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Figure 5 – Wave energy converters developed by COPPE/UFRJ 5.2 Tidal energy of 2.5 m was considered. The new model
eliminates the need to use stop-log gates
a) hyperbaric converter
The coastal areas of Maranhão, Pará to control the maximum limit of the res-
and Amapá are the regions with the high- ervoir. Annual energy production of ap-
est tidal ranges in Brazil. The tidal energy proximately 14 GWh/year was estimated,
potential of 22 TWh/year was estimated considering the Kaplan turbine with dual
for the state of Maranhão (NETO et al., regulation supplied by Andritz Hydro (AG-
2017). Some studies have addressed the GIDIS et al., 2012). Another study was
exploitation of this energy in Brazil (FER- carried out by Ferreira and Estefen (2009),
REIRA et al., 2009; NETO et al., 2015). The considering the restrictions of the Bacanga
10,219-ha estuary of the Bacanga River, Dam to propose alternatives to be incor-
which includes the estuarine body of wa- porated into an adaptation project aimed
ter and Lake Bacanga, has a capacity of at constituting a pilot tidal power plant.
about 40 million cubic meters at a height The possibility of converting tidal currents
of 4.5 m, corresponding to the tide level depends on identifying the flow of high
of spring (NETO et al., 2017). The Bacanga and low tides from in situ measurements
dam has a rocky slope, with an extension (FERREIRA et al., 2016).
of 800 m, filled with clay material. There
(b) converter with latching control are two radial and stop-log gate systems 5.2.1 Offshore wind
that were installed in 1974 and 1980 re-
Heave spectively. The three radial gates are ap- Currently, there are no offshore wind
Stem
proximately 12.5 m wide. In the case of a turbines installed along the Brazilian coast.
Generator Topside fully open gate, a water level of 4.5 m is However, according to IBAMA, 23 projects
System
recorded for each radial gate. This value is have already started the environmental li-
about 3 m for stop-log type gates, which censing process, with a total installed ca-
Columns
are flat and work vertically, with widths of pacity of around 47 GW. Considering an
2.85 m (SHADMAN et al., 2019). Neto et average capacity factor of 50%, this means
Bearings al., proposed a new model for this dam 32% of the national electricity demand in
in which the three radial gates would be 2020. The offshore wind farm projects sub-
replaced by others suitable for automat- mitted to IBAMA are located in the states
Buoy ed operation. A reservoir water level limit of CE, PI, RN, BA, RJ and RS.

6. Regulatory aspects in Brazil

In Brazil, the concession and licensing locations where the reservoirs can be ex-
processes for offshore oil and gas and on- plored. The pre-development phase in-
shore wind by the Brazilian National Agen- cludes the concession/license of the area to
Base Seafloor
cy of Petroleum, Natural Gas and Biofuels carry out preliminary studies. ANEEL (Na-
(ANP) are based on the bidding system, in tional Electric Energy Agency) is the regula-
Source:
COPPE/UFRJ which the regulatory body offers specific tory agency responsible for the concession

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