August 04, 2008 ARC event

Saturday July 26th 2008 09:40 EST through 10:25 EST the Midwest ISO invoked the ARC procedure due to loss of generation for approximately 450 MW and a temporary capacity shortage when load increase faster than projected. Up to 68 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.