ASSESSING THE RELATIONSHIP BETWEEN CLIMATIC VARIABLES ON HYDROPOWER GENERATION AT SHIRORO DAM A SIX-YEAR ANALYSIS AT SHIRORO DAM, NIGERIA

Abstract

Climate change poses significant challenges to hydropower operations by altering hydrological and meteorological processes that influence reservoir inflow and water loss. This study assessed the impact of rainfall, evaporation, and relative humidity on electricity generation at the Shiroro Hydropower Plant, Nigeria, using daily data spanning six years (2,192 days). Meteorological data were obtained from relevant meteorological records, while electricity generation data were sourced from Shiroro plant operational records. Seasonal disaggregation was applied to distinguish wet-season rainfall contributions to reservoir inflow (May–October) from dry-season evaporation and humidity-driven water losses (November–April). Simple and multiple linear regression analyses were employed to quantify climate generation relationships. Results indicated that rainfall had no statistically significant effect on electricity generation (R² = 0.002, p = 0.124), while evaporation and relative humidity exhibited statistically significant but weak relationships with generation (R² = 0.008, p = 0.014). Although these variables were statistically significant, the extremely low R² values indicate negligible practical explanatory power, suggesting that other hydrological and operational factors dominate generation variability. Independence of residuals was assessed using the Durbin–Watson statistic, though tests for normality and multicollinearity were not explicitly reported. The study concludes that local meteorological variables alone are insufficient to explain hydropower generation variability and recommends catchment-scale hydrological monitoring and integrated watershed management for improved climate adaptation strategies.