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the increase in their dimensions (DEWAN et   followed by the jacket. Projects implemented                          3. Potential of resources
              al., 2015). To overcome this problem, float-  at greater depths make use of floating foun-
              ing concepts were proposed. As shown in   dations. So far, the only commercial floating                               This section uses four main works: SHAD-  margin of Brazil, with a velocity of 1.52 m/s.
              Figure 4a, the type of fixed foundation can   wind farm is Hywind Scotland, installed at                           MAN  et al.,  2019, HERNANDEZ C.  et al.,   This region is located at a distance between
              be categorized into four types including   the end of 2017, which includes five float-                             2021 and ASSIS TAVARES  et al., 2021,to   120 and 300 km from the coast, with power
              gravity base, monopile, tripod and jacket.   ing wind turbines, with a spar foundation,                            present the renewable resources in the ocean   density values above 500 W/m2. However,
              The floating foundation can be catego-    with 6 MW turbines. Some examples of the                                 along the Brazilian coast. The wave dataset is   the long distance from the coast implies
              rized into three types: semi-submersible,   semi-submersible type are the Windfloat, Sea                           obtained using Météo-France’s global ocean   substantial costs of submarine cables, which
              spar, and tension-legged platform (TLP), as   Angle, Eolink Prototype and Kincardine proj-                         analysis and forecasting operating system   can make the project of transmission of
              shown in Figure 4b. The monopile founda-  ects, which are in the demonstration phase                               which is available for the CMEMS (Coper-  electricity to the mainland unfeasible.
              tion is the most used in existing installations,     (WIND EUROPE, 2019).                                          nicus Marine Environment Monitoring Ser-    According to SHADMAN  et al. 2019,
                                                                                                                                 vice). The model has a horizontal resolution   along the Brazilian coast, except for the
                               Figure 4 - Offshore wind turbine foundations                                                      of 1/12° (~9 km) and 3-hour instantaneous   extreme south region, below 27°S, the
                                                                                                                                 fields of built-in wave parameters. Datasets   average annual thermal variation, which
                a – Fixed foundations                                                                                            for ocean currents velocity and temperature   represents the thermal difference between
                        Gravity    Monopile        Tripod        Jacket          Tripile                                         were obtained (surface up to 5500 m) from   depths of 20 m and 1000 m, is about 20°C
                      Foundation   Foundation   Foundation     Foundation      Foundation                                        the numerical model product available for   or higher. The authors considered twelve
                                                                                                                                 CMEMS. The dataset has a regular horizontal   10 MW OTEC plants along the coast. The
                                                                                                                                 grid with a resolution of 1/12° (~9 km) based   selected  points  are  at  distances  between
                                                                                                                                 on the tripolar ORCA grid (GM, 1996), 50   30 and 200 km from the coast. The North
                                                                                                                                 vertical levels with 22 layers within the top   and  Northeast  regions  have  higher  aver-
                                                                                                                                 100 m of the surface, the bathymetry of ETO-  age annual power compared to the South
                                                                                                                                 PO1 (AMANTE, 2018), and atmospheric forc-  and Southeast regions. The results showed
                                                                                                                                 ings from the ECMWF (European Center for   that the thermal difference of 20 °C can be
                                                                                                                                 Medium-Term Weather Forecasts).          reached at depths of up to 500 m in the
                                                                                                                                    According to SHADMAN  et al. 2019,    northeast region. In economic terms, there
                                                                                                                                 the total power of the wave energy was   is considerable cost savings for raising the
                                                                                                                                 estimated at 91.8 GW along the coast,    cold water to 500 m instead of 1000 m.
                b – Floating foundations
                                                                                                                                 considering the length of the Brazilian     The Brazil’s Energy Research Office (EPE
                                                                                                                                 coast. In practice, only a small portion of   - Empresa de Pesquisa Energética do Bra-
                                                                                                                                 this value can be extracted by wave energy   sil) estimated the offshore wind potential
                                                                                                                                 conversion devices, due to different issues   in the exclusive economic zone of Brazil
                                                                                                                                 associated with technical challenges, envi-  at 1.78 TW (MME, 2022), with about 700
                                                                                                                                 ronmental impacts, economy, differentiat-  GW in regions of depths up to 50 m (EPE,
                                                                                                                                 ed use of the maritime area and social im-  2020). In the study, the 10 MW DTU wind
                                                                                                                                 pacts. However, only a fifth of this poten-  turbine was used to calculate the  energy
                                                                                                                                 tial is equivalent to about 35% of Brazilian   production  and the capacity factor. The
                                                                                                                                 electricity demand in 2017 (EPE, 2018).  results shown by Hernandez C. et al., re-
                                                                                                                                    A maximum annual average of ocean cur-  veal the existence of three areas of inter-
                                                                            Source: (C. et al., 2021)                            rent can be observed in the north equatorial   est in the Northeast, Southeast and South


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