Title: SCED Look-Ahead Step 1: Pricing: Calculate Non-Binding Prices and Basepoints for Initial Research into SCED Look-Ahead and allow Consumers to have a Forward Price Projection (formerly "Calculate and Post Projected Non-Binding LMPs for the Next 15 Minutes")
Next Group:
Next Step:
Status: Approved on 12/12/2011
Effective Dates:


Date Gov Body Action Taken Next Steps
12/12/2011 BOARD Approved
12/01/2011 TAC Recommended for Approval ERCOT Board consideration of NPRR351
11/29/2011 PRS TAC consideration of NPRR351
11/17/2011 PRS Deferred/Tabled PRS consideration of NPRR351
11/03/2011 TAC Remanded PRS consideration of NPRR351
10/20/2011 PRS PRS Impact Analysis review
09/22/2011 PRS Deferred/Tabled PRS Impact Analysis review
08/18/2011 PRS Recommended for Approval PRS Impact Analysis review
08/04/2011 TAC Remanded PRS consideration of NPRR351
07/07/2011 Under Appeal TAC consideration of ERCOT Steel Mills appeal
06/23/2011 PRS Rejected
05/19/2011 PRS Deferred/Tabled PRS language consideration

Voting Record

Date Gov Body Motion Result
12/12/2011 BOARD To approve NPRR351 as recommended by TAC in the 12/1/11 TAC Report. Passed
12/01/2011 TAC To recommend approval of NPRR351 as recommended by PRS in the 11/29/11 PRS Report. Passed
11/29/2011 PRS To recommend a priority of 2012 and rank of 100, to forward NPRR351 to TAC, and to endorse the Business Case as set forth in the 9/20/11 Trefny-Crockett comments. Passed
11/17/2011 PRS To table NPRR351 until the 11/29/11 Special PRS meeting. Passed
11/03/2011 TAC To grant the 10/20/11 ERCOT Steel Mills appeal and to remand NPRR351 to PRS as revised by TAC; to encourage WMS and PRS to continue discussions with ERCOT on the details of the SCED Look-Ahead project through workshops, special meetings, or other means; to instruct PRS to vote on either recommending approval or rejecting NPRR351 by the January 2012 PRS meeting and to report back to TAC; and to request that ERCOT provide more information to PRS at the 11/17/11 PRS meeting (or prior to the next TAC meeting if the PRS meeting is too soon) about its intentions on how to actually implement this NPRR in regards to wind forecasts, wind base points, ramp rates, State Estimator inputs, Dynamic Ratings, binding constraints, LDLs and HDLs, and the disclosure of forecasted base points to operators and the market. Passed
10/20/2011 PRS To grant NPRR351 Urgent status Failed
09/22/2011 PRS To table NPRR351 for one month; to request that ERCOT prepare comments outlining the impacts associated with Option 2 (as defined in the 9/21/11 ERCOT comments) and provide examples; and to request that WMS review NPRR351 and provide input by the October 20, 2011 PRS meeting. Passed
08/18/2011 PRS To recommend approval of NPRR351 as revised by PRS for the sole purpose of ERCOT’s preparation of an Impact Analysis for PRS review. Passed
08/04/2011 TAC To grant the ERCOT Steel Mills appeal and remand NPRR351 to PRS; to direct PRS to work with ERCOT to resolve any questions needed to complete the Impact Analysis; to request that ERCOT perform an Impact Analysis; and to direct PRS to recommend action on NPRR351 to TAC after the completion of the Impact Analysis. Passed
06/23/2011 PRS To reject NPRR351. Passed
05/19/2011 PRS To table NPRR351 for one month. 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.


Status: Approved
Date Posted: Apr 13, 2011
Sponsor: WMS
Urgent: Yes
Sections: 6.3.2,
Description: Using the inputs specified in this Nodal Protocol Revision Request (NPRR), ERCOT will calculate prices and base points over the next hour, using an hour-long optimization instead of a five-minute optimization. These calculated prices and base points will initially be non-binding, although it is anticipated that these will become binding as Security-Constrained Economic Dispatch (SCED) Look-Ahead progresses in future phases. Not covered by this NPRR are the larger pieces of SCED Look-Ahead, like Real-Time commitment of generators and Load Resources (possibly replacing or eliminating the Non-Spinning Reserve (Non-Spin) product), Real-Time co-optimization of energy and Ancillary Services (including determining when the co-optimization occurs), whether to charge make-whole charges and to whom they should be charged to, and how these revisions will support the overall market design and Resource adequacy requirements.
Reason: ERCOT expects this NPRR will be the first step of a multi-phase implementation of SCED Look-Ahead, with the results of this NPRR primarily being used for research purposes to determine how to best calculate prices and base points for future periods. In addition, the ERCOT Steel Mills and at least one retailer have expressed a strong desire to use the results to make Real-Time decisions on how to consume power in Real-Time based on prices. Primarily, this will be used to determine the accuracy (and improve it, if possible) of the SCED Look-Ahead Real-Time Dispatch process. At issue will be whether the improved algorithm delivers better results than the current one. There are a number of areas to analyze, including: · The predictability of the wind generation over the next hour. · How near-term Load growth and generator Dispatch will create binding contingencies over the next hour. · What sort of uplift costs will be created by the process, if any, once it becomes binding.

Key Documents

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