Cost modelling of floating wind farms with upscaled rotors in Maltese waters

Abstract

The technical viability of offshore wind projects depends upon a number of factors such as the site-specific wind resource, sea depth, seabed composition, distance to the shore and climatic conditions amongst others. The Mediterranean is characterised by deep seas relatively close to the shore and only a reasonable wind climate if compared to conditions in countries that are forerunners in the offshore wind sector. The development of floating wind turbine support structures will allow wind farms in deeper waters and will be a catalyst for the wider diffusion and larger-scale implementation of offshore wind farms on a global level. This study investigates the prospects for a hypothetical 100 MW floating offshore wind farm well to the west of the island of Malta. The study models three upscaled turbines having rotor diameters of 126, 145 and 170 m. The study shows that the rotor upscaling process can improve the economic viability of offshore wind turbines with the improved energy yield counterbalancing the higher investment costs required for such a project and thus resulting in a lower cost of energy. The levelised cost of electricity is estimated to be in the 21.0 to 23.6 €cent/kWh range which, although still well above the current market prices of electricity generated by conventional means, is expected to drop considerably over the coming years as new international players enter the offshore wind market. Increasing levels of competition, new concepts coming to fruition and wider and larger-scale diffusion of new technologies will help bring down costs of energy for the offshore wind farms of the future.