Potential of residual energy from hydroelectric dams for hydrokinetic park projects under the influence of the CMIP6 climate scenario in Brazil

Abstract

ABSTRACT The use of hydrokinetic energy downstream of hydroelectric dams through hydrokinetic parks presents itself as an interesting opportunity to increase renewable energy generation. The determination of this potential, in the face of climate change, remains a gap in the literature. This article assessed the future hydrokinetic potential, integrating climate projections (SSP5-8.5 scenario), two-dimensional hydrodynamic modeling (iRIC v4, Nays2D+ solver), and the coupling of the logarithmic law for the determination of velocity profiles (quasi-3D). The method was applied downstream of the SEFAC hydroelectric power plant (HPP), located in the Brazilian Cerrado. The results indicated reductions in flow rates and velocities. Thus, three design options for the hydrokinetic park were presented: 1- operation for a longer time, considering the Q95% flow rate, but with lower energy generation; 2- operation for a shorter time, considering the Q50% flow rate, but with higher energy generation; and 3- operation for a longer time than option 2, i.e., using the Q75% flow rate, but with energy generation of the same order of magnitude. In this case, a hydrokinetic park operating 75% of the time is a very interesting alternative, even though the energy generated is slightly less than the alternative operating 50% of the time.