Pumped Hydro Storage is a method of storing energy by using water. It works by pumping water from a lower reservoir to an upper reservoir during times of low energy demand. When energy is needed, the stored water is released back down, passing through turbines to generate electricity. This system is highly efficient and can quickly respond to changes in energy demand. Pumped Hydro Storage is often used in conjunction with renewable energy sources like solar and wind to balance supply and demand, making it an important part of modern energy systems.