The Federal Energy Regulatory Commission approved the California ISO scarcity pricing mechanism with the directive that the ISO review the mechanism every three years. The review is to determine whether the mechanism is providing the intended price signals and incentives. The ISO has posted a report reviewing ancillary service scarcity events that occurred from 2017 to 2019.

The report is available on the ISO website at http://www.caiso.com/Documents/2017-2019_AS_Scarcity_Report_final.pdf.