11 Renewable Resource

Renewable Generation Curtailment

Figure 85 shows the monthly wind and solar VERs (variable energy resource) curtailment of economic or self-scheduled generation in RTD by reason: system wide conditions or local congestion. Figure 86 shows the monthly wind and solar VERs (variable energy resource) curtailment of economic or self-scheduled generation in RTD by resource type.

The curtailment jumped in March compared to February similar to last year, as is common during the shoulder season when renewable generation is high but loads stay low. Most curtailments continued to be solar.

Economic curtailment is defined as the resource’s dispatch upper limit minus its RTD schedule when the resource has an economic bid. Dispatch upper limit is the maximum level the resource can be dispatched to when various factors are taken into account such as economic bids, generation outages, ramping capacity, etc. Self-schedule curtailment is defined as the resource’s self-schedule minus its RTD schedule when RTD schedule is smaller than self-schedule. Note that when a VER resource is exceptionally dispatched, then exceptional dispatch curtailment is defined as the dispatch upper limit minus the exceptional dispatch value.

Figure 85: Renewable Curtailment by Reason

Figure 86: Renewable Curtailment by Resource Type