ISO Logo
October 10, 2019


Information Only


Legal and Regulatory

Market Operations

Section 43A.6.3 Report of Non-Resource Adequacy Capacity for September 2019


The California ISO Tariff section 43A.6.3 requires the ISO to publish a monthly report of market and non-market commitment of non-resource adequacy (RA) capacity. The September 2019 report is available at


The accompanying spreadsheet listing all of the instances for the month, including committed resources and non-RA capacity based on resource dispatches, is available at


The ISO had one exceptional dispatch of non-RA in the month of September 2019.


The report includes the following:

  • name of the resource;
  • utility service area and local capacity area (if applicable);
  • maximum non‑RA dispatched in response to the event (MW);
  • how capacity was procured (for example, by residual unit commitment or exceptional dispatch); and
  • reason the non‑RA capacity was dispatched (either through market optimization or exceptional dispatch).


The “maximum” non-RA capacity includes non-resource adequacy capacity, which includes capacity payment mechanism capacity, committed as a result of physically binding start-up instructions and incremental energy dispatches. Exceptionally dispatched non-RA capacity will be reported separately from in-market non‑resource adequacy capacity for each trading day. Exceptional dispatches for the purposes of testing will not be included. Maximum non resource adequacy capacity will not include any non‑RA capacity below the resource’s minimum operating level if the resource has sold any capacity below that level as resource adequacy capacity. When this occurs, the RA must offer obligation applies to the minimum operating level (PMin) available.


Market commitments and dispatches result from a security constrained optimization based on bids and self-schedules from all capacity (RA and non RA) that has submitted bids. The ISO may also issue exceptional dispatches to commit and dispatch resources, for which the ISO uses available information to select the most economic resources for exceptional dispatch that can meet the reliability need. This generally results in exceptional dispatches only of RA capacity.


Phillip Booker at

Engage with us!
isoball twitterball RSSball Facebookball YouTube
Daily Briefing
Sign up
Daily Briefing
ISO Today
ISO Today
Flex Alerts
Sign up
Flex Alerts

California Independent System Operator | P.O. Box 639014 | Folsom, CA 95630 | United States