**3. Environment Chosen for Installation**

The proposed installation will be simulated in the atmospheric conditions of Povoa de Varzim in Viana do Castelo, where the WindFloat Atlantic project is installed. The average wind speed in this location is presented in Figure 2.

**Figure 2.** Wind Speed (m/s) Variability at 100 m high.

In the following figure, we can see how the average wind speed varies during a year at the height of 100 m. This information was provided by the Global Wind Atlas website.

The data collected is for a height of 100 m, and our rotor is about 190 m high. The following equation, the logarithmic profile law, can determine the wind speed at a certain height, which is used to compute the values on Table 1.

$$\upsilon\_h = \upsilon\_{\rm an} \times \left| \frac{\ln(Z\_h/z\_0)}{\ln(Z\_{\rm an}/z\_0)} \right| \tag{4}$$

where *vh* is the e velocity at the desired height *Zh*, *van* is the velocity at the anemometer height *Zan* and *z*<sup>0</sup> is the surface roughness length, which is 0.005 m/s for the blown sea [13].

Unlike what happens with the wind, obtaining information about the currents' speed is very difficult. This information is scarce and hard to find. This information was provided by the Instituto Hidrografico (IH), which provided data on current speeds in 2015 at the chosen location.

**Wind Speed at 100 m Wind Speed at 190 m** Minimum 5.61 m/s 5.97 m/s Average 7.78 m/s 8.28 m/s Maximum 10.52 m/s 11.20 m/s

**Table 1.** Wind Speed at 100 m and 190 m.

Only the maximum and average values, on Table 2 of the current speed will be considered as the minimum value is null.



#### **4. Modelation**

The wind turbines used in the simulation will be identical to those used in the Wind-Float Atlantic project located in Povoa de Varzim because it is the only project of offshore wind energy in Portugal. The WindFloat Atlantic project has three V164-8.4 MW wind turbines mounted on the semi-submersible WindFloat platforms that are anchored to the seabed at a water depth of 100 m.

In the proposed project, we will use a turbine with the same specifications that an AR1500 tidal turbine. After analyzing the characteristics of PVDF and PZT, the piezoelectric materials chosen to apply in the structure were the PVDF. The PVDF model chosen was PROWAVE FS-2513P SENSOR, PIEZO FILM [14].
