Economic Potential of Industrializing Floating Wind Turbine Foundations

Abstract

The potential of offshore wind is enormous. It could meet Europes electric energy demand seven times over, and the United States energy demand four times over. However, much of the offshore potential is at water depths that can only be served by floating systems. In order to truly enable floating offshore wind, the cost of energy needs to reach the level of fixed-bottom offshore wind. At the present time, a number of suppliers are offering floating offshore wind foundations, but at cost levels that are prohibitive for large-scale application. The root cause of the high cost levels is that existing designs have emerged from the offshore oil and gas sector; they are manufactured using conventional, non-industrialized methods, weights are measured in thousands of tons and manufacturing times are measured in months. In contrast, the TetraSpar concept is based on the application of proven design and manufacturing technologies from the highly competitive wind industry. As a result, the weight is only a fraction of the weight of other floating wind turbine foundations, manufacturing takes place in factories using industrialized methods, and assembly and installation is measured in days or weeks, not months. The foundation and wind turbine can be installed in any port of a reasonable size using a standard, land-based crane, and the complete assembly can be towed to site and hooked up to the moorings and the electrical cable using standard tugs. This paper presents how these desirable economic traits of the TetraSpar design are achievable, and how the near future feasibility of offshore floating wind turbines may develop as a consequence of this radical change in cost levels.

Floating wind turbines: marine operations challenges and opportunities

“…The TetraSpar has been developed with the aim to implement large-scale industrial production as it consists only of cylindrical tubes bolted together. These platforms do not require specialized vessels for installation since they can be towed using lowcost and widely available tugs (Andersen et al, 2018). The towing vessels and the FOWT must satisfy the stability criteria set by a classification society (Hartmann et al, 2017;DNV, 2021).…”

Reply on RC2

“…The TetraSpar has been developed aiming to implement large-scale industrial production, as they consist only of cylindrical tubes bolted together. Theses platforms do not require specialized vessels for installation since they can be towed using low-cost and widely available tugs (Andersen et al (2018)). As mentioned above, different types of FOWTs have advantages and disadvantages when it comes to installation, O& M and decommissioning.…”

Technical Definition of the TetraSpar Demonstrator Floating Wind Turbine Foundation

“…By adhering to this design philosophy, the TetraSpar demonstrator is expected to mark a step change in the LCOE of the FOWT sector, as detailed in [7]. The TetraSpar demonstrator has served as the first validation of relying on existing industrialized offshore wind supply chain for fabrication of a FOWT, with components now enroute for assembly at port.…”