1. Nodal RTM Settlement Timeline Snapshot Timing for Load and Gen Data (Follow-Up)
Mandy Bauld
COPS
November 10, 2009

2. Topic Refresher
Proposed Nodal settlement schedule will advance the capture of generation and load data for use in settlements by 1 day
Zonal Timeline for gen/load data capture for use in settlements:
Generation: Operating Day + 8, + 57, + 178
Load: Operating Day + 8, + 57, + 178
Nodal Timeline for gen/load data capture for use in settlements:
Generation: Operating Day + 7, + 56, + 177
Load: Operating Day + 7, + 56, + 177
The timelines for running settlement calculations which use Data Agg data and for posting the statements do not change
Raised to COPS as a matter of transparency and to ensure that ERCOT considered all impacts

3. COPS Request for Follow-Up
Summarize comments/questions received from COPS members
Summarize the pros and cons discussed at COPS 10/13
Recommendation for transparency to the process
Summarize other points of interest
Comment on early posting of Settlement Statements

4. COPS Feedback
Summarize any comments/questions received from COPS members since 10/13
None received to date

5. Pros / Cons
Pros
Cons
Allows for Data Agg validation (and backout/rerun if necessary) prior to use of the data in the “next step,” thus minimizing the risk of a back-out / rerun on all other settlement jobs
TDSP and ERCOT EPS meter data processing timeline loses 1 day
Splitting the RTM settlement into 3 modular jobs: (1) RTM settlement not dependant on Data Agg, (2) Data Agg, and (3) RTM settlement dependent on Data Agg, allows flexibility to run the batch jobs according to the schedule and timing that best accommodates all DAM, RTM, and Zonal batch jobs
NOIE data submittal processing timeline loses 1 day
Reduction in percentage of NIDR data available for RTM Initial settlement

6. Recommendation for Transparency
Describe this process in the COPS Market Guide
Be clear that this process is the “happy path” scenario
Caviat that if ERCOT experiences system issues the timeline may vary (e.g., batch running long or issues that result in a rerun of Data Agg later than scheduled)
If there is a need to change the methodology for the “regularly scheduled” timing of this process, it would go back to COPS through the COPS Market Guide revisions process

7. Other Points of Interest
TDSPs are planning to have AMS data to ERCOT by Op Day + 6, therefore the proposed schedule (Op Day + 7) would accommodate the expedited AMS submissions. The TDSP planned AMS data submission exceeds Protocol expectations of every 38 days, where data is typically not available at Initial Settlement.
The last Zonal Initial Settlement and the first RTM Initial Settlement would use the same load data

8. Early Posting
Current Nodal Protocols use “on” rather than “by” language
PR 9.2.2(1) “ERCOT shall make each Settlement Statement for a DAM available on the date specified on the Settlement Calendar for that DAM …”
PR 9.5.2(1) “ERCOT shall make each Settlement Statement for the RTM available on the date specified on the Settlement Calendar for that Operating Day…”
ERCOT sees value in having a predictable schedule
Early posting could have unexpected consequences on billing cycles. It is possible that a statement expected to hit the next billing cycle would end up on the current billing cycle, instead.
Stmt scheduled to post 11/7, but posts early on 11/6
Moves from the 11/19 invoice back to the 11/12 invoice
11/12 invoice is “heavy” and the 11/19 invoice is “light”

9. Appendix Slides from 10/13 COPS

10. Why the change?
Increased number of Operating Days to be processed in the settlement system on a daily basis and to be verified by business on business days
Zonal Initial, Final, True-Up*, Resettlement
Nodal DAM, DAM Resettlement
Nodal Initial, Final, True-Up*, Resettlement
*Zonal True-Ups should be complete prior to start of Nodal True-Ups and therefore these jobs should not compete
Need to minimize the risk of a back-out / rerun on all other settlement jobs
Zonal: Data Aggregation and Settlements run in one batch, no opportunity for modularized verification before proceeding to the “next step”
Nodal: Data Aggregation and multiple Settlements jobs run in separate batches, allowing data verification of each job before starting the “next step,” and reducing impact of a back-out/rerun when necessary
Need to reduce risk of posting statements and invoices late when verification identifies errors and a back-out/rerun is necessary

11. Nodal Schedule for Settlement Use of Meter Data
"Operating Day "
Zonal
Nodal
Initial
Final
True-Up
EPS Data Captured 8 57
178 7 56
177
Load Data Captured
Settlement batch using Gen & Load
Settlement Statement Posting 10 59
180

12. Assumed Impact to Market Participants
TDSP and ERCOT EPS meter data processing timeline loses 1 day
QSEs with load should recognize which day was the “cut-off” for purpose of ERCOT’s calculation of Real-Time Adjusted Meter Load (RTAML)