## 1 Introduction
The National Integrated Climate and Energy Plan, published in 2019, foresees a significant growth in the onshore wind capacity by 2030, with a target of 18.4 GW, and a cautious starting of the offshore wind sector with a target of 0.9 GW--corresponding to approximately two-three offshore wind farms of the present average size. This \"cautious\" target is due to two main factors. The first is that most of Italy's offshore wind potential corresponds to marine areas with deep waters, where there is, at present, no commercial technology available for the installation. The second is that the offshore wind resource is, on average, lower than the northern Europe seas and oceans. Both of these factors question the economic sustainability of future floating wind initiatives in Italy. The purpose of this study was to conduct a technical-economic analysis regarding future floating offshore wind installations in Italy. The uncertainty factors in this analysis were high, mainly due to the lack of in-field data about the costs of construction, installation, and maintenance of such plants, and to the high uncertainty of the assessment of the offshore wind resources due to the lack of (long-term) direct measures. However, understanding in advance the factors affecting the economic sustainability of floating wind plants in Italy is quite important to plan future development and to eventually anticipate the design of support measures. The performed analysis was based on similar studies conducted by authors in the past [9; 10], and available in the literature for other geographical areas [11; 12; 13]. Two scenarios were considered: the first scenario starts from 2030; according to Italy's 2030 offshore wind target, the majority of offshore wind development in Italy is expected beyond 2030. At this time, on the basis of International Renewable Energy Agency (IRENA) assumptions [14], the floating offshore wind technology is considered fully commercial. For the second scenario, the authors went so far as to analyze a second generation of floating wind farms, starting from 2060. In this scenario, cost reductions due to a probable widespread diffusion of these types of plants, and possible variations of the wind resources due to climate change, were considered. Regarding the estimation of this last parameter, there is an uncertainty due to the different approaches and models through which its prediction is performed. A conservative approach was chosen considering the higher negative variations in three offshore areas in Italy (Sicily, Sardinia, and Apulia). The economic model chosen to perform the analysis is the Levelized Cost of Energy (LCoE). This parameter, albeit with limitations, is still one of the most used to conduct comparative economic analyses among different technologies or among different scenarios inside the same technology, such as those presented here. LCoE depends on both the total costs and the energy production throughout the life of the plant. The costs themselves are dependent on many factors: in this study, as a first approximation, they were parameterized as a function of the distance from shore. The costs also depend on water depth. Going farther from the coast usually means meeting higher water depth; however, the relationship is strongly affected from the bathymetry shape, and is very different from area-to-area, and even from site-to-site. In this study, the water depth is considered fixed. Another assumption was to consider average costs for different technologies. This is mainly because the complete sets of inputs needed for the evaluation were not available for different technologies. Moreover, there is no consensus in the literature about the cost differences among technologies. The costs assumed in this study refer to an average between monocolumn and semi-submersible platform. Different energy production (or capacity factor) values were also chosen representing different geographical offshore areas in Italy. Finally, the LCoE depends on financial parameters.