Performance Monitoring

The Generation and Energy Storage Section (GESS) monitors and analyzes performance data of Generating Assets (GA) and Energy Storage Systems (ESS) in an effort to ensure that they are appropriately maintained and operated, and that electrical service to the customers is reliable. GESS staff evaluate both real-time and historical data.

Real-Time Data

GESS staff receive real-time information on GA and ESS outages through a database from the California Independent System Operator (CAISO) and daily reports from Generating Asset Owners (GAO) and Energy Storage System Owners (ESSOs).   

CAISO is a non-profit public organization in charge of a majority of California’s high-voltage wholesale power grid operation. It serves as a link between GA and ESS facilities and utility companies in balancing the supply and demand of electricity in the State. CAISO has a database called Outage Management System (OMS), which collects transmission and generation outage information submitted by GAs and ESSs and/or utility companies. GESS staff can access OMS to obtain real-time or historic information on outages throughout the State. 

GESS also receives daily status reports from GAOs and ESSOs for facilities with a capacity of 50 megawatts (MW) or greater. GAOs and ESSOs provide the status of each operational unit by 9:00 am every weekday. GESS staff compile and record all unit status information. If a unit is out of service or curtailed by more than 50 MW, a GESS engineer will contact the power plant for more outage information and may arrange for an on-site inspection.

• Find out more about the Daily-Status-Report.
• Find out more about the Outage Inspection program.

Historical Data

GESS staff collect, compile, and analyze historical performance data on jurisdictional facilities. The three main data sources come from the North American Electric Reliability Corporation (NERC) Generating Availability Data System (GADS), OMS, and information gathered during an outage inspection.   

NERC GADS is a group of databases used to collect, record, and retrieve operating information from GAs and ESSs in North America. The data is used to improve performance of electric generating and storage equipment and to support equipment reliability and availability analysis by GADS data users. GESS staff can access GADS to conduct performance analysis on jurisdictional facilities, reconcile information between GADS with other sources such as OMS, and monitor timely and accurate data submittal to NERC.  

Per General Order (GO) 167-C, Sections 9.3.2 to 9.3.4, all jurisdictional generators and energy storage systems must submit design, event and performance data to the NERC GADS database. Jurisdictional generators and energy storage system owners must sign a release form, permitting NERC to share the GADS data with the CPUC.

• Find out more about the NERC GADS Filing Requirements.

• Daily Status Report