Comparação de diferentes tecnologias de baterias para sistemas solares fotovoltaicos conectados à rede

Abstract

Grid-connected photovoltaic solar power generation is a reality in Brazil, and its growing expansion presents both advantages and challenges for the electricity grid. In order to minimize the effects of climate dependence and generation peaks during sunny hours, the use of energy storage systems is a solution. However, the implementation and use of batteries also represents an increase in system costs and associated environmental impacts. In this work, three battery technologies were compared via the Vikor multi-objective decision method: Lithium-Ion, Lead-Acid and Nickel-Cadmium, with the aim of obtaining a recommendation for the system that best suits the parameters: carbon emissions and energy costs, technical performance, battery life and economic aspects. The decision algorithm is applied to situations where each parameter has the same weight, and to alternative scenarios where the decision has an environmental, economic, or electrical performance bias. To assess environmental aspects, cradle-to-grave life cycle assessment data is used, and the system is sized for a standard low-consumption home. This study found that the lithium-ion battery had the best performance among the aspects evaluated, with the lead-acid battery being intermediate and the nickel-cadmium battery being the technology furthest from the ideal solution. In alternative scenarios where decision-making favors environmental and electrical aspects, the lithium-ion battery is still recommended by the method. In a scenario where cost is prioritized, nickel-cadmium batteries were recommended.