Comments on Straw proposal

1. Please provide a summary of your organization’s comments on the Planning Standards - Remedial Action Scheme (RAS) Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

CalWEA generally supports CAISO’s efforts simplifying the RAS design. However, the proposal guidelines could have significant impacts on the generation projects currently in the interconnection queue, in terms of the network upgrade requirements, the cost of both network upgrades and interconnection facilities, the timeline for interconnection, and the deliverability. CalWEA urges CAISO to fully investigate the impacts before moving forward with the proposal and provide the evaluation to the stakeholders.  

2. Provide your organization’s comments on the removal of redundant language in the RAS guidelines, as discussed in section 3.1:

CalWEA supports the proposal. 

3. Provide your organization’s comments on the proposed updates to the RAS guidelines, as described in section 3.2:

CalWEA is concerned about the implementation of the proposed guidelines on both the existing RAS and the new RAS identified in the generation interconnection process. Please clarify how the RAS designs would have to change if not compliant with the proposal. If CAISO is going to grandfather RAS designs already in place, please specify which ones will get such treatment. In addition, CalWEA has the following specific comments.

G-RAS3.A and G-RAS4.G are overlapping and may be reconciled into one. Dynamically arming and tripping could be allowed if it is fully automatic and completely mitigates reliability concerns such that the contingency conditions triggering the RAS need don’t need to be monitored in market operations.   

Using the PMAX to set tripping amount in G-RAS6 is too restrictive and compromises the effectiveness of the RAS. As long as the RAS is fully automatic and completely mitigates the reliability concerns, it could trip actual generation up to 1150 MW or 1400 MW.

G-RAS4.E is limiting the overloading facilities monitored by a RAS to no more than 1 substation beyond the first point of interconnection. This is too restrictive and not necessary since G-RAS3.B sets the threshold for effectiveness of the generator tripping. 

As a 10% effectiveness threshold is set in G-RAS3.B, CAISO should consider applying the same threshold in the generation interconnection process for assigning RAS cost responsibility.

CAISO should standardize the cost treatment of bridge RAS in G-RAS7. As the cost treatment may belong to a different stakeholder initiative, CAISO should clarify the current practice and open the topic to future stakeholder comments and enhancements.

4. Are the proposed planning guideline updates sufficiently clear for understanding? If not, which specific proposed guidelines or standards would need further clarifications?

Please refer to comments in No. 3. 

5. Do the proposed guideline and standard updates help in simplifying RAS design and implementation?

Please refer to comments in No. 3. CalWEA recommends that a more complicated RAS design be allowed as long as the RAS is fully automatic and completely mitigates the reliability concerns.

6. Do the proposed guideline and standard updates help address your concerns in implementing new RAS to connect new resources and/or to maintain transmission reliability? If not, what are the suggested enhancements?

Please refer to comments in No. 3. 

7. Do you have any further suggestions to the proposed guideline and standard updates?

Please refer to comments in No. 3. 

8. Provide any additional comments on the Planning Standards - Remedial Action Scheme Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

Please refer to comments in No. 3. 

1. Please provide a summary of your organization’s comments on the Planning Standards - Remedial Action Scheme (RAS) Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

PG&E appreciates the opportunity to provide its perspectives on the straw proposal and looks forward to working with the CAISO and other stakeholders through the Planning Standards - Remedial Action Scheme (RAS) Guidelines Update. 

In general, PG&E believes additional clarity in the proposal is necessary and that the RAS guidelines should attempt to keep RAS local to radial/semi-radial facilities and away from network flows which are difficult to predict.

PG&E also has the following question about the proposal and requests it be addressed in the revised straw proposal:

• Is generator auxiliary load/station service able to be tripped as part of a RAS?

If so, this could affect the generator tripping mechanism.  Tripping locations could become important if auxiliary load/station service cannot be tripped.  In general, PG&E recommends avoiding tripping auxiliary load/station service.

Please see below additional comments

2. Provide your organization’s comments on the removal of redundant language in the RAS guidelines, as discussed in section 3.1:

PG&E has no comments at this time.

3. Provide your organization’s comments on the proposed updates to the RAS guidelines, as described in section 3.2:

ISO G-RAS3

In the proposal for ISO G-RAS3, the CAISO recommends that “RAS should trip load and/or resources that have effectiveness factors greater than 10% on the constraints that need mitigation.”  PG&E believes a 10% dfax is too low and should be between 25%-50% to include projects that are more effective.

ISO G-RAS4

In ISO G-RAS4 Section A, the CAISO proposes that “RAS should have no more than 6 contingencies”.  PG&E believes 6 contingencies are too many given this proposal conflicts with monitoring less than 4 elements in ISO G-RAS4, Section B (see below).

In ISO G-RAS4 Section B, the CAISO recommends that “RAS should not be monitoring more than 4 elements.”  PG&E requests the CAISO define what is an element.  For example, outage detection could need to monitor up to four (4) circuit breakers for one branch outage.  Would this count as one element or four elements?

In ISO G-RAS4 Section E, the CAISO proposes that “RAS should only monitor overloading facilities no more than 1 substation beyond the first point of interconnection.” PG&E supports the concept of proposing simple and local RAS. However, as it is written, it appears to focus more on interconnection projects and there could be conditions that a RAS would be necessary other than interconnection projects.  Thus, PG&E recommends more general language be used.

In ISO G-RAS4 Section G, the CAISO proposal states “RAS should not include logics to…”  PG&E recommends the verbiage be modified to “RAS should strive to not include…,” because there could be situations that necessitate its inclusion. PG&E also believes there is a typographical error in the second paragraph where it refers to “above RAS standard” since G-RAS4 is a guideline.

ISO G-RAS6

In ISO G-RAS6, the straw proposal quotes the guideline (originally ISO SPS3) and proposes to maintain it as a guideline due to retirement outlook for Diablo Canyon Power Plant (DCPP) remains fluid at this time.  It is unclear what the P2 generation tripping limit is since P2 was not listed.  PG&E requests the CAISO in the revised straw proposal include what the P2 tripping limit is.

ISO G-RAS7

If G-RAS7 is intended as a temporary “bridge” until system reinforcements are placed into service, then PG&E recommends language be included in the guideline to enforce the long-term plan. In other words, a temporary RAS is allowed for bridging when there is commitment for a long-term plan.  There should be a time limit for temporary RAS.

4. Are the proposed planning guideline updates sufficiently clear for understanding? If not, which specific proposed guidelines or standards would need further clarifications?

Please see above comments.

5. Do the proposed guideline and standard updates help in simplifying RAS design and implementation?

PG&E has no comments at this time.

6. Do the proposed guideline and standard updates help address your concerns in implementing new RAS to connect new resources and/or to maintain transmission reliability? If not, what are the suggested enhancements?

PG&E has no comments at this time.

7. Do you have any further suggestions to the proposed guideline and standard updates?

PG&E has no comments at this time.

8. Provide any additional comments on the Planning Standards - Remedial Action Scheme Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

PG&E has no comments at this time.

1. Please provide a summary of your organization’s comments on the Planning Standards - Remedial Action Scheme (RAS) Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

REV Renewables (REV) appreciates ISO’s consideration to keep the scope of the work technology neutral in this latest proposal. We are generally supportive of the latest CAISO proposal. However, REV requests more explanation on CAISO’s thinking behind items such as the proposal to use ten percent effectiveness factors. In addition, REV would also like to request CAISO on providing implementation level details including potential timelines (e.g. Cluster 14 Phase 2, 2023-24 TPP, etc.) for the proposal. Further details around the expected potential impacts to the existing RAS or future RAS proposals identified in the latest TPP/GIP studies will be quite helpful as well.

2. Provide your organization’s comments on the removal of redundant language in the RAS guidelines, as discussed in section 3.1:

REV has no comment at this time. 

3. Provide your organization’s comments on the proposed updates to the RAS guidelines, as described in section 3.2:

REV has no comment at this time. 

4. Are the proposed planning guideline updates sufficiently clear for understanding? If not, which specific proposed guidelines or standards would need further clarifications?

REV requests that CAISO provide the rationale behind choosing 10% effectiveness factor. Also whether CAISO is planning to use the 10% cutoff for RAS cost allocation purposes in the interconnection process.  

5. Do the proposed guideline and standard updates help in simplifying RAS design and implementation?

REV has no comment at this time. 

6. Do the proposed guideline and standard updates help address your concerns in implementing new RAS to connect new resources and/or to maintain transmission reliability? If not, what are the suggested enhancements?

REV has no comment at this time. 

7. Do you have any further suggestions to the proposed guideline and standard updates?

REV has no comment at this time. 

8. Provide any additional comments on the Planning Standards - Remedial Action Scheme Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

REV has no comment at this time. 

1. Please provide a summary of your organization’s comments on the Planning Standards - Remedial Action Scheme (RAS) Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

None

2. Provide your organization’s comments on the removal of redundant language in the RAS guidelines, as discussed in section 3.1:

SDG&E agrees with the removal of redundant language in the RAS guidelines.  

3. Provide your organization’s comments on the proposed updates to the RAS guidelines, as described in section 3.2:

• In response to G-RAS3, SDG&E disagrees that resource optimization should only be a guideline. SDG&E believes this should be included as a standard (S-RAS) and apply to any New RAS that is proposed. 

• In response to G-RAS4, SDG&E disagrees that the design of each RAS to be simple and manageable should only be a guideline. Such specific requirements to the design of a RAS should be part of a standard and adhered to. SDG&E believes this should be included in the standard (S-RAS) and apply to any New RAS that is proposed. 

• SDG&E would also like to see the acceptable amount of monitored contingencies (P1-P7) reduced from 6 down to 4, which would coincide with the allowable number of system elements.  

• In response to G-RAS6, SDG&E disagrees that the design of each RAS to trip either 1150MW (P1) or 1400MW (P3-P7) should only be a guideline. Such specific requirements to the design of a RAS should be part of a standard and adhered to for all Newly Proposed RAS. 

While it is possible that these changes may affect existing RAS, these may be mitigated by grandfather exemptions for existing RAS and only applying these to RAS moving forward

4. Are the proposed planning guideline updates sufficiently clear for understanding? If not, which specific proposed guidelines or standards would need further clarifications?

While SDG&E disagrees with certain entrees into the G-RAS, the guidelines as laid out are sufficiently clear. (See comments above) 

5. Do the proposed guideline and standard updates help in simplifying RAS design and implementation?

SDG&E believes if items in our response to question 3 are resolved, then the standards and guidelines updates will help simplify RAS design and implementation. (See comments above) 

6. Do the proposed guideline and standard updates help address your concerns in implementing new RAS to connect new resources and/or to maintain transmission reliability? If not, what are the suggested enhancements?

• SDG&E believes if items in our response to question 3 are resolved, then the standards and guidelines updates will help address concerns in implementing new RAS. (See comments above) 

7. Do you have any further suggestions to the proposed guideline and standard updates?

None

8. Provide any additional comments on the Planning Standards - Remedial Action Scheme Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

SDG&E reiterates and refers to our previous comments and proposals that have not been captured so far. SDG&E is open to a call to discuss these if necessary.

1. Please provide a summary of your organization’s comments on the Planning Standards - Remedial Action Scheme (RAS) Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

In general, SCE is supportive of the direction to simplify RAS design while preserving reliability and harmonizing with the ISO market. SCE provides the below comments for CAISO consideration and clarification.

2. Provide your organization’s comments on the removal of redundant language in the RAS guidelines, as discussed in section 3.1:

SCE supports the proposed removal of redundant RAS language due to the incorporation of the NERC PRC-012 standard.     

3. Provide your organization’s comments on the proposed updates to the RAS guidelines, as described in section 3.2:

SCE agrees with establishing a minimum effectiveness factor guideline, though would prefer to see this above 10%. This is particularly important when coupled with the guidelines to arm the full capability of a facility (ISO G-RAS6) and not dynamically arm generation (ISO G-RAS4.G). Adding generation with very low effectiveness will quickly count against the 1150/1400 MW trip limits while providing minimal benefit on a thermal overload.

Another possible downside to keeping a RAS simple and manageable is where that simplification of RAS leads to additional complications elsewhere. ISO G-RAS3 dictates that RAS should not have a complex design that is conditioned on different flow levels, yet this would impede designing a RAS that can adapt to system conditions, such as planned outages. Due to the challenges in operating around RAS action while needing to take such outages, SCE has been adding this functionality to reduce the need for manual operator intervention. Making the RAS more manageable for the ISO market makes it less manageable for operators. Another potential negative consequence of this guideline would be to trip more resources than required, which is detrimental to system reliability 

ISO G-RAS3 states that Involuntary load tripping should not be included in RAS for high density load area(s), but it does not clarify which types of contingencies are in-scope. While SCE agrees that this is highly undesirable, it may make sense as either an interim bridging mitigation, or as a mitigation for a particularly low probability/high impact event and system infrastructure upgrades are prohibitively expensive.

4. Are the proposed planning guideline updates sufficiently clear for understanding? If not, which specific proposed guidelines or standards would need further clarifications?

SCE believes the proposed guidelines are generally clear, though would like to point out a few specific areas that could cause confusion, and requests the CAISO provide clarifications:

ISO G-RAS4.E states that “the RAS should only monitor overloading facilities no more than 1 substation beyond the first point of interconnection,” yet it is unclear if this references any overloaded facility or all relevant overloaded facilities. It is also not clear what point of interconnection is intended.

ISO G-RAS6 states that “these amounts should be based on the maximum capability of the generating facilities,” but the term maximum capability could mean multiple things. This could be the contractual POI limit in the generator interconnection agreement, the actual capability at the generator terminals at a given temperature, or even the sum of all possible generation in the example of co-located storage and solar PV projects.

The ISO G-RAS7 guideline provides some temporary flexibility when bridging for system reinforcements, but references “RAS requirements” in general. It is not clear if this is meant to cover both the guidelines and standards, or only one of these categories.
 

5. Do the proposed guideline and standard updates help in simplifying RAS design and implementation?

Given that the most stringent requirements around simplification are guidelines, it is not clear that the updates will significantly reduce RAS complexity. Historically, SCE has designed many complex RAS and CRAS to accommodate additional generation and reduce curtailment. This RAS initiative documents that this level of RAS complexity causes challenges with the ISO market, but it neither clarifies how the new generation could be accommodated in the absence of complex RAS, nor does it make the simplification criteria enforceable. As such, the new RAS guideline and standard update is not substantially different than the past criteria in the goal of keeping RAS simple and manageable.

6. Do the proposed guideline and standard updates help address your concerns in implementing new RAS to connect new resources and/or to maintain transmission reliability? If not, what are the suggested enhancements?

SCE appreciates the efforts that CAISO has put into understanding the impact of RAS on the market model and incorporating stakeholder feedback into the proposed guidelines and standards, but is concerned that much of the content will not be implemented due to the likely cost of physical upgrades or economic impact of congestion management. As such, SCE suggests that some guidelines, such as the simplifications needed for RAS to be compatible with the CAISO market and the 1150/1400 MW tripping limitations, be instead implemented as standards. Guidelines, and deviations from such, alone may not be sufficient evidence justifying the need for a project.

The updated RAS guidelines and standards should also indicate how they would be applied across existing RAS and RAS proposed for modification through existing reliability and/or generation interconnection studies in addition to new RAS.

7. Do you have any further suggestions to the proposed guideline and standard updates?

SCE has no further suggestions.

8. Provide any additional comments on the Planning Standards - Remedial Action Scheme Guidelines Update straw proposal and September 26, 2022 stakeholder call discussion:

SCE has no additional comments.