September 15, 2014



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ISO and PacifiCorp Outline EIM Implementation Plans for October 1




California ISO and PacifiCorp outline energy imbalance market implementation plans for October 1.



Main Text

The energy imbalance market (EIM) has been tested in a market simulation environment since July and is now shifting to implementation.  During October, PacifiCorp's systems will interface with a parallel non-binding production environment at the ISO, which will use real-time data to perform optimization and issue advisory dispatches to PacifiCorp.  The parallel operating environment will give both organizations an accurate view of actual market and operating conditions and provide operators and customers with additional experience with EIM operation, optimization, data transfers, and advisory dispatches.  Binding dispatches, related financial settlements, and actual energy transfers between balancing authority areas will begin on November 1.


The decision to implement a parallel non-binding production environment is pending ISO governing board authorization later this week and final readiness assessment by the ISO and PacifiCorp management.  The memo to the board is available on the ISO website at


Both PacifiCorp and the ISO welcome the EIM as an innovative tool to better manage energy in the west, bringing both economic and reliability benefits to customers in the region.



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