The California ISO has an ancillary services scarcity pricing mechanism in place that is triggered when the ISO is unable to procure the target quantity of one or more ancillary services in the integrated forward market or real-time market runs.
From Feb. 15-16, 2019, ancillary service scarcities occurred in the 15-minute market run for the following regions, services and quantities:
|
Trade Date
|
Hour
Ending
|
Intervals
|
Ancillary
Service
|
Region
|
Shortfall
(MW)
|
Percentage of Requirement
|
|
Feb 15
|
1
|
4
|
Regulation Down
|
SP26_EXP
|
14.4
|
13.7%
|
|
Feb 16
|
12
|
1
|
Regulation Up
|
CAISO_EXP
|
1.1
|
0.2%
|
|
Feb 16
|
12
|
4
|
Regulation Up
|
CAISO_EXP
|
3.9
|
0.7%
|
|
Feb 16
|
15
|
4
|
Regulation Down
|
CAISO_EXP
|
7.5
|
1.2%
|
The ISO confirmed the scarcity event during its price correction process. The published ancillary services prices correctly reflect the approved administrative set of scarcity prices.
