The Midcontinent Independent System Operator (MISO) recently included energy storage in its market portfolio for the first time.
The inclusion of Electric Storages Resources (ESRs) enables resources, such as batteries, pumped storage facilities and compressed air energy storage, to participate in MISO’s Energy and Operating Reserves Markets as supply or demand.
ESRs are flexible resources that can help reduce peak demands, manage congestion and provide backup power for major disruptions because they can respond quickly and switch between injection (discharge) and withdrawal (charge) modes, MISO said.
The near-term benefits of the new ESR model are modest due to the small volume of storage resources. However, the new model positions MISO ahead of the increased storage participation anticipated with higher penetration of renewables and distributed energy resources over the next five to 10 years, the ISO said.
In 2021, applications of energy storage projects surpassed wind power in MISO’s interconnection queue for the first time. Solar projects were the single highest category with nearly 44 gigawatts (GW) of projects, followed by about 12 GW of storage projects and about 9.1 GW of wind projects.
The Federal Energy Regulatory Commission (FERC) in 2016 issued a notice of proposed rulemaking that would require regional transmission organizations and independent system operators to revise their wholesale power tariffs to better remove barriers to RTO-run wholesale market participation by energy storage resources such as large battery systems.
In 2018, FERC, in Order 841, voted to remove barriers to the participation of electric storage resources in the capacity, energy and ancillary services markets operated by regional transmission organizations and independent system operators.
In October 2019, FERC approved compliance filings by the PJM Interconnection and the Southwest Power Pool in response to a landmark 2018 FERC order that adopted rules aimed at removing barriers to the participation of ESRs in wholesale power markets.