ERCOT Reliability and Operations Subcommittee Meeting Notes – 8/3

Grid Monitor – staff writer | Posted 08/06/2023

1.     Antitrust Admonition


2.     Agenda Review


3.     Approval of ROS Meeting Minutes (Possible Vote)

a.     June 8, 2023


3.5  Technical Advisory Committee (TAC) Update

b.     TAC approved ROS procedures and the revisions that had been sent from ROS.

c.     ERCOT gave an update on RTC with single model battery storage. They are starting the project and the target date is in 2026. TAC is working on a charter for the new RTCWG.

d.     TAC endorsed Option 5 for the San Antonio reliability project.


4.     ERCOT Reports

a.     Operations Report  

                                               i.     A question was asked about the 4 deployments of ECRS. This is covered in section 2.2 of the report. ERCOT has posted additional information on the WMWG meeting page for tomorrow.

                                             ii.     The unofficial ERCOT peak demand was 80,787 MW for the month of June on 6/27/2023 HE 18:00; this was 4,069 MW more than the previous record of 76,718 MW set on 6/23/2022 HE 17:00.

                                            iii.     A PVGR Generation Record of 13,086 MW was set on 06/25/2023 at 12:48.

                                            iv.     There were 5 frequency events.

                                              v.     There were 4 instances where ERCOT Contingency Reserve Service was deployed.

                                            vi.     2 OCN’s for the extreme hot weather with forecasted temperatures in the North Central and South Central weather zones. 1 AAN’s issued for possible future emergency condition.

                                           vii.     1 Watch for a projected reserve capacity shortage with no market solution.

                                         viii.     3 DC Tie Curtailment Notices due to a planned or unplanned outage, including 1 Notice for DC_R and 2 Notices for DC_L.

                                            ix.     There were 46 HRUC commitments.

                                              x.     There was 1 day of congestion on the Bearkat GTC, 28 days on the North Edinburg to Lobo GTC, 26 days on the Nelson Sharpe to Rio Hondo GTC, 11 days on the West Texas Export GTC, 14 days on the Valley Export GTC, and 9 days on the North to Houston GTC. There was no activity on the remaining GTCs during the month

b.     System Planning Report  

                                               i.     ERCOT is currently reviewing proposed transmission improvements with a total estimated cost of $609.30 million as of June 30, 2023.

                                             ii.     Transmission Projects endorsed in 2023 total $978.43million as of June 30, 2023.

                                            iii.     All projects (in engineering, routing, licensing, and construction) total approximately $12.469 billion as of February 1, 2023.

                                            iv.     Transmission Projects energized in 2023 total approximately $442 million (as of May 12, 2023).

c.     Generic Transmission Constraint (GTC) Update

                                               i.     EROCT presentation posted and given.

                                             ii.     ERCOT was asked about the ride-through requirements addressed by NOGRR245, and whether those changes will help alleviate the GTC’s once they are in place. ERCOT answered that this remains to be seen, pending the actual changes then they will have to incorporate related observation into study cases. This will be similar to the integration of Large Flexible Loads (LFL) because of the potential for those facilities to trip during voltage dip. The latest information on GTL’s (for west Texas) is posted to MIS.

d.     EMS Upgrade Project Update

                                               i.     ERCOT presentation posted and given. This should go live on November 15th.

                                             ii.     Market participants asked whether they need to do any testing. They will not need to do any testing.

                                            iii.     ERCOT was asked to provide information about what upgrades are included in the EMS upgrade and will provide additional information at PRS next week.


5.     ROS Revision Requests (Vote)

a.     Impact Analysis

                                               i.     NOGRR215, Limit Use of Remedial Action Schemes

1.     ROS recommended approval in March, but since has been discussing questions about which sections can be implemented more immediately and which require more time. ERCOT filed a revised IA and comments. The group discussed the implementation time frame.

2.     Endorsed and forwarded to TAC on the combo ballot

                                             ii.     NOGRR249, Communication of System Operating Limit Exceedances 

1.     Endorsed and forwarded to TAC on the combo ballot

                                            iii.     NOGRR250, Related to NPRR1171, Requirements for DGRs and DESRs on Circuits Subject to Load Shedding

1.     Endorsed and forwarded to TAC on the combo ballot

                                            iv.     RRGRR035, Related to NPRR1171, Requirements for DGRs and DESRs on Circuits Subject to Load Shedding

1.     Endorsed and forwarded to TAC on the combo ballot

                                              v.     RRGRR033, Related to NPRR1164, Black Start and Isochronous Control Capable Identification

1.     Endorsed and forwarded to TAC on the combo ballot

                                            vi.     PGRR105, Deliverability Criteria for DC Tie Imports

1.     This was tabled to allow discussion on whether/how this impacts the Southern Cross directives. ERCOT is still having internal discussions and expects to file comments, hopefully before the September ROS meeting.

b.     Language Review

                                               i.     PGRR109, Dynamic Model Review Process Improvement for Inverter-Based Resource (IBR) Modification

1.     ERCOT provided an overview of the PGRR. There are several on-going efforts to improve processes related to IBR’s. This revision introduces two new requirements to improve the accuracy of, and dynamic modeling processes for, IBR’s. The first change is for new IBR projects in the interconnections queue. All projects will go through a final round of model review process before commissioning, after synchronization. They purpose of this change is to rectify the as-planned, and as-built projects. The second requirement addresses existing IBR’s in operation, to put them through a review process if they are going to modify their control settings. This process is needed due to the unique characteristics of IBR’s. These are both addressing recommendations from the NERC Odessa Event reports.

2.     This has already been discussed at DWG, and was requested to be sent to IBRWG and PLWG.

3.     Some of the IBR folks asked why all types of units wouldn’t be put through this review process. In particular, it was pointed out that one thermal unit tripped off during the Odessa 2 Event. ERCOT acknowledged that this could be an option, however, they have been focused on IBR’s.

4.     Others pointed out that this could extend the interconnection timing. ERCOT did an impact analysis, and did not see an impact on the timeline since this is after part 2 of the interconnection process.

5.     ERCOT was asked how they will communicate whether the modifications will or will not be approved. They would notify a resource entity if their setting changes were not approved and then work with the entity to arrive at an acceptable solution.

6.     It was asked what type of modifications require review under this process. For example, if a system had a transformer fail and they have a spare would it be necessary to use 90-120 days review process before it would be possible to install the new transformer? The group discussed whether it would change the dynamic characteristics of the units or not.

7.     Tabled and referred to IBRWG and PLWG on the combo ballot

                                             ii.     PGRR110, Revision to Accommodate Steady-State Node-Breaker Modeling

1.     ERCOT filed this to make changes to steady state planning models. They are transitioning models and noticed some sections of the planning guides referring to node-breaker models that will no longer be relevant.

2.     Tabled and referred to SSWG on the combo ballot

                                            iii.     NOGRR255, High Resolution Data Requirements

1.     ERCOT provided a general update. SPWG discussed this revision and planned a meeting on 8/4/23 for specific discussion on this. It will also be discussed at the next IBRWG meeting. Additionally, NERC published new draft PRC2 and PRC28 updates, for new disturbance monitoring equipment standards for IBR’s.

2.     This is a lengthy NOGRR that is likely to receive a lot of input from SPWG due to the technical complexity. In particular, there are CIP and communication considerations that need to be reviewed. ROS leadership reached out to the ROS working groups to help determine appropriate referrals.

3.     Tabled and referred to IBRWG and SPWG


6.     Operations Working Group (OWG)

a.     Verbal update provided by OWG leadership.

                                               i.     They are not able to reach consensus on NOGRR245 and ask ROS to take it back up.

                                             ii.     Regarding NOGRR255 please email Andrew if you’d like to join the SPWG meeting tomorrow.

                                            iii.     Next meeting, they will go over the MTE list.

b.     NPRR1070, Planning Criteria for GTC Exit Solutions (OWG/PLWG) (Possible Vote)

c.     NOGRR245, Inverter-Based Resource (IBR) Ride-Through Requirements (OWG, DWG, IBRTF) (Possible Vote)

                                               i.     Since OWG, copious comments have been posted. For time’s sake ROS leadership did not allow all parties to speak about their comments, but asked ERCOT to address the comments that have been made.

                                             ii.     NextEra Energy Resources spoke to let people know about a procedural path forward with ERCOT modifications to the NOGRR and more comments to be filed. They suggested that it would be possible to work through the remaining issues and still be able to keep this moving on the time line for the October Board.

                                            iii.     ERCOT shared that they are open to considering ideas as long as we work toward clear direction. They spoke to issues that commenters raised. In particular, they wanted to be clear that they are not basing statements about the potential for uncontrolled loss of load on studies and models, they are basing those statements on actual events that have occurred.

                                            iv.     Other comments that ERCOT addressed highlighted the question of whether synchronous condensers and grid-forming inverters could be a solution. ERCOT’s position is that this is NOT an alternative to NOGRR245. They need all IBR’s to ride-through normal system disturbances. NOGRR245 is needed WITH some type of system strengthening project like the synchronous condensers that have been proposed. They see grid-forming as a new technology that will support the current trajectory of IBR build-out.

                                              v.     ERCOT recognized that type 1 and type 2 (about 2GW nameplate) have specific challenges and may require more innovative solutions. On average these produce about 340MW of power on the system. They think it might be possible to have a solution that looks like dynamic reactive resources or an ESR at those specific site locations to make up for the impact of the inverter’s inability to ride-through so that the system doesn’t see the loss. Overall, the scope of units that still don’t have a clear path represent 4-5GW of nameplate capacity on the system, representing output of 15-60% of that nameplate.

                                            vi.     ERCOT also addressed comments that suggested very specific carve-outs for the oldest of the type 3 wind farms that could allow them to be brought into compliance. ERCOT believes the small, specific carve-outs may be attainable if commenters want to propose specific language.

                                           vii.     Other comments suggested that if ERCOT could delay the timeline with regard to the phase angle jump and multi-fault ride-through capability to a later date, prioritizing other changes first, it could help. Not all models would need that extension, but for the OEM’s that need this, it would allow them to prioritize necessary upgrades.

                                         viii.     Through discussions with OEM’s ERCOT believes that most units would be able to comply with IEEE2800, even though some may need to do a retrofit. ERCOT believes that their requirements are reasonable, even if they need to consider extending the deadline for an additional year.

                                            ix.     ERCOT also spoke to the potential for unit retirements and a subsequent resource adequacy issue that some commenters have raised. They stated that they are sensitive to this risk as well, but consider the current risk for uncontrolled load shed to be a greater risk than the potential for future controlled load curtailment, if IBR’s make the commercial decision to come off the system.

                                              x.     ERCOT was asked about their time line. They think that pushing NOGRR245 out past the October Board would delay certainty for OEM’s and QSE’s.

                                            xi.     It was asked whether a workshop on the potential transmission or grid-forming solutions was appropriate. PLWG [really RPG – see below] is working on reviewing the current synchronous condenser proposal.

                                           xii.     Some QSE stakeholders disagree with ERCOT’s characterization that most IBR’s appear to have a viable solution. They still have significant concerns about being able to meet these requirements and time tables.

                                          xiii.     Transmission stakeholders that spoke and OPUC supported moving this revision forward.

                                          xiv.     The group discussed the possible paths forward, and whether it was better to have a special ROS meeting, or to grant urgency. Folks were encouraged to file comments well in advance of the next regular ROS meeting, at which urgency can be considered.


7.     System Protection Working Group (SPWG)

a.     Presentation posted and given by SPWG leadership.

b.     SPWG Leadership (Vote)

                                               i.     SPWG Chair:  Andrew Mattei, Brazos Electric Cooperative

                                             ii.     SPWG Vice Chair:  Mark McChesny, Oncor Electric Delivery


8.     Revision Requests Tabled at ROS (Possible Vote)

a.     PGRR073, Related to NPRR956, Designation of Providers of Transmission Additions




9.     Inverter Based Resources Task Force (IBRTF)

a.     Verbal updated provided by IBRWG leadership. They are reviewing the scope of the working group, and which items that were task force items should transition to the working group.

b.     They also had encouraged IBR’s to provide comments to NOGRR245, and many parties did so.


10.  Planning Working Group (PLWG)

a.     Presentation posted and given by PLWG leadership.

b.     NPRR1180, Inclusion of Forecasted Load in Planning Analyses (PLWG) (Possible Vote)

                                               i.     ERCOT is still working on comments to the NPRR.

c.     PGRR107, Related to NPRR1180, Inclusion of Forecasted Load in Planning Analyses (PLWG) (Possible Vote)

d.     PLWG was asked whether the synchronous condensers will be on the next PLWG agenda, and the statement from earlier in the meeting was corrected to say that this issue has been discussed at RPG. ERCOT has posted its assessment of the synchronous condensers on the public website. TSP’s are working on their related RPG submittals. There is not further discussion planned at RPG, aside from review of those applications.


11.  Steady State Working Group (SSWG)

a.     Verbal update provided by SSWG leadership.

b.     PGRR106, Clarify Projects Included in Transmission Project Information and Tracking (TPIT) Report (SSWG) (Possible Vote)

                                               i.     The group continues to work on language related to this revision.


12.  Combo ballot (Vote)

a.     Ballot passed.


13.  Other Business

a.     2024 Meeting Schedule

b.     Review Open Action Items List

                                               i.     Work to review these action items continues. There are a few that may be close to closing out, such as the ride-through one, once NOGRR245 is resolved. ROS leadership suggested that the RAS assignments can be closed since the group pass NOGRR215.

c.     No Report

                                               i.     Black Start Working Group (BSWG)

                                             ii.     Dynamics Working Group (DWG)

                                            iii.     Network Data Support Working Group (NDSWG)

                                            iv.     Operations Training Working Group (OTWG)

                                              v.     Performance Disturbance Compliance Working Group (PDCWG)

                                            vi.     Voltage Profile Working Group (VPWG)


14.  AdjournAgenda

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