Which ancillary service market directly benefits from the quick charge/discharge capabilities of an ESS?

The ancillary service market that directly benefits from the quick charge/discharge capabilities of an Energy Storage System (ESS) is frequency regulation. Frequency regulation involves rapidly adjusting power output to maintain the grid frequency within a narrow band around its nominal value. The fast response time of ESS allows them to quickly inject or absorb power in response to frequency deviations, providing precise and effective frequency regulation services. This rapid response is crucial for maintaining grid stability and preventing frequency imbalances. Other ancillary services, such as spinning reserves and non-spinning reserves, also benefit from the quick response of ESS, but frequency regulation is the service that most directly relies on this capability. The faster the ESS can respond to frequency changes, the more effectively it can contribute to frequency regulation and the greater the potential revenue it can generate in the frequency regulation market.