Frequency response of a Battery Energy Storage System (BESS) refers to the ability of the BESS to provide active power output in response to a change in the frequency of the electrical grid. When the frequency of the grid deviates from its nominal frequency, it indicates that there is a mismatch between the supply and demand of power in the system. In order to maintain the stability and reliability of the grid, it is important to quickly restore the balance between supply and demand.

BESS can provide frequency response by adjusting their active power output in response to a frequency deviation. The BESS can be controlled by a droop characteristic, which defines the relationship between the frequency deviation and the active power output. The droop characteristic is a proportional relationship, where the amount of active power output is directly proportional to the amount of frequency deviation. When the frequency of the grid decreases (underfrequency), the BESS will increase its active power output in proportion to the amount of frequency deviation.

Conversely, when the frequency of the grid increases (overfrequency), the BESS will decrease its active power output in proportion to the amount of frequency deviation. This helps to restore the balance between supply and demand in the grid and maintain the stability and reliability of the system.

Frequency response is an important requirement for BESS to comply with grid codes and regulations. It helps to ensure the stability and reliability of the grid and allows for the integration of renewable energy sources and other distributed energy resources.

At Blake Clough Consulting, We have the capability to carry out grid code compliance studies for both onshore and offshore developers. Our services include studies that may be required to assist in achieving a grid connection, such as fault level studies input into the application, or constraint analysis to determine potential level of constraints for connection options.