Energy storage refers to the capture of energy produced at one time for use at a later time. This technology is crucial for balancing supply and demand in energy systems, especially with the rise of renewable energy sources like solar and wind. By storing excess energy, we can ensure a reliable power supply even when production is low. There are various methods of energy storage, including batteries, pumped hydro storage, and compressed air energy storage. Each method has its own advantages and applications, making energy storage a vital component in the transition to a more sustainable energy future.