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Loss-of-Load Events

LOLEV. The number of events in which some system load is not served in a given year.

Definition by NERC

Source: 1

Loss-of-Load Events (LOLEV) is the number of events in which some system load is not served in a given year. A LOLEV can last for one hour or for several contiguous hours and can involve the loss of one or several hundred megawatts of load. TRE-ERCOT is the only Assessment Area to provide this metric in its regional assessment.

Last modified: 2025-06-20

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  1. NERC (2013). Probabilistic Assessment - Addendum to the 2012 Long-Term Reliability Assessment. https://www.nerc.com/comm/PC/PAWG%20DL/NERC_2012_Probabilistic_Assessment_Final.pdf ↩