Spinning Reserve

Synchronized generation and ready to serve additional demand.

Also known as:  

Synchronized Reserve

Last Updated:  June 22, 2025

Version:  1.0.1

Generated:  November 06, 2025

Definition by NERC

Source:

Unloaded generation that is synchronized and ready to serve additional demand.

Definition by PJM

Source: p27, Revision 45

Synchronized Reserve is reserve capability that can be converted fully into energy or load that can be removed from the system within 10 minutes of the request from the PJM dispatcher and must be provided by equipment electrically synchronized to the system. Resources committed to the Synchronized Reserve product can meet the Synchronized Reserve, Contingency (Primary) Reserve Service and the 30-Minute Reserve Service simultaneously.