Sustainable future and water resources: a synthesis of the Brazilian hydroelectricity sector in face of climate change

The Brazilian electricity production and transmission system have a significant predominance of hydroelectric generation and are vulnerable to climate change. Thus, the present paper draws up a compendium of the primary studies that discuss vulnerabilities to climate change and the need to implement adaptation measures in the Brazilian electricity sector to guarantee a sustainable future. To integrate this bibliographic review, observed data on air temperature, precipitation, and streamflow in the drainage areas of Brazilian hydroelectric power plants were collected and analyzed, especially from the second half of the twentieth century to the 2000s. The significance and magnitude of trends were calculated and evaluated using the Mann–Kendall non-parametric statistical test and Sen’s Curvature. A case study of future projections is also discussed for the twenty-first century through hydroclimatic modeling (Eta regional climate model and SMAP rainfall-runoff model). Observed trends show that the patterns of temperature, precipitation, and streamflow are changing in Brazil. The air temperature is increasing in much of the territory. Also noteworthy is the decrease in rainfall and streamflow over the northern Paraná River basin and the increase in most of the Southern region of Brazil. Long-term projections indicate significant effects of climate change on energy production in Brazil. The simulations point to a drier scenario in the central northern portion of Brazil and a wetter scenario in the southern sector over the following decades. So, the literature review reinforces that it is fundamental development, improvement, and implementation of integrated management policies between water and energy. Also, the Brazilian electrical system needs to consider all available renewable sources, besides investing in efficient technologies.