Analysis of Complementarity between Renewable Sources in River Basins: a Proposed Methodology and a Brazilian Case Study

Abstract

Abstract Exploring the natural complementarity that exists between renewables is pivotal for optimizing clean electricity generation. Quantifying this complementarity can enhance electrical planning, reducing waste of natural resources and guiding investment decisions more effectively. To quantify the complementarity existing in Brazilian river basins, a methodology was proposed. Data on influent natural energy, irradiance, and wind speed are analyzed using Python. Through a comprehensive process, the most suitable correlation coefficient is identified. The subsequent calculation of coefficients for specific source combinations and periods, as well as the application of the Innovative Trend Analysis methodology, allow an understanding of the existing complementarity dynamics. The methodology was applied to the Capivari River basin, located in the state of Paraná, which included a monthly analysis of complementarity between hydraulic generation with wind and photovoltaic sources from June 2016 to April 2024. There was no discrepancy in the interpretations of the results obtained for Spearman’s Rho and Kendall's Tau, although the magnitude of Kendall's Tau is, on average, 30% lower for the combination of photovoltaic and hydraulic and 49% for the combination of wind and hydraulic. The combination of wind and hydraulics exhibited seasonal complementarity, demonstrating lesser advantages compared to photovoltaic generation, with around 61% of the acquired values of Spearman’s Rho being negative, approximately 28% of which were negligible. This percentage is lower than the over 82% of negative values observed for the photovoltaic and hydraulic combination, of which 12% are negligible. The results are consistent with the literature and validate the proposed methodology.

Keywords

• Brazilian case study
• complementarity
• correlation coefficients
• renewable energy sources
• river basin