Methodology to calculate mooring and anchoring costs of floating offshore wind devices

Abstract

The aim of this article is defining a methodology which allows us to evaluate the main mooring and anchoring costs of floating offshore wind farms. In this sense, costs of most important phases of life cycle will be analysed: manufacturing, installation, exploitation and dismantling. For this purpose several models will be defined taking into account the type of floating offshore wind platform (semisubmersible, Tensioned Leg Platform or spar), mooring disposition (transitional no tensioned, slack no tensioned, tensioned with 90º or tensioned with 45º), mooring material (chain, cable and synthetic fibre) and type of anchor (drag embedment anchor, suction pile, gravity anchor and plate anchor). Finally the proposed method will be applied to know mooring costs of a substructure located in the region of Galicia (North-West of Spain). Results show how each of these costs depend on the model considered, which help investors to decide what the best model is.

Floating wind turbines: marine operations challenges and opportunities

“…Compared to the Hywind project, specialized expensive heavy-lift crane vessels were not employed here. Castro- Santos et al (2013) has observed that the installation of anchoring and mooring systems is less expensive using an AHTS compared to a combination of barges and tugboats. The Kincardine offshore floating wind farm is another project which employs semi-submersible floaters for the wind turbines (offshorewind.biz, 2021).…”

“…drag-embedded anchors, are easily recoverable, which would save costs and time (González and . There is an additional cost due to the cleaning of the wind farm site which is of environmental concern (Castro-Santos et al, 2016). Some materials can be sold as scrap, e.g.…”

“…Some materials can be sold as scrap, e.g. steel from the floater and copper from the electric cables, which would result in a negative cost (income) (Castro-Santos et al, 2016).…”

Reply on RC2

“…Compared to the Hywind project, specialized expensive heavy-lift crane vessels were not employed here. Castro-Santos et al (2013) has observed that the installation of anchoring and mooring systems is less expensive using an AHTS compared to a combination of barges and tugboats.…”