Contact us
For additional information or to explore opportunities associated with your participation in the EIM please contact:
Don Fuller
(916) 608-7055
Peter Colussy
(916) 608-5850
Home > Participate > Western Energy Imbalance Market

Participate in the Western Energy Imbalance Market

The Western Energy Imbalance Market (EIM) provides reliability and renewable integration benefits to the West while also providing economic benefits to participants. It is an automated, real-time energy wholesale market that matches the lowest cost electricity supply with demand every 15 minutes and dispatches every five minutes. This flexibility provides more opportunities to integrate cleaner sources of energy, such as wind and solar, that may be produced in one area but needed in another.


The EIM is both scalable and flexible. Individual EIM entities can choose to participate at any time with relatively low entry costs and no risk of exit fees. While taking advantage of the market, entities still maintain control over their assets.

Four entities, plus the ISO are now participating: PacifiCorp, NV Energy, Puget Sound Energy, and Arizona Public Service. Portland General Electric, Idaho Power, Seattle City Light, Balancing Authority of Northern California/Sacramento Municipal Utility District, and Salt River Project will enter the EIM 2017-2020. Several other entities are exploring participation.

The following section outlines the steps for a balancing area to become an EIM entity.

Become an EIM entity

Advance preparation is key to successful entry into the EIM — we will help you through the process. Please see the below high-level steps from the initial cost/benefit analysis through implementation and participation in the energy imbalance market. As you begin your analysis, we will provide you information regarding benefits, implementation steps and costs.


Perform cost benefit analysis
A key step before deciding whether to participate as an EIM entity is determining the costs and benefits. This may involve performing a production cost benefits analysis that includes multiple scenarios, estimated implementation costs and benefits for the prospective entity, the ISO and other EIM entities. We will share information on estimating costs based on experience of other EIM participants. Below are some recent examples from others who have completed the benefit analysis.


Establish an implementation agreement
After you decide to proceed with participation, we will jointly establish an implementation agreement and file it with the Federal Energy Regulatory Commission (FERC). This agreement outlines the terms of our partnership to prepare for your participation. The agreement also outlines the schedule milestones and associated payments to the ISO for our costs for related system changes, software licenses and other configuration activities.

Here is a current list of EIM implementation agreements that you can use as examples.

Train for EIM
Together we will develop and deliver an organized training curriculum for your staff. Our experienced staff will train your in-house training or end-user staff through online and instructor led courses and workshops covering all aspects of EIM, including market design, market operations, scheduling and settlements. In the interim we recommend your staff take the below online introduction course.


Establish operating procedures
We will collaboratively develop operating procedures prior to implementation to ensure operational readiness. You will have the opportunity to practice with business process changes and exercise operational procedures during table top training scenarios and market simulation. Operating procedures must be established and training completed prior to the start of parallel operations.


Complete the implementation process
The implementation process takes approximately 18 months and includes the below activities, which often run in parallel.

Plan for implementation
Together we will develop a detailed project schedule outlining all the steps leading to the market simulation, parallel operations and full participation. At this point you should consider the following:

  • staffing and project roles to manage EIM preparations
  • IT and operations project implementations
  • whether or not to engage a third party to assist with systems development and integration
  • impact to open access transmission tariff (OATT) and potential stakeholder processes to adapt it
  • a participating resource strategy to determine which resources will participate in EIM through individual bids

Establish agreements and identify scheduling coordinator and participating resources
As an EIM entity, your organization must enter into contracts with the ISO. Likewise, all resources that plan to participate and provide bids must become an EIM participating resource by entering into standard contracts. Both your organization and participating resources will need to select scheduling coordinators, who will directly bid or self-schedule into EIM and handle the settlement process.

Integrate with the ISO full network model
We will work closely with you to accurately integrate your network model into the ISO full network model, which is essential for economic resource dispatching.  You will have an opportunity to test connectivity and see the market model prior to market simulation testing.

Implement metering
Your metering facilities and data reporting processes will need to comply with our standards and requirements. Meter data must be reported for all resources and loads located within your balancing authority area, with participating generator data at five-minute granularity. We will help you to understand our requirements, which can adapt to many existing metering installations. Metering requirements for EIM entities have been revised to minimize implementation costs.

Click here to go to the Metering page

Modify impacted systems
You will need to modify your operating and bid-to-bill systems associated with EIM participation to enable reliable ISO control and accurate settlements.  Affected systems include, but are not limited to, the energy management system, forecasting, scheduling, dispatch, outage management and settlements.

Perform testing
Together we will perform system integration, security and functional testing of all impacted systems and processes. During market simulations we test both the system and market interplay between the ISO and your participating resources under simulated market conditions. We will publish a market simulation test plan outlining scenarios, a timeline and expected actions prior to testing.

Certify readiness, conduct parallel operations and transition to binding EIM production
The ISO will work with you to develop an activation readiness plan that includes a “go-live” schedule, system activation steps, communication protocols and a robust support plan. We will jointly track progress and report preliminary results during market simulation and parallel operations. We will also assist with the certification to FERC that the market simulation and parallel operations have demonstrated that systems and operations personnel are ready to operate as anticipated.


Contact Us

ISO staff is here to assist you in every aspect of implementation. If you need additional information on participating in the EIM, please contact our representatives listed on the left side of this page. You can also refer to the Energy Imbalance Market Business Practice Manual for additional information on many topics mentioned above.