases), France, South Korea, Japan and the United States. In the U.S., lease areas were auctioned off California (Humboldt and Morro Bay) in 2022 and in the Gulf of Maine in 2024.
Challenges
- Cost: floating wind is still significantly more expensive per MWh than fixed-bottom offshore wind. Cost reductions depend on building at scale.
- Ports and supply chain: large turbines must be assembled onto platforms at deep-water ports, and few such ports exist today.
- Dynamic cables and moorings: power cables must flex with platform motion, and mooring systems must survive extreme storms.
- Transmission: new offshore sites often need major onshore grid upgrades.
- Policy and market conditions: higher interest rates and supply costs have delayed or reshaped many offshore wind projects since 2022.
Bottom line
Floating offshore wind has proven it works technically. The question now is economics: can industrial-scale manufacturing, ports and supply chains bring costs down the way fixed-bottom offshore wind did in the 2010s? Watch the first gigawatt-scale projects later this decade for the answer.
Frequently asked questions
How deep is the water for floating offshore wind?
Floating platforms are generally used in water deeper than about 50–60 meters, where fixed foundations become uneconomic, and can work in several hundred meters of depth.
What was the first floating wind farm?
Hywind Scotland, a roughly 30 MW project that began operating in 2017.
Is floating wind more expensive than fixed offshore wind?
Yes, currently by a significant margin. Costs are expected to fall as projects scale up.