Kumagai Gumi Signs On to Saitec's DemoSATH Floating Wind Pilot Off Spain as Operations Run to 2027

DemoSATH, the floating offshore wind demonstrator operating off the Basque coast of Spain, has entered a new phase centred on research and knowledge generation, backed by the arrival of Japanese general contractor Kumagai Gumi as a strategic partner.

A cooperation agreement between Saitec Offshore Technologies, The Kansai Electric Power Company Co. Inc. (KEPCO), which was already part of the project, and Kumagai Gumi will keep the prototype running at the BiMEP open-sea test site in Armintza, Bizkaia, through 2027. Work during this period will centre on research, optimisation and knowledge transfer.

Contractor Skills Directed at Decommissioning and Mass Production

Kumagai Gumi's role in the project draws on its position as a general contractor in the construction sector. The company is expected to concentrate on two specific areas: refining decommissioning methods for future projects and assessing rationalised construction procedures suited to mass production.

Three Years of Offshore Operations Behind the Shift

The transition to a research-focused phase comes three years after DemoSATH began operating. In that initial period, the demonstrator validated the installation, operation, and power generation of the SATH floating technology under real offshore conditions while gathering data on its structural, dynamic, and operational behavior. Alongside this, the DemoSATH Lab initiative turned the platform into a living laboratory where trial systems and solutions were tested to support coexistence with the marine environment, promote biodiversity, and investigate possible aquaculture applications.

Conditions at the site have tested the turbine hard. Standing in the Cantabrian Sea, the unit has endured waves reaching 13 meters and wind gusts of 144 km/h. Instrumentation on the platform and its monitoring systems have recorded operational data in real conditions, allowing measured behavior to be compared against the models drawn up during the design phase. Saitec Offshore Technologies describes the shift as a natural evolution of the project.

With the technical feasibility of the SATH Technology demonstrated, the infrastructure and the experience built up over three years will now serve as a full-scale research and testing platform, with lessons transferred to future large-scale commercial projects across different international markets.

Research Agenda for the Extended Campaign

The work program for the extended run covers a wide span of research and testing areas in floating offshore wind. Among the planned activities are optimized monitoring of key system components, data analysis and predictive modelling, and characterizing how floating wind systems respond across a broad range of offshore conditions.

The research will draw on the extensive operational data that DemoSATH has generated to deepen understanding of floating wind technology and inform the development, design, and optimization of future commercial-scale floating offshore wind projects.

Platform Details and Path to Commercial Application

The DemoSATH unit pairs a 2 MW wind turbine with a concrete twin-hull floating structure. It is installed roughly 3.2 kilometres off the Basque coast in water around 85 metres deep. The platform was built and assembled at the Port of Bilbao and then towed to its berth at BiMEP.

With Kumagai Gumi on board and operations extended to 2027, the project moves from demonstrating the technology to generating knowledge aimed at commercial application. According to Saitec Offshore Technologies, this reinforces DemoSATH's role as a reference platform for the development of floating offshore wind.