August 29, 2014



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Energy Imbalance Market Benefits Metrics Technical Bulletin Posted




The California ISO has posted a technical bulletin outlining the EIM benefit metrics, which will be used after EIM Go-live.



Main Text

Throughout the development of the energy imbalance market (EIM), several studies have documented the economic and reliability benefits for western participants.  Following Go-live of EIM in October, the ISO will quantify these benefits using real market data.


The EIM will efficiently dispatch resources across multiple balancing authorities in real time to balance supply and demand, and is expected to reduce system costs, while also enhancing reliability.  With EIM operational in October, the ISO will quantify these benefits through a comparison of real market results with EIM to a business-as-usual case without EIM.  The benefits will include the following components:


More economical transfers between EIM balancing authorities, which may also help mitigate regional over generation or under generation risks

A larger and more diverse generation portfolio will be considered in the economic dispatch, seeking the lowest cost generation to balance the EIM footprint

Resources with EIM offers may be re-dispatched to reduce cost or reduce transmission congestion

Reduced flexible ramping requirements through more flexible ramping transfers between regions, thereby reducing overall procurement costs


The ISO will publish quarterly reports documenting the aggregated benefits to each balancing authority in EIM.  The first report will be published in the January-February 2015 timeframe.


The methodology for calculating the EIM benefits metrics was presented at the public Market Surveillance Committee meeting on August 22, 2014.  The ISO has documented the methodology in a technical bulletin, which is available on the ISO website at


More information on the Energy Imbalance Market stakeholder initiative is available at



For More Information Contact

Nan Liu at or at 916-608-5895


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