Storage technologies include pumped hydroelectric stations, compressed air energy storage and batteries, each offering different advantages in terms of capacity, speed of deployment and environmental impact. . Grid energy storage is vital for preventing blackouts, managing peak demand times and incorporating more renewable energy sources like wind and solar into the grid. There are many sources of flexibility and grid services: energy storage is a particularly versatile one. Lithium-Ion Batteries: Known for their high energy density and efficiency. As the cost of solar and wind power has in many places dropped below fossil fuels, the. .