EnergyOMNI's Perspectives｜Norway's TetraSpar Floating Wind Demonstrator to Be Decommissioned in 2026 Summer

Edited by EnergyOMNI

The TetraSpar floating offshore wind demonstrator, located off the coast of Norway, is scheduled to be decommissioned this summer, marking the conclusion of a five-year testing program. TetraSpar began operations in November 2021, with an installed capacity of 3.6 MW. It is equipped with a Siemens turbine and utilizes a semi-submersible floating platform.

The demonstrator project is jointly owned by Stiesdal Offshore, RWE, and TEPCO Renewable Power, with an estimated cost of approximately USD 50 million. During its operation at the Norwegian METCentre test site, it generated nearly 70 million kWh of electricity, achieving a capacity factor of 51.4% and an availability rate of 98%.

TetraSpar recently announced that the decommissioning work has been awarded to Norwegian contractor Global Maritime. The scope includes recovery of the entire structure for comprehensive inspection, while ensuring safety, efficiency, and environmental responsibility throughout all phases.

During the offshore phase, key subsea components will be disconnected, recovered, and handled, including the inter-array cable and the station-keeping system. These components will be removed and sent for appropriate recycling. The complete TetraSpar structure will then be towed to a deep, sheltered location for temporary mooring. After keel handling operations, the structure will be transported back to port for docking.

Once onshore, systematic dismantling of the main components will begin. The wind turbine will be disassembled, with the nacelle and rotor sent to designated processing facilities. The tower sections, keel, and floating structure will undergo material segregation, marine growth removal, waste treatment, and industrial recycling. Global Maritime stated it will collaborate with subcontractor Semco Maritime at the Hanøytangen shipyard for these operations.

Henrik Stiesdal, Chairman of TetraSpar Demonstrator ApS, stated: “The TetraSpar demonstrator has shown that floating wind concepts can operate reliably over extended periods under real offshore conditions.” He added that through full structural inspection, “we will gain further knowledge to support the continued development and scaling of floating offshore wind, helping bring the technology closer to commercial deployment.”

Throughout the testing period, more than 40,000 hours of operational data were collected through continuous monitoring. Post-decommissioning analysis will not only provide insights into long-term material behavior, corrosion, and hydrodynamic performance, but will also support future certification standards and supply chain development for floating wind.

The decommissioning is also seen as an important opportunity as the industry moves toward commercial-scale floating wind farms. Analysis of the modular steel floating structure is expected to help reduce technical and financial risks for large-scale projects. As the sector advances toward gigawatt-scale development in deeper waters, decommissioning data will become an increasingly valuable asset.

Several megawatt-scale floating offshore wind demonstrators have already completed the decommissioning phase. For example, following the 2011 Fukushima nuclear disaster, Japan deployed multiple floating wind demonstrators off the coast of Fukushima under the Fukushima FORWARD project, using semi-submersible platforms. The 7 MW turbine was decommissioned in 2018, while the remaining 2 MW and 5 MW units were decommissioned in 2021.

The WindFloat 1 floating wind demonstrator located off the coast of Portugal also used a semi-submersible platform and was equipped with a 2 MW Vestas turbine. Installed in 2011, WindFloat 1 completed its demonstration objectives after five years of operation and was decommissioned in 2016.

According to the Global Wind Energy Council’s Global Offshore Wind Report 2025, global installed capacity of floating offshore wind reached 278 MW by the end of 2024. Research firm Research Nester estimates that the global floating offshore wind market will exceed USD 104.2 billion by 2035, with a compound annual growth rate (CAGR) of over 47.7% from 2026 to 2035. MarketsandMarkets provides an even more optimistic outlook, projecting the market to grow from USD 3.16 billion in 2026 to USD 25.4 billion by 2031, at a CAGR of 51.7%.

In Taiwan’s 2050 net-zero emissions pathway, floating offshore wind is clearly identified as one of the key strategies. The Ministry of Economic Affairs(MOEA) began planning a demonstration program in 2021 and held consultation meetings with the industry in 2022, 2023, and 2024 to gather feedback. The current draft proposes developing two to three demonstration projects, targeting grid connection by 2030. With the recent launch of Round 3-3 of offshore wind zonal development, the MOEA has also announced plans to initiate floating wind demonstration projects in 2026, with public consultation expected in the first half of the year and discussions on feed-in tariffs in the second half.