As fossil fuel generation is progressively replaced with intermittent and less predictable renewable energy generation to decarbonize the power system, Electrical energy storage (EES) technologies are increasingly required to address the supply-demand balance challenge over a wide range of timescales.
Energy storage systems play a major role in smoothing the fluctuation of new energy output power, improving new energy consumption, reducing the deviation of the power generation plan, and improving the safe operation stability of the power grid. Specific classification scenarios are shown in Figure 4.
In [ 86 ], the impact of an energy storage system’s capacity on the economy of the whole life cycle of the system was studied to minimize the total cost of the system, including grid power supply costs, photovoltaic power generation costs, and battery charging and discharging depreciation costs.
The power grid side connects the source and load ends to play the role of power transmission and distribution; The energy storage side obtains benefits by providing services such as peak cutting and valley filling, frequency, and amplitude modulation, etc.
In this case, the energy storage side connects the source and load ends, which needs to fully meet the demand for output storage on the power side and provide enough electricity to the load side, so a large enough energy storage capacity configuration is a must.
As can be seen in Table 3, for the power type and application time scale of energy storage, the current application of energy storage in the power grid mainly focuses on power frequency active regulation, especially in rapid frequency regulation, peak shaving and valley filling, and new energy grid-connected operation.