The columns provide the hydrostatic stability, and pontoons provide additional buoyancy.
Semi-Submersible Platform Foundation: Semi-Submersible Platform Foundations (Fig.2) are a number of large columns linked by connecting bracings / submerged pontoons. It is estimated that the project will reduce emissions from the Gullfaks and Snorre fields by more than 200,000 tonnes per year. Equinor installed the first ever floating offshore wind turbine in 2009, and operates Hywind Scotland (30 MW), the world’s first floating wind farm. 1 Completely Installed Spar-Buoy Foundation by Jochem Tacx. Located 140 km from the Norwegian coast, the Hywind Tampen wind farm will be, at the time of its commissioning, the largest floating offshore wind farm in the world, and also the first to supply energy to an offshore oil and gas field Gullfaks and Snorre. The Hywind Tampen project, the first floating offshore wind project to supply renewable power for oil and gas installations will have a total capacity of 88 MW, and is expected to cover about 35 percent of the annual power needs on the five platforms Snorre A and B and Gullfaks A, B and C. Overall, by using larger turbines, concrete substructures, new technology and a new assembly method, Equinor hopes to drive down costs of floating wind turbines by more than 40% from its current Hywind Scotland installation. The slipform system is designed and supplied by German engineering company Dominion and can be used multiple times, providing and more cost-effective method for faster construction. Aker Solutions is responsible for the engineering, procurement, and construction of the foundations under a contract worth around USD178 million. At 1GW, this project would be over 30 times bigger than Hywind Scotland, the UK’s and Equinor’s first floating project and have the potential to not only position Scotland as a leader in deep. The foundations are concrete SPAR-type hulls that will be constructed using the slipform method. The foundations for Equinor’s 88 MW Hywind Tampen project is being constructed in Stord.