Battery energy storage refers to the technology that allows energy to be stored in batteries for later use. This system captures excess energy generated from sources like solar panels or wind turbines and stores it for times when energy demand is high or when renewable sources are not producing energy. By doing so, it helps balance supply and demand, ensuring a stable energy supply. These storage systems can be used in various applications, from residential homes to large-scale utility projects. They play a crucial role in enhancing the reliability of the electrical grid and supporting the transition to cleaner energy sources, reducing reliance on fossil fuels.