SCR795

    Summary

    Title: Addition of Intra-Hour Wind Forecast to GTBD Calculation
    Next Group:
    Next Step:
    Status: Approved on 04/10/2018

    Action

    Date Gov Body Action Taken Next Steps
    04/10/2018 Board of Directors Approved
    03/22/2018 TAC Recommended for Approval Revision Request Consideration
    03/08/2018 PRS Recommended for Approval Revision Request Consideration
    02/08/2018 PRS Recommended for Approval Impact Analysis Consideration
    12/14/2017 PRS Deferred/Tabled Language Consideration

    Voting Record

    Date Gov Body Motion Result
    04/10/2018 Board of Directors approved SCR795 as recommended by TAC in the 3/22/18 TAC Report Passed
    03/22/2018 TAC to recommend approval of SCR795 as recommended by PRS in the 3/8/18 PRS Report Passed
    03/08/2018 PRS to endorse and forward to TAC the 2/8/18 PRS Report and the Impact Analysis for SCR795 with a recommended priority of 2018 and rank of 2200 Passed
    02/08/2018 PRS to recommend approval of SCR795 as submitted Passed
    12/14/2017 PRS to table SCR795 and refer the issue to ROS and WMS Passed

    Vote tallies here reflect individual votes, not the weight of the votes by market segment. Affirmative votes are not recorded in these vote tallies. For additional details on the voting record, please consult the Recommendation or Action Report, or the official vote tally if available, as posted in the key documents.

    Background

    Status: Approved
    Date Posted: 11/28/2017
    Sponsor: ERCOT
    Urgent: No
    Sections: 6.5.7.3
    Description: ERCOT is in the process of adding an intra-hour wind forecast. This System Change Request (SCR) updates the formula used by the Resource Limit Calculator to calculate the Generation To Be Dispatched (GTBD) value to include the addition of a predicted 5-minute wind ramp (PWRR). This PWRR will be calculated from the intra-hour wind forecast times five and a configurable factor to capture the forecasted 5-minute wind ramp. This addition would help Security-Constrained Economic Dispatch (SCED) take into account the potential 5-minute wind ramp in its 5-minute Base-Points and would take the burden off of Regulation to cover the 5-minute gain or loss of generation from variations in wind and instead dispatch this energy economically. This change will also aid reducing frequency recovery duration following events that occur during times with significant wind up and down ramps. Although there will be inherent forecast error in the intra-hour forecast, this change will give a better indication to SCED via GTBD of the level of wind generation that will be available in the next 5 minutes, as compared to the current assumption that the wind generation will persist at the same level as at the beginning of the 5-minute interval. Once ERCOT begins to receive the intra-hour wind forecast from its vendor(s), ERCOT will analyze the 5-minute out forecast performance and accuracy of projected wind generation ramp direction before the intra hour wind forecast component is activated in the GTBD formula.
    Reason: Market efficiencies or enhancements

    Key Documents