Energy storage can be confusing. The technology adds value to electrical systems by charging when there is excess energy on the system, storing the power until it is required, then discharging when the energy system requires additional energy. Unlike traditional generators that turn fuel into electricity, an energy storage system is used to move energy around. A few common applications for energy storage include moving energy use from a period of low consumption to a period of high consumption, storing renewable generation to be used at night, or storing grid power to be used during periods of grid outage. For an energy storage system to make economic sense, the value of providing this service to a facility or the electrical system must exceed the cost of the energy storage system. How can a consumer determine if an energy storage system makes sense for a facility? The answer often lies in the utility bill.