Avaliação das energias eólica e solar fotovoltaica para o estado de Alagoas, com ênfase para complementaridade

Abstract

The present work presents a study of wind and solar mapping in the state of Alagoas, northeastern Brazil. The Weather Research Forecast (WRF) model was used with atmospheric stability and terrain slope approximations for the finest grid refinement (250m resolution) so that areas with the greatest utilization of wind resources could be identified. The WRF-SOLAR, an extension of WRF, was used as it is an enhanced tool with physical improvements, designed to meet the needs and applications related to solar resource exploration. Atmospheric simulations were run daily for a period of 8 years (2008 - 2015). Wind and solar radiation pattern estimates were statistically validated with surface-level anemometric and meteorological measurements in the following mesoregions (cities): semi-arid (Água Branca, Pão de Açúcar), agreste (Girau do Ponciano, Palmeira dos Índios), and coastal (Maceió, Maragogi, Roteiro). Regarding wind resources, a predominant wind direction was observed varying between East/Southeast. Statistical metrics indicated a satisfactory representation of atmospheric simulations, validating the proposed grid reduction method. The spatial variability of the results emphasized that the inclusion of atmospheric stability and slope allowed for a clearer representation of the topography and surface roughness. Promising areas for wind utilization were identified in the mountainous regions of Água Branca, Palmeira dos Índios, and Feliz Deserto, with an annual intensity above 7 m/s at 100m height and energy production capacity exceeding 2500 kWh/kWp. Concerning solar resources, WRF-SOLAR reasonably estimated solar radiation with average statistical metrics for correlation (0.85), BIAS (75.7 W/m²), and RMSE (210.51 W/m²). Results showed that the territory of Alagoas is favorable for distributed generation due to abundant solar radiation, averaging 6.5 kWh/m² and reaching minimum attractive limits for investments in photovoltaic energy generation. Therefore, spatial productivity varies between 1558 and 1916 kWh/kWp. Regarding complementarity, the use of the Pearson correlation coefficient between wind and solar resources revealed no correlatio for the city of Poço Branco, indicating the limited effectiveness of complementarity between these resources. Additionally, by adopting this location as promising, scenarios of hybrid generation revealed that greater grid stability occurs with a higher predominance of solar generation.