Grid energy storage is the latest new generation technology of the era. It also called large scale energy storage refers to the systems used to store electricity on a huge scale within an electrical power grid. Electricity is stored at that time when production from power plants in essence intermittent renewable electricity sources including wind power, tidal energy, solar power and many others exceeds purchase so when extra discretionary load is turned on but purchase is still unavailable to absorb it. This article briefly explain some benefits of storage and managing peak load. Here also focus on demand side management and grid storage.