EIM Participants

These resources are intended for EIM entities and participating generators that are directly involved in the Energy Imbalance Market. 

Business Practice Manuals

Business Practice Manuals contain implementation details through which the California ISO and market participants conduct business in accordance with the Tariff. The Business Practice Manual for Energy Imbalance Market contains information about all EIM entity types.


The Energy Imbalance Market is governed by the California ISO (ISO) FERC-approved Tariff. Each section or appendix of the tariff is maintained and updated independently according to effective dates of the FERC accepted tariff amendment


Integrate with the ISO full network model

The network model defines system parameters, price node and market scheduling limit mappings and planned network model updates.


EIM Resource Onboarding Procedure

This procedure helps EIM entities submit the required onboarding documentation for new participating and non-participating resources. The procedure also applies when a non-participating resource would like to become a participating resource.


Transmission customers of EIM entities

Our computer based training modules are for Transmission Customers of EIM Entities to learn about participation in the EIM, the real-time market, base schedules, system outages, metering and settlements. For Western EIM updates, subscribe to news releases and notices.

Transmission customers should contact their EIM entity for most questions. For all other questions, contact ISO customer service. Please refer to tips for asking questions for more guidance on how to identify the resource best suited to address inquires.

s. Section 29 of the ISO Tariff addresses the provisions related to the Energy Imbalance Market. Appendix B. 17 – 20 contains agreements related to EIM participation.

Regulatory Filings

All publicly available California ISO-authored filings and FERC orders are posted on the ISO website.

ISO Department of Market Monitoring

The ISO Department of Market Monitoring (DMM) keeps a close watch on the efficiency and competitiveness of the Energy Imbalance Market. Links to tariff provisions discussing DMM’s role and responsibilities and various DMM reports, presentations and tariff filings are available on the ISO website.

Learning center courses

Western Energy Imbalance Market training

Explore topics pertaining to the real-time energy imbalance market that enables participants to buy and sell energy when needed.