A recent study performed by the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL) is helping Norway-based Statoil prepare for the installation of what has the potential to be the world’s first multi-turbine floating offshore array.
Statoil deployed the first spar-based system called Hywind Demo in 2009, which is still operating today. The company partnered with NREL from March 2013 to March 2015 to analyze the Hywind technology as applied to U.S. waters.
Floating offshore wind turbine technology has significant potential for being a clean, sustainable source of energy. The technology is feasible above transitional water depths of 50 meters, where fixed-bottom structures are economically challenged. Floating wind turbines have the unique ability to access robust wind resources that are often higher and more available than in shallower water—thereby lowering the cost of energy by increasing power production.
Senu Sirnivas, a principal engineer at the NWTC , said: “At NREL, we have developed several tools to evaluate offshore wind system performance and costs. Our team was very encouraged to know that Statoil saw value in our work, and that these NREL tools and analyses were helping inform what can be the first multi-turbine floating wind turbine array. Developing software tools that are at the cutting edge was thrilling.”
Sirnivas added, “Through this unique experience, we were able to get practical and experience-based feedback, which is going to inform our future work.”
The original study in budget period 1 used a 3-megawatt (MW) Hywind system and focused on design and analysis, turbine size-up scaling, the mooring system, instrumentation, data acquisition, and economic analysis. During budget period 2, the focus shifted to a 6-MW Hywind system and included design and analysis, wake modeling, and geo-spatio-economic assessment.
NREL presented Statoil with a report on each of its work packages, and the company may use the results of the collaboration to guide its future projects. NREL researchers have also presented Statoil with proposals for future collaborative efforts.