This document summarizes the Council’s assessment of the adequacy of the power supply for the 2021[1] and 2022 operating years (October through September). In 2011, the Council adopted the annual loss-of-load probability (LOLP) as the measure for power supply adequacy and set its maximum value at 5 percent. For a power supply to be deemed adequate, the likelihood (LOLP) of a shortfall (not necessarily an outage) occurring anytime in the year being examined cannot exceed 5 percent.
The Council, with help of the Resource Adequacy Advisory Committee, updated its resource and load data, examined all appropriate operating assumptions and ran the GENESYS model to produce the results shown in the charts and tables in this report.
Other adequacy metrics that measure the size of potential shortages, how often they occur and how long they last are also reported because they provide valuable information to planners as they consider resource expansion strategies.
The Council is currently in the process of enhancing its adequacy model (GENESYS), in particular the hourly hydroelectric system dispatch simulation, and expects to complete the work by September of 2018. In addition, the Council will initiate a process in the fall of 2017 to review its current adequacy standard. Council staff and RAAC members will be asked to review the viability of the current metric (LOLP) and threshold (5 percent). This review should consider similar efforts going on in other parts of the United States, namely through the IEEE Loss-of-Load-Expectation Working Group and the North American Electric Reliability Corporation (NERC).
[1] The Council’s annual adequacy assessment looks at the status of the power supply five years out, to ensure that sufficient time is available for mitigating actions, if needed. However, because of the retirement of two major coal plants in 2021, the Council wanted that year’s adequacy to be reassessed.
