April 17, 2008 ARC Event

April 17, 2008 ARC Event

Thursday April 17, 2008 from 19:55 EST through 20:20 EST the Midwest ISO invoked the ARC procedure due to a 350 MW Net Schedule Interchange obligation change over a ten minute period created by schedule changes. Up to 85 percent of the available ARC operating reserves were utilized during this period to correct the imbalance. There were no ARS events during the ARC procedure.