December 22, 2008 ARC Event

December 22, 2008 ARC Event

Monday December 22nd 2008 22:25 EST through 22:50 EST the Midwest ISO invoked the ARC procedure due to 500 MW of generation not available per unit commitment plan and a 500 MW net schedule interchange obligation. Up to 81 percent of the available ARC operating reserves were utilized during this period to assist in correcting the imbalance. There were no ARS events initiated during the event.