Aspects of the invention relate to system and method of storing off-peak electricity. The system includes an energy storage device electrically coupled to an electricity grid of at least one electricity provider, where the energy storage device has a storing capacity and is chargeable or dischargeable, upon demand, and a controller configured to control operation of the energy storage device such that the energy storage device is charged with the off-peak electricity at an off-peak time each day when a demand for electricity is low from the electricity grid, and is discharged at a peak time each day when the demand for electricity is high, to provide an amount of the stored electricity, to the at least one electricity provider.