Photovoltaic (PV) solar farms and hydropower stations can create a plant that do more than the two resources acting independently as long as, with the addition of a solar project, hydroelectric plants increase its annual availability of power and economic efficiency, taking advantage of the storage capacity of energy that a hydroelectric reservoir can provide. The objective of this paper is to investigate the potential of Brazilian hydropower plants regarding these issues using the large amount of available data recorded. There exists a potential increase in the energy production of 53.3 TWh per year based on the proposed optimized solution for the Brazilian hydropower stations with significant water storage capacities assessed in this paper. This energy is equivalent to an additional capacity factor of approximately 20% to the original 31.5 GW installed hydro capacity or almost 10% of the Brazilian electricity demand in 2018. This result would be at the expenses of a huge deployment of 34 GW of solar PV floating power plants installed close to the reservoir dams that must yet prove to be economically feasible. However, on the other hand, this proposal can create a virtuous cycle for the solar industry in Brazil and speed up the viability of solar cell costs, since setting up and connecting the PV plants are greatly simplified when done in existing hydropower stations facilities.
energy storage, floating photovoltaic, hybrid power plant, hydropower
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