NPRR696  Price Correction Process Following a SCED Failure

The existing process for managing price corrections following a Security-Constrained Economic Dispatch (SCED) failure creates situations where pricing outcomes are uncertain and may not reflect market conditions. When ERCOT experiences a SCED failure, the last good price is used for Settlement for the period of time when SCED does not execute. Following the failure, SCED resumes execution but ERCOT continues to take the necessary manual actions specified in paragraph (3) of Section 6.5.9.2, Failure of the SCED Process. to stabilize the system. During this stabilization period, ERCOT may or may not correct prices depending on their determination of whether the prices were erroneous or not. This creates price uncertainty for Market Participants that are actively transacting in the market. In addition, the manual actions taken in paragraph (3) of Section 6.5.9.2 following the SCED failure can significantly influence the pricing outcomes and produce results which do not reflect market conditions. This Nodal Protocol Revision Request (NPRR) establishes a price correction policy which uses the last good price for Settlement until ERCOT no longer requires manual action to stabilize the system following a SCED failure. ERCOT provides notice to Market Participants of the occurrence of a SCED failure by declaring a Watch in accordance with paragraph (1) of Section 6.5.9.2. Once the system has stabilized following a SCED failure and ERCOT no longer requires manual intervention, ERCOT will cancel the Watch in accordance with paragraph (4) of Section 6.5.9.2. By correcting prices for Settlement Intervals corresponding to the active Watch period, Market Participants will have transparency to known prices which reflect the last good SCED execution.