Comments on Straw proposal

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

ACP-California does not have any specific comments on the stakeholder call itself, other than to thank CAISO for its willingness to consider modifications to the Generation Deliverability Methodology through this current process and its willingness to continue to review potential changes as the system and the Resource Adequacy (RA) program evolve. Below, ACP-California also offers some comments on the specific elements of CAISO’s Straw Proposal.  

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

ACP-California generally supports the removal of the Secondary System Need (SSN) from generation interconnection deliverability studies, so long as the studies continue to be performed, and transmission approved to meet the same needs within the Transmission Planning Process (TPP). It will be critical for the CAISO to continue to study SSN conditions in the TPP to confirm that the SSN study conditions do not result in risk of resource shortages. While we recognize CAISO’s 2023 Summer Assessment indicated that there were less concerns around resource shortages during the SSN period, it will be critical to confirm this continues to be the case and to provide a venue for transmission to be approved to address needs during SSN conditions, if warranted. We therefore applaud CAISO to proposing to continue to study the SSN in the TPP and urge CAISO to provide clear summaries of the results of the SSN and any transmission that may be recommended for approval in the TPP to accommodate needs during SSN periods.

Additionally, we continue to believe that, as the CPUC transitions to Slide of Day, it may be appropriate for CAISO to conduct more studies of deliverability in different conditions. And we appreciate that CAISO has indicated a willingness to continue to evaluate updates to the generation deliverability methodology as the RA transition moves forward.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

ACP-California understands CAISO’s justification for continuing with the current methodology for determining dispatch levels in the generation deliverability methodology. And we support CAISO’s proposed approach at this time, given its willingness to continue to explore the appropriate dispatch levels for resources as system conditions evolve and as Slice of Day is implemented. ACP-California is especially interested in evaluating Off-Peak Deliverability Methodology assumptions and dispatch levels in the future.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

ACP-California supports CAISO’s proposal to increase the DFAX threshold from 5% to 10% for 500 kV line overload constraints. We appreciate CAISO being willing to consider and propose changes of this nature.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

ACP-California supports CAISO’s proposal on this topic. As discussed more in response to question #7, we greatly appreciate CAISO’s willingness to consider the new concept of “conditional deliverability.” We look forward to working with CAISO to develop more details on conditional deliverability and ensure that it meets the needs of generation developers who are contracting the delivery of their output to offtakers and need to have certainty, over the period of multiple years, with respect to their deliverability status.  

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

ACP-Calfornia does not have any comments on this topic at this time but looks forward to continuing to review and engage in this aspect of the initiative.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Delays in completing deliverability upgrades have been a significant and ongoing problem for generation developers building projects inside of the CAISO footprint. ACP-California appreciates CAISO’s willingness to seek to address these concerns in a variety of venues, including increasing transparency and consistency of information through the creation and continuation of the quarterly Transmission Development Forums (TDFs). While the TDFs have been very helpful, they have not resolved the issues that developers face when deliverability upgrades are delayed and their contracts are affected.

The solution that CAISO has offered in this initiative of providing “conditional deliverability,” in certain instances, could go a long way to helping address the issues that developers of experiencing due to delayed deliverability upgrades. But the details of how this proposal will be implemented will be critical to whether it is actually useful in mitigating the issues developers are experiencing. As was expressed on the stakeholder call, it will be crucial for developers to know, relatively early on in the interconnection process, which of their upgrades might be able to be delayed while the project could still secure conditional deliverability. It will also be critical for developers to have certainty that their “conditional deliverability” status can be maintained until such upgrades are complete and will not be withdrawn. Having this type of “multi-year” certainty will be paramount to making this proposal a true, even if only partial, solution to the challenges that developers are facing with respect to delays in completion of upgrades. Additionally, we encourage CAISO to not implement this proposal in a way that would require a new defined term in the tariff, as this approach would make this solution harder to incorporate into the contracting process. Instead, we would encourage CAISO to consider how such “conditional” deliverability status could be implemented through interconnection agreements or other forms/documentation, while still giving the underlying generation Full Capacity Deliverability Status (FCDS) or Partial Capacity Deliverability Status (FCDS), as appropriate. Finally, to help developers understand and comment on the viability of this proposal, we encourage CAISO to provide as much detail as possible on the process for securing conditional deliverability in the next iteration of the proposal and would be happy to work with CAISO on developing those details if it would be helpful. 

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

?AES Clean Energy appreciates the opportunity to submit comments on the CAISO’s generator deliverability methodology review stakeholder initiative.  Overall, the CAISO provides positive changes to the deliverability methodology, but lacks detail for stakeholders to appropriately understand the impacts of individual proposals. AES Clean Energy provides comments below regarding the CAISO’s straw proposals. 

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

AES Clean Energy believes the CAISO should further assess the market impacts of removing the secondary system need scenario (SSN) from the deliverability studies.  The SSN is typically studied during the transition period where gross load remains higher and solar production begins to drop off, or hours-ending (HE) 15-18 during the summer months. The CAISO rationalizes the removal of the SSN through its 2023 Summer Loads and Resource Assessment, which indicated a significantly lower risk of resource shortage for hours leading up to HE 19.  AES Clean Energy questions whether the 2023 Summer Loads and Resource Assessment is the best indicator for removing the SSN as the assessment assumption considered a high level of hydropower that is not typically received in California.  More importantly, the CAISO should consider the potential market outcomes of removing the SSN, particularly regarding congestion and curtailment.  AES Clean Energy believes that solar curtailment may be exacerbated. As market participants utilize the Production Tax Credits, they may become more tolerant of price changes for renewable energy credits.  This may potentially cause more solar curtailment during the SSN hours if too much generation is online causing congestion.  Therefore, the CAISO should fully consider any potential negative market impacts. 

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

AES Clean Energy has no comment at this time but reserves the right to comment in the future. 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

AES Clean Energy generally supports the proposal to increase the DFAX threshold for 500 kV line overload constraints from 5% to 10%.  AES Clean Energy agrees with the CAISO that 10% DFAX is a more practical threshold for consider generator impact on 500kV line overloads. 

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

AES Clean Energy is disappointed that the CAISO proposes no change to the study of N-2 contingencies in its deliverability studies.  However, AES Clean Energy generally supports the alternative approach to providing conditional deliverability for generators as they await N-2 contingencies to complete, if no cascading outages are identified.  AES Clean Energy seeks clarification on the new proposed “conditional deliverability.” Specifically, the CAISO should provide a definition and methodology for the identification of cascading outages.  Ideally, the methodology should consider the results of load flow analyses.  

Other questions that CAISO should consider include: 

• Will resources with conditional deliverability be able to provide resource adequacy in the market? 

• Will conditional deliverability be awarded to N-2 contingencies that are conditionally credible?  

• How does conditional deliverability differ from interim deliverability? 

• When will interconnection customers be notified that conditional deliverability will be received? 

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

AES Clean Energy seeks additional information regarding the current average cost of ADNUs and LDNUs in order to provide feedback on the three options proposed by the CAISO.  The three options include: (1) Raise the cost threshold in the Area Constraint guideline for ADC-C4 to $25 M in current dollars; (2) Raise the cost threshold in the Area Constraint guideline for ADC-C4 to $35 M in current dollars; and (3) Eliminate the Area Constraint guideline.  The CAISO should provide data on the average cost of assigned ADNUs.  This would help stakeholders and the CAISO identify the policy impact of either increasing or removing the constraint guideline. 

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

AES Clean Energy generally supports providing conditional deliverability status to projects experiencing delayed deliverability upgrades.  However, AES Clean Energy seeks clarification on the definition and treatment of conditional deliverability, as discussed in Question 5. 

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

The Bay Area Municipal Transmission group (BAMx)^[1] appreciates the opportunity to comment on the CAISO's Deliverability Assessment Methodology Straw Proposal ("Straw Proposal," hereafter) issued on August 22, 2023, and subsequently discussed during the stakeholder meeting on August 29, 2023.

BAMx supports several changes proposed by the CAISO in the Straw Proposal and believes they would allow significantly more renewable resources to be interconnected quickly, with fewer required transmission upgrades, without compromising the CAISO's ability to meet reliability requirements. However, BAMx urges the CAISO to make additional, comprehensive updates to better achieve this goal.

The table below provides a summary of BAMx’s response to each of the issues.

We look forward to working with the CAISO and other stakeholders to ensure a reliable and economical transmission infrastructure.

[1] BAMx consists of City of Palo Alto Utilities and City of Santa Clara, Silicon Valley Power.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

The deliverability test methodology currently studies two scenarios: one is the highest system need (HSN) scenario and the other is known as the secondary system need (SSN) under higher gross load conditions when solar is dropping off. The CAISO proposes to remove the study of the SSN from generation interconnection deliverability studies. However, the CAISO proposes continuing to perform the SSN study in the Transmission Planning Process (“TPP”) for at least a few years to identify emerging issues. BAMx supports removing the SSN study from the generation interconnection deliverability studies. Including the SSN study in the TPP for a few years as a screening tool is appropriate, but should not be the sole justification for policy-driven transmission projects. Instead, any SSN overloads identified in the TPP should be flagged for further analysis, including scrutiny of load, resource and dispatch assumptions affecting the analysis.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

BAMx agrees with CAISO that, “stressed but not extreme conditions should be assumed in the deliverability test studies.”[1] We have repeatedly seen the tremendous impact of the generator dispatch levels on the need for network upgrades to accommodate the resource portfolios. One such example is the impact of Offshore Wind (OSW) dispatch assumptions on viable transmission alternatives to meet deliverability requirements for the 2023-2024 Sensitivity Portfolio.[2] In particular, the CAISO assessment shows that significantly more transmission network upgrades are required when the OSW resources are modeled as 100% of installed capacity for HSN hours instead of 83% based on the most recent data. BAMx is under the impression that, typically a higher level of generation dispatch is modeled in the deliverability assessment due to concerns about congestion and/or renewable curtailments. In our opinion, such worries can be handled as part of a practical economic assessment to address potentially increasing levels of generation curtailments due to congestion. To address concerns that additional curtailment will unduly shift economic upgrade needs to the TPP, the curtailment impacts of a reformed deliverability test (i.e., whether storage enabled by reform will offset the need for additional curtailments) can be tested in a production simulation study in the Generation Interconnection Process (GIP).

BAMx believes that a more reasonable level of dispatch should be used, between the QC level and the arbitrary 20% exceedance currently assumed in the HSN studies. CAISO also should allow for reasonable redispatch to mitigate overloads, particularly for storage resources that can flexibly move from discharging to charging and vice-versa.

[1] Straw Proposal, p.13.

[2] CAISO, “20 Year Transmission Outlook and Approach to Offshore Wind ,” August 16, 2023, p.37.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

BAMx supports this element of the Straw Proposal. It is expected to be a more practical threshold for including the generators that significantly impact the 500 kV line overload constraint, while excluding generators that have an insignificant impact on the high capacity and low impedance 500 kV constraint.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

CAISO proposes providing “conditional” deliverability to resources waiting for the N-2-related deliverability upgrades to be completed, assuming they would not cause cascading outages. BAMx supports the conditional deliverability that would allow significantly more renewable resources to be interconnected quickly and counted towards meeting the States’ mid-term reliability goals. The TPL-001 standard is one of NERC’s Transmission System Planning Performance Requirements and does not apply to generation deliverability studies. The TPL requirements are not mandated to be met via a generation deliverability assessment process, and CAISO already ensures those are met as part of the TPP and GIP. BAMx continues to believe that the application of N-2 contingencies in the deliverability assessment studies is unneeded and excessive. While any N-2 contingency must be addressed per the TPL standards, it is not the case that “all N-2 contingencies need to be managed simultaneously” by the limited set of resources included in the deliverability studies. CAISO has access to a wide array of resources across a broad geographic area. CAISO also has the ability to advocate for increases to the  Planning Reserve Margin if its studies show that the current PRM results in insufficient capacity from the entire CAISO BAA to address common mode N-2 contingencies.

BAMx believes that not having some of the Area Delivery Network Upgrades (ADNU), especially those triggered by N-2 contingencies, will not threaten the transmission system's reliable operation in the near term or the long term. Although N-2 constraints have not driven the majority of ADNUs, we know that there are constraints like Lugo–Victor–Kramer Corridor on-peak deliverability constraints identified in the 2022-2023 Transmission Planning Process that are exclusively driven by P7 contingencies. In some cases, the lack of transmission upgrades may cause more congestion and/or renewable curtailments, but in our opinion, that can be handled as part of the economic assessment.

In summary, BAMx urges the CAISO to perform more analysis of the cost savings and reliability impacts of excluding N-2 contingencies from the generator deliverability assessment.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

No comments at this time.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

BAMx supports this element of the Straw Proposal as it would allow significantly more renewable resources to be interconnected quickly and counted towards meeting the States’ mid-term reliability goals. BAMx also believes that the timely interconnection of resources, such as battery storage at appropriate locations, would increase reliability and help utilize the existing transmission more effectively to accommodate additional renewable resources.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

The California Community Choice Association (CalCCA) appreciates the opportunity to provide the following comments in response to the California Independent System Operator’s (CAISO) Deliverability Assessment Methodology Straw Proposal.  CalCCA is encouraged by some elements of the proposal but suggests that the CAISO take a more aggressive approach to unlocking additional deliverability considering the urgent need to bring new resource adequacy (RA) capacity online to meet load-serving entities’ (LSEs) RA compliance obligations, integrated resource planning (IRP) compliance obligations, and the state’s clean energy policies.  Reliability is a key tenant of the process, but CalCCA encourages the CAISO to consider the various other “reliability-based” studies that include stressed system conditions such as the Generator Interconnection Process (GIP) and the annual Transmission Planning Process (TPP).  Both of these study processes address stressed system conditions and associated reliability pursuant to North American Electric Reliability Corporation (NERC) Reliability criteria and are better suited to address large-scale upgrades. 

The deliverability methodology is used in the generator interconnection study process to assign Full Capacity Deliverability Status (FCDS) enabling the specific generator to provide RA and to realize the associated revenue stream; a revenue stream that in most cases is required by the off-taker or to make the project economically viable.  CalCCA understands that during stressed system conditions, not all supply is coming from RA resources and that in some cases RA resources are operating above their Net Qualifying Capacity (NQC) level.  Applying less stringent criteria will enable a greater volume of FCDS to be allocated without unduly jeopardizing reliability. CalCCA provides the following recommendations, described in more detail in sections 2-7 below:

• Eliminate the Secondary System Need (SSN) study;
• Limit RA resource dispatch levels to their NQC;
• Perform a limited-scope analysis looking at the potential benefits and reliability impacts of limiting existing RA resources to their NQC to determine the benefit of increased allocation of FCDS.
• Raise the DFAX from five percent to ten percent for 500 kilovolt (kV) lines and expand this change to include transformers (500 kV high side banks);

Perform a limited-scope analysis to understand the benefit versus the risk of eliminating N-2 contingency criteria; and

• Provide more information regarding how conditionally deliverable megawatts (MW) will be counted towards RA plan accounting.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

CalCCA agrees with CAISO that the elimination of the SSN study is a prudent step that may increase the volume of deliverability allocations.  Considering the high level of energy storage projects entering the interconnection queue as well as proposed photovoltaic facility augmentation with storage the SSN is likely to diminish over a relatively short time.  This, coupled with increasing the storage values to 50 percent in the studies from 30 percent, will further mitigate the SSN.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

CalCCA suggests that the dispatch levels for RA resources be set at their NQC levels and no higher.  The purpose of the deliverability study is to qualify/validate resource volumes that can be used for RA accounting purposes.  While it may be possible for some resources (wind and solar) to achieve an output in excess of their NQC, assuming this in the deliverability study precludes other projects within the area to be allocated capacity.  At present, we have a shortfall of RA-qualified resources.  By limiting those existing RA resources to amounts proven to be available (NQC) and no higher, additional projects will be allocated capacity that can be available to LSEs.

It would be very informative if the CAISO could perform a limited scope analysis looking at the potential benefits of limiting existing RA resources to their NQC to determine the benefit of increased allocation of FCDS. 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

CalCCA agrees with the CAISO and BAMx that raising the DFAX from five percent to ten percent for 500 kV lines provides a more practical threshold.  Further, CalCCA suggests that this be expanded to include transformers (500 kV high side banks) that may be experiencing overloading as these are generally key elements in delivering energy from transmission-constrained areas to load centers.  This change coupled with more aggressive “policy upgrades” coming out of the TPP will ultimately increase overall deliverability and availability of RA. 

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

CalCCA is encouraged by the CAISO’s effort related to conditional deliverability, described in section 6 below, but suggests that for Generator deliverability objectives here, including N-2 is redundant as it is already addressed in the long-range TPP as well as the GIP.

NERC reliability criteria are met via the TPP whereas the GIDAP (Generator Interconnection and Deliverability Process) is an indication where upgrades may be needed based on aggressive development efforts.  N-2 is an extreme situation for the transmission system with low probability.  Including N-2 Contingencies unnecessarily limits the allocation of FCDS, which compromises the development of mostly RPS resources.  As we have seen in recent TPP, the planning process will identify and implement new transmission as needed to meet state policy, which will address N-2 issues.

FCDS assigned via the GIDAP has a key role in the development of renewables and other needed resources.  Less restrictive criteria for the deliverability methodology are acceptable because the more restrictive criteria are considered in other CAISO studies.  As noted above under section 2, a limited scope analysis would be very informative to understand the benefit versus the risk of eliminating N-2 contingency criteria.  

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

CalCCA has not formulated specific input for the CAISO regarding ADNU/LDNU Guidelines as of the date of these comments.  We look forward to the CAISO’s proposal on this matter and will assess and provide comments as needed.   

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

CalCCA supports any measure by the CAISO to assign interim or conditional deliverability. RA capacity is extremely scarce and assigning conditional deliverability while upgrades are in progress could expand the RA supply stack at a time when it is much needed. However, more information is needed to understand how these conditionally deliverable MW will be counted towards RA plan accounting as well as IRP compliance obligations.  Additionally, it is critical that tariff provisions and policies surrounding “conditionality” be clear and allow for clean contracting for RA.  CCAs generally require certainty around the deliverability status of projects before signing Power Purchase Agreements (PPAs) so they are assured the projects can count towards their RA and IRP obligations. It would be unacceptable for an LSE to contract for RA that is conditional, to have it somehow become unavailable for RA or IRP accounting in the future.

CalCCA provides the following suggestions and comments:

1. Conditional deliverability should be based on a counterfactual calculation of the total deliverability available without N-2 contingencies or PTO delays.
   1. Unlike interim deliverability, conditional deliverability should not be based on the amount of existing deliverability available before an ADNU is executed—it should be based on the counterfactual scenario.
2. Conditional deliverability should be reassessed for all queued projects at each GIDAP, allowing projects that may have received partial capacity deliverability status (PCDS) from conditional deliverability to increase depending on TPP upgrades or updated PTO schedules.
3. Unlike interim deliverability, conditional deliverability should be offered immediately and notification should not be dependent on a project’s commercial operation date (COD). This would make conditional deliverability contractable.
4. Any N-2 projects that require approval to unlock conditional deliverability should be clearly identified in the GIDAP results for a project.  The PTO timing assumptions for a project for determining delay-related conditional deliverability should also be very visible and locked in after the interconnection agreement is signed.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

The Public Advocates Office at the California Public Utilities Commission (Cal Advocates) provides these comments on the California Independent System Operator’s (CAISO) August 29, 2023 presentation on its Generation Deliverability Assessment Methodology Revisions - Straw Proposal.  Cal Advocates is an independent consumer advocate with a mandate to obtain the lowest possible rates for utility services, consistent with reliable and safe service levels, and the state’s environmental goals.[1]

Cal Advocates appreciates CAISO’s response to its comments on the existing N-2 contingency study considerations in the CAISO Deliverability Assessment Methodology Revisions - Straw Proposal.  CAISO’s proposed revision in response to comments would provide interim deliverability to generating resources while waiting for the completion of related N-2 deliverability upgrades.[2]^,[3]  As the CAISO states this award would only be given in cases where reliability concerns do not exist.[4]

Cal Advocates mentioned in our prior comments on the Issue Paper that Southwest Power Pool (SPP) considers N-2 contingencies in its deliverability studies only where it is deemed necessary.[5]  Midcontinent Independent System Operator (MISO) only considers P0 and P1[6] (normal and N-1) contingencies in its deliverability studies.[7]  A current MISO employee confirmed that “deliverability is performed by creating a stressed dispatch case.  Adding more complex contingencies are deemed not credible and therefore only N-1 is performed for deliverability.  Only using N-1 aligns with operation where the market is only looking at N-1.”[8]  

Cal Advocates supports CAISO’s proposal of providing “conditional” deliverability for resources waiting for the completion of N-2-related deliverability upgrades.  This step will assist with timely generation interconnections that are needed to meet the state’s clean energy targets.  Cal Advocates remains concerned that applying “conditional” deliverability could still create unnecessary barriers to integrating renewables and may result in unnecessary costs to CAISO ratepayers.  Thus, Cal Advocates recommends CAISO consider the following additional steps to its generation deliverability studies for future discussion in this stakeholder process.

1. CAISO identifies N-2 contingencies that have cascading outage risks or are always considered credible.
2. CAISO evaluates the consequences of not pursuing proposed projects based on N-2 contingencies that would not result in cascading outages.
3. Based on the N-2 study findings with these additional steps, CAISO provides generation deliverability with no conditions where reliability concerns do not exist or cannot be confirmed. 

[1] Cal. Public Util. Code, § 309.5.

[2] CAISO Deliverability Assessment Methodology Revisions Straw Proposal, CAISO, August 22, 2023 at p. 18.

[3] N-2 also referred to as P7 and stands for multiple contingencies such loss of: 1.)  two adjacent (vertically or horizontally) circuits on a common structure; or 2.)  loss of a direct current (DC) line.  This is the most extreme steady and stability test category per NERC TPL-005 Transmission System Planning Performance Requirements.

[4] CAISO Deliverability Assessment Methodology Revisions Straw Proposal, CAISO, August 22, 2023 at p. 18.

[5] Southwest Power Pool Generator Interconnection Manual (DISIS Manual), SPP  Generation Interconnection Department, January 2023 (SPP Manual) at p. 29.

[6] P1 standards for a single contingency such as loss of one of the following: 1.) Generator; 2.) Transmission Circuit; 3.) Transformer; 4.) Shunt Device; or 5.) Single Pole of a DC line.

[7] MISO Generation Interconnection Business Practice Manual BPM-015 r25 (MISO PBM), March 1, 2023 at p. 121.

[8] Email to Public Advocates Office staff from Ryan Westphal, Senior Manager – Resource Utilization, MISO Energy, June 15, 2023 at 12:37 pm.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

Cal Advocates requests a discussion on Pacific Gas and Electric Company’s (PG&E) proposal for future N-2 contingencies studies provided in its comments on the Generation Deliverability Assessment Methodology Review Issue Paper.  The Straw Proposal and the stakeholder meeting on August 29, 2023 did not directly address PG&E’s proposal.  PG&E suggested CAISO use a “stochastic analysis to evaluate the possibilities for all active N-2 contingencies, and determine which contingencies are more likely to happen depending on its risk zone.”[1]

Cal Advocates supports PG&E’s recommendation that CAISO determine the N-2 contingencies that are likely to happen.  Cal Advocates also recommends that CAISO put no conditions on deliverability determinations for interconnecting generation where the probability of an N-2 contingency is low, and where it would not result in a cascading outage.  This would reduce unnecessary barriers to renewable integration and minimize CAISO ratepayer costs.

[1] Pacific Gas and Electric Company’s comments on the Generation Deliverability Assessment Methodology Review, June 22, 2023 at p. 2.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

CalWEA greatly appreciates CAISO’s thoughtful consideration of stakeholders’ input on these arcane, but critically important, issues and its willingness to propose meaningful reforms in several areas.  These reforms could enable a significant number of projects to accelerate their grid interconnections and help load-serving entities meet their near-term reliability and clean-energy requirements while enhancing competition and thus reducing costs.

CalWEA remains concerned, however, that the stakeholder call did not allow sufficient time to discuss some of the fundamental issues raised in the Joint Proposed Framework for Discussion, submitted on June 22, 2023, by CalWEA, BAMx and CESA. Further reforms could far more substantially promote cost, reliability, and other public policy goals. CalWEA raises some of these issues in these comments.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

CalWEA appreciates and supports CAISO’s proposal to eliminate the Secondary System Need (“SSN”) test from the deliverability studies.  As stated in the Joint Proposed Framework, the SSN test focuses mainly on the local curtailment of supply resources, which does not translate to a lack of system reliability due to capacity shortage (which is the main purpose of CAISO’s deliverability test studies for the purpose of RA capacity eligibility). Therefore, it is appropriate that CAISO join PJM and MISO in using only one test, equivalent to HSN, aimed at the high system need period when testing for generation capacity designation for RA.  

We also agree with CAISO, however, that the elimination of the SSN test is justified on reliability grounds because, while “resource shortage conditions do occur during the SSN study period” (hours ending 15 to 18), the CAISO’s Summer Assessment studies show a “decreasing risk of resource shortages during the SSN study period.”  CalWEA notes that CAISO at one time included HE 18 in the High System Need (HSN) window but moved that hour into the SSN window in 2022.  CalWEA believes that HE 18 belongs in the HSN window and, in that case, the SSN window would be shown to be even less risky.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

First, the Straw Proposal appears to minimize the dispatch level issue as being one “primarily associated with wind generation study values due to the characteristics of the wind resources.”  This argument only becomes true once the SSN test is eliminated; otherwise, solar projects would also be greatly and inappropriately impacted from a severe over-representation of resource capacity.  Moreover, while it is true that the greatest disparity between the CPUC’s QC values and the CAISO’s arbitrary exceedance levels (used as CAISO’s dispatch assumption) exists for wind resources in the HSN period, the impacts are felt by all other types of resource capacity seeking access to the grid and therefore bears on the cost-effective achievement of the state’s clean energy goals.  For example, if CAISO plans for offshore wind at an 83% exceedance level (as CAISO is planning to assume in its 20-year Transmission Outlook for HSN hours), rather than its ELCC value (currently estimated at approximately 50%), offshore wind will require many gigawatts of Transmission Planning Deliverability (TPD) capacity that would otherwise be available for storage resources that would help integrate that wind and other variable energy resources by absorbing production above QC levels and dispatching when the system needs it and VER production is below QC levels. 

Second, CAISO’s response to using the CPUC’s QC values as the dispatch assumption for wind is completely centered around curtailment concerns (using CalWEA’s simple two-bus conceptual example as if it were a proxy for the complex grid).  Here again, however, if transmission capacity is not reserved above QC levels, that capacity will be available for storage resources that will help to integrate wind.

Nevertheless, we are encouraged that the Straw Proposal indicates that CAISO will “continue to monitor the CPUC’s development of NQC values and evaluate the need for further updates to its deliverability methodology.”  We note that CPUC staff have already issued preliminary 24-hourly values and we encourage CAISO to begin contemplating how it will use these values in its dispatch assumptions. For example, for each resource, CAISO could use the highest hourly QC value in the HSN window as its dispatch value. 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

CalWEA strongly supports and appreciates the proposal to raise the 5% DFAX threshold for 500 kV line overload constraints to 10%. We also encourage CAISO to consider extending the 10% threshold to 500/230 kV transformers if the constraint is from the transformer’s high to low side.  

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

CAISO continues to incorrectly link its deliverability studies to various NERC/WECC requirements and to use that linkage to justify studying P7.1 contingencies (N-2 outages of double-circuit towers).[1]  A strong indication that there is no such linkage is the fact that CAISO has previously narrowed the scope of N-2 outages that it considers in its deliverability studies and now studies only P7.1 contingencies.  While NERC/WECC require all credible N-2 contingencies to be studied as part of reliability studies performed in the interconnection process, there are no such requirements for deliverability studies.  As the Joint Framework Proponents explained in footnote 3 of their June 22, 2023, comments: “The TPL requirements are not mandated to be met via a generation deliverability assessment process, and CAISO already ensures those are met as part of the [Transmission Planning Process (TPP)] and [Generation Interconnection Process].” 

CAISO also expresses concern that “discontinuation of the n-2 contingency studies [in the deliverability test] would lead to sub-optimal results that would need to be addressed and resolved – albeit less effectively and less timely – in the [TPP].”  On the stakeholder call, CAISO indicated that the deliverability study should drive transmission needs so that the transmission requirements of a project do not get ignored in the procurement process and that addressing those needs in the TPP would be reactionary. These concerns are misplaced.

First, the N-2 criterion that CAISO currently applies in its deliverability test is extraordinarily conservative and triggers a need for upgrades that would not be triggered in TPP studies, resulting in the unreasonable denial of the full capacity deliverability (FCD) status required for RA eligibility.  The P7.1 criterion in the deliverability methodology tests a resource under an N-2 condition that applies to that resource, which by itself is an extreme assumption, but, in practice, effectively applies to a combination of RA resources at once, which collectively have passed hundreds of different and simultaneous N-2 deliverability tests at various grid locations – an inconceivable circumstance that would never be considered in reliability studies.

Second, reliability upgrades should be separately addressed in the reliability portion of interconnection studies, which are subject to NERC standards.  If CAISO is concerned that insufficient reliability upgrades will be identified there, additional reliability test scenarios could be added to the generation interconnection study process.

For all these reasons – and the major reliability, environmental, and ratepayer benefits that relaxing the deliverability methodology would bring, CalWEA continues to encourage CAISO to eliminate the N-2 criterion from the deliverability study.  Alternatively, as a compromise, CAISO could adopt, across the board, the much lower N-2 standard being proposed under its “conditional deliverability” proposal as discussed in response to question 7 below.

CalWEA underscores that our proposed reforms are intended only for CAISO’s resource deliverability test studies in GIDAP and are not intended to question CAISO’s deliverability study methodology and assumptions used in the TPP process.

[1] From p. 15 of the Straw Proposal: “The ISO on-peak deliverability assessment methodology currently includes n-1 and n-2 contingencies. NERC Reliability Standard FAC 002, Facility   Interconnection Studies, is an applicable reliability standard for generation interconnection studies.  It requires steady-state, short-circuit, and dynamics studies as necessary to evaluate system performance under both normal and contingency conditions in accordance with Reliability Standard TPL-001. NERC Reliability Standard TPL-001 requires common mode n-2 contingency analysis.” 

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

CalWEA supports eliminating the Area Constraint guideline ADC-C4. The cost threshold for projects that qualify for ADNUs under ADC-C4 should be raised to at least $50 million, which is already covered by ADC-C3; therefore, ADC-C4 is unnecessary. This change will enable developers to have more control over less-expensive upgrades that are needed to achieve deliverability status.  We note, however, that eliminating or relaxing the N-2 criterion in deliverability studies will result in many fewer ADNU and LDNU upgrades.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

The CAISO’s “conditional deliverability” (“CD”) proposal is a significant step in the right direction, particularly because it implicitly acknowledges that there are no applicable NERC standards for the deliverability portion of the GIDAP studies, contrary to statements in the Straw Proposal such as that referenced in question 5, above. Under its CD proposal, CAISO proposes to apply reliability standards less stringent than the P7.1 test that is currently applied for any form of deliverability capacity designation. For CD, CAISO proposes to screen only for cascading P7.1 outages, effectively a far less extreme (but still very rare) condition, that will involve significantly fewer cases where consideration of N-2 outages would prevent a resource from attaining deliverability status. CalWEA anticipates that several GWs of generation capacity could qualify for CD based on this proposed criterion, depending on implementation details.

However, CAISO’s proposal is inconsistent with FERC policy and requires further clarification.

Inconsistency with FERC Policy

The CD proposal is flawed because it has no basis in fact and is discriminatory.  FERC requires non-discriminatory access to the transmission system.  The CD proposal would apply only to a subset of resources that cannot achieve FCD status due to delayed transmission projects that will remedy the assumed N-2 conditions in the generally applicable deliverability test study.  For these resources, CAISO is considering relaxing an assumed system condition in the study and, if the test is passed, effectively grant FCD status to these resources.  While CAISO states that this is a “risk-based approach,” it has not provided any factual basis that supports application of a relaxed assumption only for a subset of resources.  In the Straw Proposal, CAISO cited Wellhead Electric’s comment that discussions in CAISO’s Transmission Development Forum make clear that network upgrade timelines are being delayed up to eight years or more.  This is nearly the entire 10 years that it takes to plan and construct a new transmission line.  CAISO has not explained why using a relaxed deliverability test ensures sufficient system reliability for up to eight years, but not for 10 years or more, for any amount of capacity or duration, let alone the substantial amount of capacity that would qualify for CD for as long as eight years.  Thus, CAISO’s proposed CD policy would be discriminatory towards other resources that could achieve FCD status based on the same relaxed deliverability test. 

As the Joint Framework Proponents noted (p. 3), neither MISO nor PJM uses any N-2 contingency scenario in its deliverability test studies intended to designate RA capacity for resources requesting such designation.  CalWEA and the Joint Framework Proponents have explained that the purpose of the deliverability test is to qualify resources for the CPUC’s and other Local Regulatory Authorities’ Resource Adequacy (RA) programs by ensuring their reasonable availability to serve system load under stressed, but not unreasonably extreme, system conditions. (In discussing dispatch levels, the CAISO “agrees that stressed but not extreme conditions should be assumed in the deliverability test studies.”) The purpose is not to address system reliability directly, which must be, and is, addressed by the RA programs, the CAISO’s TPP, and the reliability studies performed in the generation interconnection process.

Moreover, the CAISO tariff (including sub-tariff policies supporting the tariff) must be just, reasonable, and in the public interest.  CAISO grounds its CD policy not in reliability criteria, but because (at p. 20) “the ISO understands the disruptions resulting from delayed PTO timelines for deliverability upgrades” and “understands that [such] delays … can sometimes result in resource development owners missing deadlines under their power purchase agreements (PPA). This can also result in the PPA counterparty not meeting RA requirements, forcing it to procure a different alternative resource at higher costs.”  CalWEA has advocated broader reforms to the deliverability methodology on the same basis of promoting achievement of the state’s reliability goals and reducing compliance costs, and to further the state’s SB 100 greenhouse gas goals.[1] 

Accordingly, CAISO should modify its N-2 deliverability criterion across the board, rather than only for a subset of resources.

The CD Proposal Requires Clarification

CAISO proposes to apply its CD policy to resources that have been delayed in obtaining deliverability status because transmission projects have been delayed, as verified by CAISO.  On the stakeholder call, in response to a stakeholder question, CAISO stated that this policy would apply to queue cluster 14 (C14), C15, and later queue clusters.  CalWEA requests clarification regarding how CAISO intends to apply the proposed CD policy. 

CalWEA interprets CAISO’s proposal and statements to mean that CAISO would not generally apply the relaxed deliverability test in each interconnection study process. (If it did, it would result in substantially more TPD capacity becoming available from the existing system as well as recently approved TPP transmission upgrades for allocation.)  Instead, CAISO would apply the current, highly restrictive deliverability test, leading to a much smaller amount of TPD capacity available to allocate among projects based on expected transmission construction schedules at that time.  It would then provide CD status only if/when those schedules become delayed during the development period of the transmission upgrade. (To reiterate the point above, this is an arbitrary, non-reliability-based circumstance.)

Additionally, CalWEA requests that CAISO provide implementation details on the following topics:

• Developers will need to be informed as to whether their FCD status is being held up due to an N-2 condition (which would be resolved by CD) and/or an N-1 condition (which would not).  Developers will need to have this information as soon as possible to inform contract negotiations.
• Will CD be a new product (akin to FCD and PCD)?  If it is, it will require a tariff change, which would diminish the purpose of the new policy, which is to bring projects online more quickly.  (A change in the deliverability methodology would not require a tariff change.)

[1] For example, in CalWEA’s January 4, 2023, comments in this initiative, we stated:  “CalWEA is concerned that the CAISO’s deliverability assessment methodology is unnecessarily conservative, … Without a solution to this issue, California’s mid-term reliability and clean energy goals are in jeopardy. Stated another way, these resources will be needed to meet the state’s dual reliability and clean-energy goals. At a minimum, if a substantial number of resources are able to attain deliverability status due to reforms implemented by the CAISO, these resources will help to create a competitive market as LSEs seek to meet their substantial mid-term reliability targets.”

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

The CAISO staff’s presentation of the issues involved in deliverability assessment was excellent.  The summation of stakeholder concerns and the CAISO response were very clear.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

CEERT supports the removal of secondary system needs from interconnection deliverability studies.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

 No comment at this time

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

CEERT supports the CAISO’s goal of reducing the number of local load areas with deliverability constraints. We agree that local capacity and system capacity constraints should be considered more holistically.  We support raising the 5% distribution factor threshold for 500 kV lineoverload constraints to 10%.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

CEERT supports the CAISO proposal to provide “conditional deliverability" to resources waiting for n-2 deliverability upgrades to be completed.  It is important that BPM language defining “conditional deliverability” provides certainty to both buyers and sellers about the amount of capacity that is deliverable so that it can be used for compliance with resource adequacy requirements. CEERT appreciates that it is the CAISO’s intent that conditional deliverability be durable regardless of the interconnection status of other resources.

To the extent feasible CEERT requests that the CAISO provide visibility as to the quantities of conditional deliverability that would be available by resource zones within the CAISO footprint.  Such transparent information should help advance the coordination of procurement using the CAISO’s zonal approach to transmission planning. 

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

No comments at this time.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

CEERT appreciates the CAISO’s understanding that the negative impact that extended delays in completing deliverability upgrades are having on interconnecting clean energy resources that are urgently needed to achieve the state’s decarbonization goals.  Providing “conditional deliverability" that  respects reliability needs is a good interim solution. However, alternatives need to be considered for completing projects when transmission providers repeatedly fall behind schedule for completing deliverability upgrades.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

The California Energy Storage Alliance (CESA) appreciates the opportunity to provide comments on the Generation Deliverability Methodology Review Straw Proposal.  In order to meet the aggressive procurement goals of the CPUC, CAISO must revise its deliverability processes to facilitate contracting between developers and load serving entities.  A key roadblock to contracting is the inability for resources to receive full capacity deliverability status, to meet resource adequacy requirements, prior to all necessary network upgrades being completed whether driven by enforcement of N-2 contingencies or participating transmission owner’s scheduling delays. 

CESA is heartened by the CAISO’s proposal to consider a new deliverability status, “conditional”, in addition to the current full capacity delivery status and interim deliverability status.  While many details regarding conditional deliverability remain to be developed, if conditional deliverability provides a bridge between an earlier commercial operation date and completion of required network upgrades for full capacity deliverability status this could accelerate contracting of new resources.  CESA’s understanding is that bridge deliverability would be provided to projects (1) awaiting network upgrades to address N-2 constraints or (2) whose network upgrades have been delayed by participating transmission owners.   As CAISO develops the additional details regarding conditional delivery status, CAISO should consider how the new policy and proposed rules will facilitate contracting between developers and load serving entities.     

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

Support.  CESA looks forward to additional discussions in the upcoming RA enhancements initiative to align with the CPUC’s slice-of-day construct. 

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

CAISO should continue to evaluate necessary changes to align with the CPUC’s slice-of day-construct in the upcoming RA enhancements initiative. 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

Support

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

Support.

As discussed above, conditional deliverability status could provide benefits if it facilitates contracting between developers and load serving entities.  Providing a bridge between an earlier commercial operation date and completion of network upgrades driven by N-2 constraints for full capacity deliverability status would allow new resources to qualify for resource adequacy earlier which is necessary for contracting.  CESA looks forward to additional details on conditional deliverability and the attributes which materially differentiate conditional deliverability from the exiting interim deliverability status in the next draft of the proposal.  Key questions include:

• Will resources with conditional deliverability be able to provide resource adequacy into the market?
• Will conditional deliverability be awarded to N-2 contingencies that are conditionally credible? 
• When will interconnection customers be notified that conditional deliverability will be received?
• Will conditional deliverability status be irrevocable once awarded?
• Will conditional deliverability apply to any Cluster?

CESA also requests that CAISO perform a high-level study to assist stakeholders in understanding the potential magnitude of additional deliverability made available earlier with the introduction of conditional deliverability.  A starting point could be to compare the amount of deliverability with and without enforcement of N-2 constraints in existing deliverability studies.  While this would overstate the amount of additional deliverability, since awarding additional deliverability would be reduced if the potential for cascading outages remains, the analysis would help convey the potential significance of the new conditional deliverability status.

Lastly, CESA requests CAISO to explain the criteria for determining if the potential for cascading outages would prevent awarding conditional deliverability.  The analysis requested above would be greatly enhanced if the proposed criteria could be enforced and the reduction in deliverability communicated to stakeholders.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

In the event there is consensus among the developer community to fund a larger portion of deliverability upgrades to ensure those network upgrades are built versus reevaluated in a future transmission planning process, CESA would support the option of eliminating ADC-C4 from the guidelines. 

CAISO should provide the average cost of assigned ADNUs.  This data would help stakeholders and the CAISO identify the policy impact to either increasing or removing the constraint guideline.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Support:  Providing a bridge to full capacity deliverability status caused by PTO schedule delays would help facilitate contracting of new resources.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

Intersect Power appreciates the efforts made by the CAISO to refine its deliverability study methodology and appreciates the focus on mitigating the impacts of delays associated with long development timelines for Network Upgrades (NUs). Intersect Power is generally supportive of the CAISO’s Straw Proposal, assuming the additional clarifications and discussion points discussed below are addressed in subsequent iterations of this active process.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

Intersect Power agrees with the CAISO’s proposal to remove the SSN study from the generation interconnection deliverability studies. Intersect Power also agrees with the CAISO’s proposal to continue to perform the SSN study in the annual Transmission Planning Process, as it should be utilized as one of the tools to help proactively identify and mitigate potential renewable energy curtailment issues.   

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

The CAISO should prioritize seeking better alignment between the dispatch levels assumed in the generation deliverability studies and the NQC values provided by the CPUC, especially considering the upcoming paradigm shift to slice-of-day hourly resource values.

It’s difficult for stakeholders, and presumably the CAISO and CPUC, to accurately quantify the reliability attributes of the Resource Adequacy program (both risk abatement and cost effectiveness) when the values for modeling deliverable assets differ from the values for counting those same deliverable assets. The CAISO’s arguments for maintaining the current dispatch assumptions seem focused on providing technical justification for how the assumptions are devised rather than addressing the advantages and/or disadvantages of carrying two different sets of values. The discrepancy between the modeling and counting assumptions will only become starker with the implementation of the slice-of-day framework as the counting levels for each hour will diverge even further from the single-period dispatch assumptions currently utilized by the CAISO.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

Intersect Power supports this proposal.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

Intersect Power supports this proposal; however, more information is required to understand when it would be determined and communicated to the IC that specific upgrades are eligible to qualify the facility for the proposed Conditional Deliverability status (understanding there may be other binding constraints). Further, can the CAISO confirm that no conditions (outside of the control of the IC) would cause an IC to lose Conditional Deliverability status once achieved?

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

Intersect Power supports the CAISO’s efforts to ensure that DNUs needed to provide local deliverability to new projects get built. By increasing the volume of upgrades that qualify as LDNUs rather than ADNUs, the CAISO is increasing the likelihood that those upgrades get built by developers self-funding them as LDNUs, rather than pushing them into the TPP process, where they may or may not be triggered by the IRP resource plans and ultimately approved by the CAISO Board. However, the LDNU/ADNU threshold should be converted to a $/MW threshold, to help ensure that more costly LDNUs do not impose an unreasonable development burden, as explained below. 

The CAISO has proposed raising the ADC-4 dollar threshold. At a minimum, the threshold should be adjusted to reflect construction inflation since the current threshold was adopted, as the CAISO eventually did for the RNU reimbursement cap. For example, the RNU reimbursement limit, originally $60K/MW in 2012, is now close to $80K/MW. 

Thus, it would seem appropriate to at least: (1) update all the dollar limits in the LDNU/ADNU criteria (not just this one) to account for construction inflation since they were adopted; and (2) set up an automatic annual increase based on construction inflation in the future. The index applied to the RNU reimbursement limit could be used for this purpose as well. The desirability of further increases can be better assessed if the CAISO would provide further information about the number and cost of upgrades that would be reclassified from ADNUs to LDNUs, perhaps based on recent historical experience.

Also, developer tolerance for LDNU financing is based, not so much on the number of projects, but more on the MW size.  For example, financing a $30 million upgrade might be hard for a 50 MW project alone, but not for a 500 MW project.  Since the ADNU cost allocations are based on MWs, and it’s the MWs themselves (and not the number of projects) that largely trigger the need for upgrades, perhaps a $/MW threshold would make more sense than arbitrary pre-set limits. 

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Intersect Power supports this proposal, and requests the CAISO address the following:

1. Is the CAISO proposing this will apply to NUs and DNUs or only DNUs?
2. When will IC’s be notified of eligibility for Conditional Deliverability? IC’s will need to have certainty well in advance of a project’s start of construction, so the sooner this information can be determined and disseminated the better.
3. Can the CAISO confirm that no conditions (outside of the control of the IC) would cause an IC to lose Conditional Deliverability status once achieved?

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

LSA is generally encouraged by CAISO’s efforts to improve its deliverability study methodology and appreciates the focus on mitigating delays associated with long development timelines for Delivery Network Upgrades (DNUs). 

To fully assess the proposals, LSA requests that CAISO provide additional data showing the impact that each change might make.  For example, if CAISO has data showing how many upgrades were triggered by N-1 v. N-2 upgrades in the past, that would provide at least a ball-park estimate of the additional deliverability that the Conditional Deliverability proposal might create. 

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

LSA does not oppose removal of the SSN period, but requests that:

1. CAISO provide 2023 summer assessment data with normalized hydro assumptions, to make sure that the high hydro assumptions used in the analysis provided in the staff proposal did not skew the results.  The difficulty of converting data to a chart form would be outweighed by assurance that the assumptions upon which the policy change is based are correct and not anomalous.
2. CAISO continue to monitor the need for economic upgrades during the SSN period.  Deliverability Network Upgrades triggered in the Transmission Planning Process or interconnection studies may be smaller than what would have been triggered by the deliverability study review of the SSN period, so CAISO may need to perform additional analysis in these workstreams to make sure that curtailment issues do not arise.   

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

CAISO should prioritize the discussion on incorporating the CPUC’s slice-of-day hourly resource values into its deliverability study methodology.  CAISO cannot formally adopt these hourly values until CPUC finalizes the NQCs that it will use for the 2025 implementation year.  However, there are aspects of the shift to hourly values that CAISO should consider now, including:

1. Will CAISO consider incorporating different values for each hour included in the deliverability study? 
2. Does the additional accuracy of hourly values outweigh the additional administrative burden?
3. How would a shift to hourly values impact the volume of deliverability available on the existing grid?

LSA encourages CAISO to prioritize these topics as part of the upcoming RA initiative. 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

LSA supports this proposal.  However, as noted above, the CAISO should provide information about the potential impact. 

In addition, the CAISO should reconcile its statements at the stakeholder meeting about 5% vs. 10% DFAX values for specific projects with the continuing “DFAX circle” terminology in the methodology description.  For example, what is the impact to a project has less than a 10% DFAX itself but is near others above that threshold value?

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

LSA supports CAISO’s efforts to reduce delays associated with upgrades required for N-2 contingencies but would like CAISO to provide more details about this proposal in the next iteration, including:

1. Will Conditional Deliverability be a new product that requires FERC approval?
2. Does Conditional Deliverability mean there is more Transmission Plan Deliverability available or just that the allocation occurs earlier?
3. How will CAISO define a cascading outage?  How common is this and how will it be applied?

In addition, LSA requests clarification below about two aspects of this proposal: (1) overlap with Interim Deliverability; and (2) timing of notification of Interim and/or Conditional Deliverability.

Overlap With Interim Deliverability: 

CAISO should provide clarification regarding the overlap between Interim and Conditional Deliverability.  The written proposal, and discussion at the stakeholder meeting, implied that Conditional Deliverability would cover the period between COD and completion of upgrades for N-2 violations.  However, it is not clear how this concept would apply in perhaps-common situations where projects require other DNUs (e.g. to mitigate N-1 violations) that might not be completed until after COD.

For example, assume a project requires two types of upgrades: (1) an N-2 upgrade that will be complete 6 years after the planned COD (“Year 6”); and (2) one or more N-1 upgrades that will be complete 3 years after COD (“Year 3”).  Currently, the project would not get Full Capacity Deliverability Status until Year 6 and would need Interim Deliverability for years 1-6.  Thus, this project would have a strong incentive to delay its COD until Year 6 to avoid the Interim Deliverability risk, and potential RA deficiency penalties under its PPA.

Under CAISO’s proposal, it appears that the project could get Conditional Deliverability for Years 4-6 but would still need Interim Deliverability for Years 1-3 (i.e., when the N-1 upgrades are still incomplete).  Thus, this project would still have a strong incentive to delay its COD, at least until Year 4, to avoid the Interim Deliverability risk. 

In other words, Conditional Deliverability would only provide relief if a project: (1) requires no other upgrades that will be completed after COD; or (2) can also get an assurance that it will get Interim Deliverability while waiting for other upgrades besides those for N-2 contingencies.  CAISO should clarify these types of interactions in the next iteration of the proposal and address the need for earlier assurances of Interim Deliverability (see below) as part of its proposal.

Timing of Notification of Interim and/or Conditional Deliverability:

CAISO must inform developers if they will get Interim and/or Conditional Deliverability as soon as possible, preferably when their projects receive Transmission Plan Deliverability awards.  As the example above demonstrates, projects may require both Interim and Conditional Deliverability to maintain Resource Adequacy value while upgrades (and their projects) are built.  If developers do not know if they will get Interim and/or Conditional Deliverability when they negotiate contracts, they will have to consider delaying CODs until they have more certainty, which defeats the purpose of CAISO’s efforts to reduce delays associated with transmission upgrades, in particular those related to N-2 contingencies.  The best way to avoid delays would be for CAISO to inform developers about the availability of Interim and/or Conditional Deliverability concurrently with the release of TPD allocation results. 

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

LSA supports CAISO’s efforts to ensure that DNUs needed to provide local deliverability to new projects actually get built.  By increasing the volume of upgrades that qualify as LDNUs rather than ADNUs, CAISO is increasing the likelihood that those upgrades get built by developers self-funding them as LDNUs, rather than pushing them into the TPP process, where they may or may not be trigger by the IRP resource plans and ultimately approved by the CAISO board.  However, the LDNU/ADNU threshold should be converted to a $/MW threshold, to help ensure that more costly LDNUs do not impose unreasonable development burden, as explained below. 

The CAISO has proposed raising the ADC-4 dollar threshold.  At a minimum, the threshold should be adjusted to reflect construction inflation since the current threshold was adopted, as the CAISO eventually did for the RNU reimbursement cap.  LSA members have noticed that more projects have been classified as ADNUs and not LDNUs in recent years, and at least part of this change may be due to the combination of the current pre-set threshold and rising costs in recent years.  For example, the RNU reimbursement limit, originally $60K/MW in 2012, is now close to $80K/MW. 

Thus, it would seem appropriate to at least do this: (1) update all the dollar limits in the LDNU/ADNU criteria (not just this one) to account for construction inflation since they were adopted; and (2) set up an automatic annual increase based on construction inflation in the future.  Perhaps the index applied to the RNU reimbursement limit could be used for this purpose as well.  The desirability of further increases can be better assessed if the CAISO would provide further information about the number and cost of upgrades that would be reclassified from ADNUs to LDNUs, perhaps based on recent historical experience.

Also, developer tolerance for LDNU financing is based, not so much on the number of projects, but more on the MW size.  For example, financing a $30 million upgrade might be hard for a 50 MW project alone, but not for a 500 MW project.  Since the ADNU cost allocations are based on MWs, and it’s the MWs themselves (and not the number of projects) that largely trigger the need for upgrades, perhaps a $/MW threshold would make more sense than arbitrary pre-set limits.  LSA is willing to discuss reasonable thresholds of this type as the initiative progresses.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

See comments to question 5 above regarding the need for more details and the importance of notifying developers as soon as possible.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

Comments from Middle River Power LLC (“MRP”).

While MRP accepts the CAISO’s representation regarding the Secondary System Need (“SSN”) analysis, MRP believes the current conversation about modifying the CAISO’s deliverability analysis is inadequate given the imminent move to a Slice of Day (“SoD”) Resource Adequacy (“RA”) framework.

MRP supports the CAISO’s proposals to (1) maintain the current methodology for dispatch levels; (2) use a 10% DFAX for lines 500 kV and above (though MRP seeks confirmation that would also apply to all associated equipment); (3) the continued study of N-2 contingencies and the creation of “conditional deliverability” for facilities that rely on upgrades not yet constructed to mitigate the N-2 overloads and (4) the proposal to use conditional deliverability in situations in which needed network upgrades are delayed.  

With regards to the CAISO’s proposal to revise the ADNU/LDNU Guidelines, MRP supports either the highest cost figure proposed by the CAISO or the elimination of the Area Constraint Guideline ADC-C4.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

With regards to the CAISO’s proposal to eliminate the SSN assessment, MRP accepts the CAISO’s representation that, with the update to study storage at 50%, the SSN is rarely more binding than High System Need (”HSN”) scenario.[1]  Eliminating the SSN scenario, however, seems philosophically inconsistent with the California Public Utility Commission’s (“Commission’s”) move towards a SoD RA framework, which, by the Commission’s own words, “…assesses the needs of the grid for every hour of the day.”[2]  If, in fact, an RA program must be capable of addressing the needs of the grid for every hour of the day, the CAISO should immediately engage all stakeholders in a conversation about expanding the number of snapshot deliverability analyses, not reducing that number.  Conversely, the CAISO should be working to demonstrate that a single HSN analysis can reliably ensure that resources are deliverable to the aggregate of demand for every hour of the day. 

Simply put, the current narrow conversation regarding modifications to the CAISO’s deliverability analyses seems completely inadequate given the imminent move to a SoD framework.  The CAISO acknowledges this in the straw proposal, but only in a tangential way.[3]  While MRP appreciates this initial deliverability conversation and supports many aspects of the CAISO’s proposal – some of which involve keeping things the way they are – MRP respectfully urges the CAISO to quickly expand the conversation about deliverability to better fit the approaching SoD paradigm. 

[1] CAISO August 22, 2023 Deliverability Assessment Methodology Revisions Straw Proposal (“Straw Proposal”) at page 10.

[2] D.22-06-050 at page 76 (emphasis added). 

[3] On page 10 of the Straw Proposal, the CAISO observes that it will explore other study conditions and study scenarios proactively.  This works seems fundamental to the larger necessary conversation about deliverability under a SoD framework. 

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

MRP supports this aspect of the Straw Proposal.   

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

MRP supports this aspect of the CAISO’s proposal.  As MRP understands, any reference to use a 10% DFAX for all transmission lines 500 kV and above would include all equipment associated with those lines; if MRP’s understanding is incorrect, MRP asks the CAISO to expressly note that error.  Further, MRP appreciates the CAISO’s commitment to have its transmission planning engineers engaged in the parallel conversation about “local deliverability” in the IPE 2023 Phase 2 initiative.[1]

[1] Straw Proposal at page 15.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

MRP supports this aspect of the Straw Proposal.  MRP appreciates the CAISO’s proposal to provide conditional deliverability until the time that network upgrades needed to mitigate overloads caused by N-2 contingencies are constructed.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

MRP supports the CAISO’s proposals either to raise the cost threshold to $35 M in current dollars or to eliminate Area Constraint guideline ADC-C4.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Consistent with MRP’s response in item 5 above, MRP supports this aspect of the proposal to provide conditional delivery until the time the deliverability upgrades are completed. 

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

New Leaf Energy, Inc. (“NLE”), an independent developer of solar generation and energy storage, thanks the CAISO for the significant progress so far in this stakeholder initiative, as reflected in the Deliverability Assessment Methodology Straw Proposal and the August 29, 2023 stakeholder call.

During the stakeholder call, CAISO staff stated that the stakeholder proposal to consider creating separate Local and System deliverability designations would not be taken up in this initiative but rather in a new Resource Adequacy (“RA”) stakeholder initiative that will commence in mid-October. NLE appreciates this additional detail about the procedural path forward and does not object to a two-month delay, particularly considering the volume of time-sensitive work that the CAISO is currently leading in this and concurrent stakeholder initiatives.

However, NLE believes that further postponements to the examination of this important issue could negatively impact market participants who are developing RA resources.  The proposal to bifurcate the System and Local deliverability studies so that the reliability contributions of Local RA resources could be assessed differently than those of System RA has been advanced by diverse stakeholders since before this initiative even opened[1] and has yet to be given due consideration. This issue is of critical importance, as the status quo may be creating an unnecessary bottleneck to the reliable deployment of new Local RA resources. It is well worth the CAISO’s and stakeholders’ attention.

Additionally, NLE is uncertain whether the discussion of TPD allocation process reforms belongs in this initiative or the CAISO’s Interconnection Process Enhancements (“IPE”) initiative, and we therefore request clarification from the CAISO about the appropriate venue to continue these discussions. In both this initiative[2] and in the IPE initiative,[3] NLE has proposed that resources within a given transmission planning deliverability (“TPD”) allocation group receive additional points for:

1. Projects Sited within Local Capacity Areas (“LCAs”): In the August 16, 2023 IPE comments, NLE was pleased to receive support from CPUC Energy Division Staff,[4] San Diego Gas & Electric (“SDG&E”),[5] the California Community Choice Association (“CalCCA”),[6] the Northern California Power Agency (“NCPA”),[7] and GridStor[8] for its proposal to include an opportunity to allot points to resources sited in LCAs in the scoring rubric used to enter the study process. NLE believes that such resources merit prioritization within TPD allocation groups as well. In the event that reforms to the TPD allocation process are considered in this initiative, NLE reiterates the need for small but meaningful reforms that would boost the commercial viability of new Local RA resources and improve local reliability.
2. Projects with Lower Impacts on Overloaded Transmission Elements: As NLE has argued in its earlier comments,[9] awarding deliverability to projects with lower distribution factors (“DFAX”) would allow more megawatts of deliverability to be awarded, making more efficient use of existing and approved transmission to provide reliability to loads.

[1] See, e.g., Comments of the California Energy Storage Alliance (“CESA”) on the 2023 Draft Policy Initiatives Catalog (September 23, 2022), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/822f5bcd-8a6a-4dd4-8fc0-033d8c482dac#org-2cd406f2-24d6-463a-9f72-1f3f6923dc85; Comments of the California Wind Energy Association (“CalWEA”) on the 2023 Draft Policy Initiatives Catalog (September 23, 2022), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/822f5bcd-8a6a-4dd4-8fc0-033d8c482dac#org-01ab11c9-9743-4541-a7a6-52fcd64fa825; and Comments of Terra-Gen on the 2023 Draft Policy Initiatives Catalog (September 23, 2022), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/822f5bcd-8a6a-4dd4-8fc0-033d8c482dac#org-f5a41153-616b-4a5e-9460-e886951aa5db. See also Comments of the Bay Area Municipal Transmission Group (“BAMx”) on the Generation Deliverability Methodology Review Update Paper (January 4, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/4c7edbc6-5c17-4c7d-8e9a-fe31a4a557ad#org-65866bc3-75f7-4bdf-85de-9f121f709c57; Comments of CESA on the Generation Deliverability Methodology Review Update Paper (January 4, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/4c7edbc6-5c17-4c7d-8e9a-fe31a4a557ad#org-1c4586fc-f6fa-435b-ae66-4b153ed24b35; Comments of CalWEA on the Generation Deliverability Methodology Review Update Paper (January 4, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/4c7edbc6-5c17-4c7d-8e9a-fe31a4a557ad#org-0a308017-827f-48dc-9680-291f35dcd574; Comments of the Large-Scale Solar Association (“LSA”) on the Generation Deliverability Methodology Review Update Paper (January 4, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/4c7edbc6-5c17-4c7d-8e9a-fe31a4a557ad#org-fb4bbe73-60c5-4370-ada7-d3830b30b191; and Comments of NLE on the Generation Deliverability Methodology Review Update Paper (January 4, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/4c7edbc6-5c17-4c7d-8e9a-fe31a4a557ad#org-51f8fe8d-ea67-483c-a035-2a1272b6b0e3. 

[2] Comments of NLE on Issue Paper (June 22, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/752668bc-f8b9-4a78-9889-4d22246c5697#org-7f4b485a-cb66-411a-910e-2f7b98d3fda8.

[3] Comments of NLE on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-8c46c9ca-5e4d-4839-8e50-4be5aedc3c4a.

[4] Comments of the CPUC on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-d10012c7-5c68-4e2e-80c8-c32af3f92d7c (“CPUC staff urge CAISO to consider additional broad concepts, including: . . . Efforts to prioritize projects needed to meet Local Reliability and reduce the cost of compliance with Local Resource Adequacy requirements. CPUC staff support the CAISO taking strong consideration of proposals that better enable new resources that would support or improve local reliability to interconnect in local constrained transmission areas.”).

[5] Comments of SDG&E on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-42e77676-aa33-4068-825b-c23b2aeb3617 (“Interconnection request intake[:] . . . SDG&E strongly supports New Leaf Energy’s proposal to prioritize local RA which enhances reliability where load growth occurs.”).

[6] Comments of CalCCA on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-d8462b15-4465-49d6-a464-9df1f71ab2ce (“Additionally, CalCCA generally supports New Leaf Energy’s proposal to prioritize projects in local areas, as it will assist in CCAs developing projects in their own communities and near load centers.”)

[7] Comments of NCPA on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-27e3db69-fd35-4cf0-a1b2-f8f75781f49d (“These types of projects should not be discouraged from entering the queue. Examples include: . . . Projects located in local capacity zones. Projects located in local capacity zones (especially zones that are short of capacity) are potentially valuable additions to the grid in terms of reliability and mitigation of market power.”).

[8] Comments of GridStor on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-07fd224d-48db-4064-a134-9005084d55a8 (“For interconnection request intake: . . . GridStor supports New Leaf Energy’s proposal to give priority scores to resources that are sited in LCAs, where local resources are needed now or will be needed in the future to avoid local resource adequacy deficiencies.”).

[9] Comments of NLE on Issue Paper (June 22, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/752668bc-f8b9-4a78-9889-4d22246c5697#org-7f4b485a-cb66-411a-910e-2f7b98d3fda8; Comments of NLE on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-8c46c9ca-5e4d-4839-8e50-4be5aedc3c4a.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

NLE appreciates the level of detail the CAISO put into researching the likelihood of system shortages during the SSN window utilizing the most recent peak load data. NLE supports the CAISO's decision to remove SSN studies in GIP and TPD allocation. NLE believes that the load data supports this decision. This proposal would remove unnecessary burdens in the allocation of TPD while continuing to maintain deliverability through the HSN studies.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

NLE recommends that CAISO consider updating its offshore wind dispatch assumptions to align with the most recent estimates produced by the National Renewable Energy Lab (“NREL”),[1] as they are likely to be more accurate than current assumptions.

[1] See CAISO 20 Year Transmission Outlook and Approach to Offshore Wind (August 16, 2023), p. 27, available at: http://www.caiso.com/InitiativeDocuments/Presentation-20-Year-Transmission-Outlook-Aug-16-2023.pdf  (“The data analysis indicates that the average offshore wind generation is 83% of installed capacity for HSN hours and 45% for SSN hours.”).

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

NLE supports the DFAX threshold increase for 500 kV line overload constraints and agrees with the CAISO that this is a more practical threshold.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

NLE strongly supports the CAISO’s proposal to create a Conditional Deliverability designation, including for projects that are waiting for n-2 deliverability upgrades to be completed.

The Straw Proposal acknowledges that duration is one key distinction between the existing Interim Deliverability status and the proposed Conditional Deliverability status. Importantly, Conditional Deliverability would not be at risk of being lost each year; it would be available to a generator until the N-2 contingency mitigation is completed, at which point the generator would receive its allocated deliverability status (e.g., Full Capacity Deliverability Status (“FCDS”)). This durability will make it possible for new resources to sign power purchase agreements (“PPAs”) and maintain their earliest possible Commercial Operation Dates (“CODs”) before the N-2 mitigations are completed.

There are four areas where NLE seeks additional clarity from the CAISO:

1. Risk-Based Considerations: NLE understands the CAISO’s rationale for continuing to include both N-1 and N-2 contingencies in its deliverability studies. We commend the CAISO for its decision to adopt the additional step of incorporating a risk-based approach to evaluate resources for Conditional Deliverability. Awarding Conditional Deliverability to projects with minimal or low-probability reliability concerns would allow more reliable resources to move forward with their current development timelines. NLE suggests a modification to this risk-based approach that would ensure that all low-risk resources that are delayed by long-lead time network upgrades be considered for Conditional Deliverability. As not all outages are equal, CAISO could identify specific low-risk or low-probability outage types that appear in both N-1 and N-2 contingencies and consider allocating Conditional Deliverability to the subset of resources that only triggered overloads because of these outage types. For example, transformer and breaker failures are generally considered to be low-probability events, and projects whose overloads appear in N-1 and N-2 contingencies were driven by this type of failure would be good candidates for Conditional Deliverability. By using this approach, the CAISO could expand Conditional Deliverability based on an established risk-based threshold.
2. Timing of Conditional Deliverability: NLE agrees with the many stakeholders on the August 29, 2023 call that requested additional clarity about when a generator would be notified of its receipt of Conditional Deliverability. NLE suggests that the CAISO should award Conditional Deliverability during the TPD allocation process. This would ensure that a project is effectively pre-approved for Conditional Deliverability when its other mitigations are completed, ensuring that project developers have advanced visibility so that they can structure their offtaker contracts and plan procurement and construction activities accordingly to meet COD.
3. Applicability of Conditional Deliverability: NLE requests that the CAISO clarify if it can implement this proposal before the upcoming early-2024 TPD allocation process. NLE supports early implementation of this proposal to benefit projects in the next TPD allocation cycle. NLE also requests clarity as to whether Conditional Deliverability will apply only to projects that participate in future TPD allocations, or also to existing projects with TPD awards that have not yet received FCDS. The latter would better promote the CAISO’s goal of supporting rapid deployment of new resources.
4. Conditional Deliverability Transparency: NLE seeks clarification from the CAISO regarding how Conditional Deliverability will be communicated. In the current TPD allocation process, projects are unaware of which policy-driven upgrades need to reach completion before achieving FCDS. NLE hopes to avoid similar challenges caused by a lack of transparency in the Conditional Deliverability award process. NLE recommends that during the TPD allocation process, the CAISO provide a list to Interconnection Customers specifying which projects are eligible to secure Conditional Deliverability and which are not. Furthermore, this transparency would help developers understand which DNUs are on a critical path because they are still awaiting approval in the Transmission Planning Process (“TPP”) and those that have already been approved. The CAISO provides transparency regarding Precursor Network Upgrades (“PNU”) during Phase 1 and Phase 2 studies, and NLE encourages the same level of transparency regarding DNUs for Conditional Deliverability.

The CAISO’s proposal aims for a pragmatic balance between ensuring that resources are deliverable when needed and supporting the scale and speed of resource development that California needs to meet its clean energy goals. NLE applauds the CAISO’s willingness to not let the perfect be the enemy of the good but anticipates that this proposal may have a limited real-world impact. Many Area Deliverability Network Upgrades (“ADNUs”) are not exclusive to a single worst outage and limiting element pair, but rather have multiple outage combinations that overload the limiting element(s). In other words, eliminating the N-2 contingency may, in many instances, fail to create conditions that would make generators eligible for Conditional Deliverability because there may be an N-1 ADNU with nearly the same overload percentage remaining. NLE encourages the CAISO to consider the comments above regarding a more holistic risk-based approach that may expand the potential for granting Conditional Deliverability. There may be conditions where it would enhance reliability to grant Conditional Deliverability and enable resources to come online sooner.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

The CAISO seeks feedback on the ADC-C4 Area Constraint guideline, which dictates that if a constraint impacts ten or more new and existing generators and the mitigation costs more than $20 million, that constraint would be classified as an Area Constraint. The guideline has reduced the number of Local Deliverability Network Upgrades (“LDNUs”) and increased the number of ADNUs. As PG&E points out, this has limited the pathways for Interconnection Customers to fund upgrades.[1] It has also contributed to the CAISO’s enormous queue by reducing the incentive for projects to drop out of the queue when facing high LDNU costs; instead, these projects can simply remain in the queue in the hope that the CAISO approves their ADNU mitigations in a future TPP cycle.

NLE agrees with the CAISO and PG&E that raising the threshold to an amount higher than $20 million would be beneficial. However, NLE believes that both of the proposed cost threshold increases offered by the CAISO (i.e., $25 million for Option 1 and $35 million for Option 2) may still be too modest and therefore not achieve the desired effect. A threshold as high as $50 million—perhaps indexed to construction inflation—may be more effective. In any case, the CAISO should provide more information on the impacts of the various thresholds under consideration (e.g., how many and what types of upgrades would it reclassify).

Finally, NLE suggests that the CAISO may want to reconsider not just the cost threshold but the threshold for the number of queued generators to require an ADNU. Given the queue growth since the CAISO adopted the ADC-C4 guideline in 2020, ten queued and existing generators simply is not the indicator that it once was to determine whether an issue is local versus area. Also, including existing generators in the count does not provide a strong indication of what new transmission investments would be beneficial to new generators seeking to interconnect in that area of the grid. Therefore, the CAISO should only consider counting new generators within this criterion.

[1] CAISO Deliverability Assessment Methodology Revisions Straw Proposal (August 22, 2023), p. 19.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

NLE enthusiastically supports the CAISO’s proposal to create a Conditional Deliverability designation for projects experiencing delayed participating transmission owner (“PTO”) timelines for deliverability upgrades. As stated in its response to Question 5, NLE appreciates the CAISO balancing the need to ensure that RA resources are deliverable when necessary with the need to expeditiously bring new RA resources online.

There are two areas where NLE seeks additional clarity from the CAISO:

1. Timing of Conditional Deliverability: The Straw Proposal states that when a PTO timeline delay occurs, the CAISO would provide Conditional Deliverability based on the original upgrade schedule.[1] Similar to Precursor Network Upgrades, which the CAISO communicates during Phase 1 and Phase 2 studies, approved ADNUs are defined upgrades with projected schedules. The CAISO should communicate these schedules to projects during the TPD allocation process, and this should provide the basis for the start of a project’s Conditional Deliverability eligibility. This information is critical because it provides schedule certainty to reference during the financing stage of a project. As discussed in response to Question 5, the timing is critical to making Conditional Deliverability status valuable by actually helping projects come online sooner.
2. Definition of Exception Conditions: The CAISO stated that it will be “taking a risk-based approach and respecting reliability needs” in deciding which projects experiencing PTO delays will receive Conditional Deliverability.[2] NLE requests more specificity on what this approach entails and what conditions would be eligible.

Finally, NLE reiterates its appreciation for the reasonableness and practicality embodied in this proposal, yet remains troubled by the volume and duration of PTO network upgrade delays. In addition to creating the Conditional Deliverability designation, NLE encourages the CAISO to continue working with the PTOs and stakeholders to explore ways to address this underlying problem. There must be greater accountability for the PTOs to provide more accurate timelines upfront and to then remain on schedule—especially for elements within the PTOs’ control (e.g., the time lag between the CAISO approving an upgrade and the PTOs submitting required permit applications; the time lag between the CAISO’s approval and the PTOs procuring equipment; and similar administrative functions).

At minimum, this reality underscores the arguments put forward by many stakeholders in the IPE initiative that it is unreasonable to entertain a firm time-in-queue limit for generators without accounting for the role that the PTOs play in impacting that timeframe.[3]

NLE thanks the CAISO for its ongoing leadership in this stakeholder initiative and for its consideration of these comments.

[1] CAISO Deliverability Assessment Methodology Revisions Straw Proposal (August 22, 2023), p. 20.

[2] CAISO Deliverability Assessment Methodology Revisions Straw Proposal Stakeholder Call Slides (August 29, 2023), p. 9.

[3] See, e.g., Comments of GridStor on Track 2 Working Groups (August 15, 2023), available at: https://stakeholdercenter.caiso.com/Comments/AllComments/1198f707-8b68-4560-bb9a-7dd64ea2b57d#org-07fd224d-48db-4064-a134-9005084d55a8.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

NextEra Energy Resources, LLC (NextEra Resources) supports the California Independent System Operator’s (CAISO) review of its Generation Deliverability Methodology. NextEra sees deliverability as a critical component to California meeting its mid-term reliability and clean energy goals. NextEra Resources is supportive of CAISO’s latest proposal and believes it strikes the right balance between reliability and project development opportunities. Most specifically, NextEra Resources appreciates the CAISO’s recognition of the decreasing risk of resource shortages during the Secondary System Need (SSN) study period and the proposal to remove the SSN study from generation interconnection deliverability studies.  Additionally, NextEra Resources is strongly supportive of CAISO’s proposal to consider a new “conditional” deliverability status.  While more details on conditional deliverability are needed, the proposal narrows a critical gap that exists in the interconnection process between resources that have commercial operations dates that precede the completion of network upgrades driven by N-2 constraints.  This has created unnecessarily long delays before a resource is able to receive Full Capacity Deliverability Status (FCDS) and allowing a resource to receive conditional deliverability while waiting for those upgrades to be completed has the potential to vastly improve the disruptions that these delays create to a project’s timeline. 

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

In previous comments, NextEra Resources recommended updating the dispatch assumptions used for storage during the Secondary System Need (SSN) time window to better align with how storage is dispatched in real time. NextEra Resources supports CAISO’s proposed removal of the SSN study from the generation interconnection deliverability studies and agrees with CAISO’s analysis that with adequate resource supply the risk of resource shortage in the SSN study period is less of a concern.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

While NextEra Resources appreciates the CAISO’s recognition of the need to reevaluate deliverability assumptions related to any changes to regulatory authorities’ resource valuation assumptions, there was no reference to the offshore wind generation estimates that were provided to CAISO by the National Renewable Energy Laboratory (NREL) based on wind model information for year 2007-2013 in the Straw Proposal.  However, CAISO indicated in the 20-Year Transmission and Approach to Offshore Wind stakeholder presentation that NREL’s data analysis indicated that the average offshore wind generation is 83% of installed capacity for Highest System Need (HSN) hours and that the offshore wind dispatch at HSN hours “will be modified if needed.”[1]  NextEra Resources would appreciate additional clarification of when this assessment will be completed, how any potential changes will be socialized, and if the changes will be incorporated into the Deliverability HSN cases as well. 

[1] California Independent System Operator, “20 Year Transmission Outlook and Approach to Offshore Wind” Presentation, August 16, 2023.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

NextEra Resources is supportive of CAISO raising the 5% DFAX threshold to 10% on 500 kV line overload constraints.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

NextEra Resources has no additional comments at this time.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

NextEra Resources has no additional comments at this time.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

As previously noted, NextEra Resources is supportive of conditional deliverability to be awarded if the Area Delivery Network Upgrade (ADNU) is driven by an N-2 contingency with an approved upgrade, or, if the ADNU is approved and the in-service date is delayed due to network upgrade delays. However, additional questions remain regarding how this new deliverability status will be implemented. Specifically, how does CAISO plan to allocate conditional deliverability?  Does CAISO plan to establish any rules or limitations for the resource to maintain deliverability while the upgrade or new transmission is implemented?  At a minimum, CAISO should provide additional transparency regarding the ADNUs that a project is dependent upon when deliverability is allocated.  At present, the CAISO does not provide any visibility into a list of upgrades that a project is dependent upon prior to receiving FCDS status. 

Moreover, while NextEra Resources is supportive of the CAISO’s proposed risk-based approach, it is not clear what criteria the CAISO will be using to assess that risk.  While NextEra Resources understands that cascading outages will be assessed (which present a very low probability but a high risk), it’s unclear whether any other criteria will be included in the CAISO’s assessment that presents a higher probability of occurrence.  NextEra encourages the CAISO to provide a more detailed description of criteria that may be included in the next iteration of the proposal.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

Ormat supports CAISO’s proposed changes to the deliverability assessment methodology, particularly related to s conditional deliverability status and other changes that make deliverability for new resources easier to achieve and less dependent on contingencies. We encourage CAISO to prioritize geothermal resources because they maintain reliability. 

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

Ormat supports CAISO’s proposal to remove the SSN from generation deliverability studies.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

Ormat has no objection to CAISO’s intent to retain the current methodology for determining dispatch levels, however limiting VERs to their NQC should be taken into consideration so long as it will not result in curtailment of others to levels below their NQCs. 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

Ormat supports the proposal to increase the DFX threshold for 500 kV lines to 10%.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

Ormat supports CAISO’s proposal to implement conditional deliverability for resources otherwise limited by n-2 contingencies, appears to be a reasonable approach.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

Ormat has no comment.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Ormat supports implementing conditional deliverability to mitigate a delay in transmission projects. CAISO should expand conditional deliverability to interconnection for baseload geothermal resources.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

Pacific Gas & Electric (PG&E) appreciates the opportunity to comment on the Generation Deliverability Methodology straw proposal.  In general, PG&E supports all six of CAISO’s straw proposal responses to stakeholder concerns. PG&E recommends CAISO particularly focus on Item five to re-evaluate the Area Delivery Network Upgrades (ADNU)/ Local Delivery Network Upgrades (LDNU) Guidelines and work towards resolving increasing congestion on the grid.  PG&E recommends amending the Area deliverability Constraints (ADC) criteria that would support a definitive pathway for generators to achieve Transmission Plan Deliverability (TPD). The current ADC criteria increases the number of ADNUs, limiting the TPD allocation and resulting in the withdrawal of generation required for local capacity requirements and Load Serving Entities (LSE) procurement targets.

The current ADCs criteria results in more ADCs being identified, which causes TPD not being released, and interconnection customers (ICs) that do not receive TPD then withdraw in instances where local capacity is in shortage.  This results in LSEs (including PG&E) having a smaller pool of projects to choose from when seeking power purchase agreements. 

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

PG&E recommends CAISO re-evaluate the Area Deliverability Constraints (ADC) criteria in effect (Business Practice Manual (BPM) GIDAP 6.1.1.4) since the amount of ADNUs identified have restricted generators from deliverability allocation and resource developers have not been given proper pathways to fund and contribute to the accumulating ADNUs. Overall, PG&E desires that a reasonable number of ADCs can be converted into Local Deliverability Constraints (LDC) and more pathways for ICs to fund ADNUs coming out of this ADC criteria re-evaluation.

Renewable base portfolio alignment: PG&E noticed that the California Public Utilities Commission (CPUC) renewable base portfolio mapped within the five percent electric circle is usually underestimated, making it very easy for the number of total megawatts (MW) inside the electric circle to exceed the base portfolio value. This results in an auto-satisfaction of criteria in ADC-C2 (bulletin 2), ADC-C3 (bulletin 1) and ADC-C4 (bulletin 2) and eventually makes a constraint easily qualify for an ADC.

PG&E suggests the CAISO work with the CPUC to review and align the renewable base portfolio. If the total MW amount of new generation is always expected to exceed the CPUC renewable base portfolio, there is no justifiable reason for having this as a criterion in BPM GIDAP 6.1.1.4.

ADC criteria re-evaluation: PG&E recommends the amendment of ADC-C4 criteria, specifically the cost threshold. CAISO should evaluate a higher cost threshold accounting for inflation and recent unit costs, with annual updates to account for escalating costs. This will reduce the number of ADCs by converting a reasonable number of ADCs into LDCs. Developers can then fund and build LDNUs, which they have more control over to acquire TPD allocation.

Provide more pathways for developers to fund ADNU and Real-time congestion-driven upgrades: Once all ADCs are identified, the generators choosing Option(A) behind an ADNU are not required to build the network upgrade so there is no pathway for the ICs who are willing to fund the upgrade and acquire the Deliverability. The following reforms are recommended by PG&E to address this concern:

• • Accumulating ADNU not being built: To support a TPD pathway for generators besides converting ADNUs into TPP Policy projects, PG&E suggests CAISO explore creating alternative pathways for ADNUs to be funded by ICs (e.g., on a pro-rata cost share), provided that an ADNU-driven policy project only targets to increase Deliverability so a PTO would not prioritize such network upgrade over a reliability network upgrade (RNU).  A new alternative would lead to earlier construction of ADNUs and faster TPD allocation for ICs who are willing to fund that ADNU. This could be associated with Option B reform.
  • Increasing congestion: This scenario is caused by more energy-only projects online, Partial Capacity Deliverability Status (PCDS) projects online, and Full Capacity Deliverability Status (FCDS) projects online without building ADNU in the existing power grid. PG&E recommends CAISO explore creating alternative pathways for congestion driven network upgrades to be identified sooner and funded by ICs besides proposing TPP Economic projects. This would allow such competitive network upgrades to be funded by ICs behind the congestion and reduce long-term congestion costs. This would be associated in parallel with TPP Economic project reform.
  • ADNU involving affected system: Historical deliverability cluster studies in the PG&E system have identified deliverability upgrades due to the limitation on non-CAISO controlled third party facilities that could limit a great range of generators from achieving their maximum MW capacity.  Such constraints can become a bottleneck to achieving TPD allocation and FCDS status in certain pockets. PG&E requests that CAISO create timelines for faster coordination with affected systems, methods to implement mitigation solutions that support the in-service date (ISD) for a generator seeking FCDS in PG&E system. Regarding mitigation solutions, PG&E cautions against considering remedial action schemes (RAS) as the most optimal solution, especially when the RAS design involves hybrid resources, interaction with neighboring utilities, or is adding to existing RAS logic.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

REV Renewables (REV) supports the direction of CAISO’s Generation Deliverability Straw Proposal and appreciates CAISO analyzing stakeholder feedback to arrive at these solutions.

REV urges CAISO to ensure the changes from this initiative are applied to the 2024 Transmission Plan Deliverability (TPD) allocation cycle. Given the large volume of interconnection requests in Cluster 14, CAISO should not delay implementation. The changes in this proposal could provide scarce deliverability to more projects and therefore improve project viability for Cluster 14 and beyond.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

REV supports CAISO’s proposal to remove the secondary system need (SSN) from generation interconnection deliverability studies. REV appreciates CAISO’s analysis that there is a decreasing risk in recent years of resource shortages during SSN, and that SSN is rarely more binding than the high system need (HSN) period. REV agrees that CAISO should continue to study SSN to ensure there is not a change to this trend, but this study should not limit deliverability during that observational period.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

REV has no comment on the dispatch level proposal at this time.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

REV supports the proposal to increase from 5% to 10% DFAX threshold for 500kV line overload constraints as a more practical threshold for identifying significant impacts.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

REV supports CAISO’s proposed treatment of n-2 studies and allowing conditional deliverability to projects awaiting n-2 network upgrades but are not at risk of cascading outages, assuming no other constraints are binding.

REV requests that CAISO provide clarity that conditional deliverability is assured during the entire time the project is awaiting the upgrade(s) to resolve the n-2 contingency to receive full capacity deliverability status (FCDS). This conditional deliverability status should make a project commercially viable in the interim and provide Interconnection customers the ability to enter into resource adequacy contracts. REV also supports CAISO that, “Unlike interim deliverability, conditional deliverability would not be lost just because earlier queued projects come on-line, assuming that no other constraints are binding.”

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

REV supports Option 3 to eliminate the Area Constraint guideline ADC-C4. The current ADC-C4 criteria of 10 generating units and a cost threshold of $20M is too low, and creates unnecessary reliance on TPP policy driven processes for projects to get deliverability. REV supports categorization of these upgrades as LDNUs, which will give projects more control on getting deliverability needed for resource adequacy contracts.

REV also requests that CAISO review the impact of the proposed increase to 10% DFAX threshold for 500 kV line overload constraints on the other ADC guidelines. ADC-2 and ADC-3 mention 5% circle which might need to be adjusted to 10% depending on if it’s a 500 kV constraint.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

REV supports CAISO’s proposal to provide conditional deliverability when transmission projects are delayed. Having this certainty will help the projects to achieve successful commercial outcomes. As stated in #5 above, REV requests that CAISO provide clarity that conditional deliverability is assured during the entire time the project is awaiting the upgrade(s) to receive FCDS. CAISO should clarify the mechanics of this proposal in its next paper. It is not clear on how and when the projects will know if it has received this conditional deliverability. REV requests that CAISO sync this part of the proposal with the Interconnection Process Enhancements initiative work, where CAISO is exploring options to provide Limited Operation Study (LOS) results 12-24 months in advance (instead of 5 months today) of project’s requested In-service dates. The scope of LOS studies is related to the RNUs, but it could be expanded to give projects updates on the deliverability status as well. REV also agrees with CAISO that, “Unlike interim deliverability, for the transmission constraint that would be mitigated by the delayed transmission project, conditional deliverability would not be lost simply because earlier queued projects come online.”

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

None

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

None

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

None

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

None

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

None

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

SDG&E encourages CAISO not to move forward with any of the options/proposals affecting ADC-C4. The elimination of ADC-C4 is not an option. Area Deliverability Constraints are valid system limitations that need to be considered in transmission system planning, especially given the large amount of resources/RA forecasted over the next 20 years. The correct allocation of deliverability for the resources will be vital for system reliability in the clean energy future. Additionally, CAISO’s proposal of adjusting mitigation cost for applicable projects from $20M to $25M or $35M is unlikely to have any major impacts given the size and scale of previous Area Deliverability Constraint mitigation. For these reasons, SDG&E recommends CAISO leave the ADNU/LDNU guidelines unchanged for this proceeding. 

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

None

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

SBE is supportive of the proposals presented by CAISO and appreciates the opportunity to provide further comments on each of the proposals.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

SEIA appreciates the opportunity to comment on the ISO’s generation deliverability assessment methodology straw proposal. SEIA is encouraged by the ISO’s responsiveness to several stakeholder-proposed reforms and comments and believes the enhancements included in the straw proposal will increase the amount of deliverability available to interconnection customers in the near-term. More specifically, SEIA supports the ISO’s proposal to extend conditional deliverability status to projects impacted by delayed deliverability upgrades or upgrades needed to mitigate n-2 contingencies that do not trigger cascading outages. SEIA maintains that the n-2 studies and mitigation requirements are overly conservative as they apply to the generation deliverability studies however the application of conditional deliverability status should ensure that n-2 contingencies only limit deliverability when reliability risks are significant.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

No comment.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

SEIA supports CAISO’s commitment to continue to monitor and update the dispatch levels used in its generation deliverability studies, as well as the methodology for establishing said dispatch levels, particularly with the implementation of the slice-of-day RA framework. The dispatch levels used will be particularly important, especially for battery storage resources, as hourly RA requirements are implemented. SEIA encourages the CAISO to continue to work with the CPUC on these issues in a public forum to ensure transparency and understanding.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

SEIA supports the CAISO proposal to increase the DFAX threshold from 5% to 10% for 500 kV line overload constraints and agrees with the ISO’s assertion that this change will better capture the generators that significantly impact high-voltage constraints.

SEIA understands the ISO’s decision to consider revisions to the treatment of local deliverability in the RA Enhancements initiative and looks forward to a more focused discussion at that time. SEIA encourages the CAISO to consider proposals like the one offered by New Leaf Energy in the IPE initiative to prioritize local RA resources in the TPD allocation process.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

Summarized above.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

SEIA supports ISO efforts to provide developers with greater control over the construction of network upgrades needed for deliverability. Changes to the ADNU/LDNU Guidelines may capture more LDCs which will benefit certain developers, but a more comprehensive review of upgrade construction options for developers is likely warranted. SEIA encourages CAISO to consider the proposals in the IPE to improve the “Option B” pathway for construction of deliverability upgrades to provide interconnection customers with more pathways to commercial operation that will also benefit system reliability.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Summarized above.

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

The Six Cities do not have specific comments on the August 29, 2023 stakeholder meeting and provide below their positions on the proposals that the CAISO has put forth in the Straw Proposal. 

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

The Six Cities do not oppose removal of the secondary system need scenario from the deliverability studies, and likewise do not oppose the inclusion of assessments related to the secondary system need in the Transmission Planning Process (“TPP”), as proposed by the CAISO.  The Six Cities request that the CAISO provide further clarification regarding the process and assumptions that will be used to perform this assessment in the TPP.  For example, the CAISO discussed use of the secondary system need scenario as a “screening” tool.  Stakeholders would benefit from an expanded explanation of the CAISO’s intended approach and its implications for the TPP. 

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

The CAISO’s proposal to retain its existing approach for dispatch levels in the deliverability studies may benefit from further explanation.  The broader issue seems to be that the CAISO’s dispatch assumptions may not be appropriately calibrated to resource type and typical utilization patterns.  If the CAISO elects not to revise its dispatch assumptions at this time, what process and criteria will the CAISO use to “monitor[] and update[] periodically such assumptions moving forward”?  Is the CAISO confident that its current assumptions are reasonable as to all resource categories, including, for example, offshore wind and storage? 

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

The Six Cities do not oppose this change, and urge the CAISO to consider if it would be appropriate to expand the application of this policy element to facilities that are lower than 500 kV?  Would such an approach expand deliverability in a way that would not jeopardize reliability if extended to some or all portions of the remainder of the CAISO grid? 

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

The Six Cities take no position at this time on the CAISO’s conclusion that N-2 studies are required for purposes of deliverability assessments under NERC reliability standards, but encourage the CAISO to complete an assessment of the costs and benefits of retaining this element of its study criteria in the deliverability assessments and provide the results of the assessment to stakeholders.  Could N-2 mitigation be more appropriately considered and addressed through reliability studies in the TPP?  Are there other ways to approach the need for N-2 mitigation in a way that does not unduly delay resources’ ability to achieve full capacity deliverability status and would be consistent with the CAISO’s interpretations of its regulatory requirements? 

The Six Cities support the CAISO’s proposal to expand the use of conditional deliverability pending completion of upgrades to address N-2 contingencies.  However, the Straw Proposal includes very little detail regarding this proposal, and the Six Cities encourage the CAISO to expand on this approach in its next policy paper.  For example, how will the CAISO determine whether and when conditional deliverability is available and to which parties it will be allocated?  Are there criteria the CAISO will use to prioritize among requests for conditional deliverability?  What will the duration of the allocation be, and is it revocable in response to any particular conditions?  Most importantly, has the CAISO done any assessment of what quantities of additional deliverability may be made available on a conditional basis as a result of this policy change? 

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

The Six Cities take no position on this issue at this time, but encourage the CAISO to evaluate and discuss the implications of the options proposed in the Straw Proposal in its next policy paper. 

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Please refer to the comments provided in response to Question No. 5 above. 

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

SCE is appreciative of the CAISO undertaking the deliverability assessment methodology review and commends the CAISO for the innovative approaches under consideration.  Deliverability continues to be a vital attribute for the economic viability of generation resources. The proposed deliverability-related refinements to address the burgeoning growth in generation development and procurement must be balanced with the need to maintain system reliability.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

Given the 2023 summer assessment indicated that the risk of resource shortages during the SSN period may be less of a concern, SCE is supportive of removing the SSN study from generation interconnection deliverability studies.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

SCE is supportive of maintaining the current dispatch level used in the deliverability studies but agrees they should be monitored and updated periodically.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

Given that a 10% distribution factor (DFAX) threshold for 500 kV line overload constraints is expected to be more practical, SCE supports this proposal.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

SCE is pleased the CAISO does not intend to change its existing practice of studying N-2 contingencies on double circuit towers.  Studying N-2 contingencies in both the reliability and deliverability studies is appropriate and it makes dealing with these contingencies in the operating horizon more manageable. Designing the system to withstand N-2 contingencies in the planning horizon increases the chances that necessary mitigations would be triggered, approved, and built in a timelier manner.

SCE acknowledges that, under the N-2 scenario, the resource can provide deliverability in most circumstances. However, SCE is concerned with the CAISO’s proposal that additional generation projects would be eligible for a “conditional deliverability” status during the development period of the transmission upgrade necessary to mitigate the N-2 contingency, assuming that no other constraints are binding.  SCE requests the CAISO explain how the CAISO can award “conditional deliverability” for a project that is not physically deliverable until an upgrade is completed.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

SCE supports raising the cost threshold in the Area Constraint guideline for ADC-C4 to $35M in current dollars as there have historically been triggered upgrades that could have been classified as LDNUs that were instead classified as ADNUs and then removed in the Phase 2 studies because the interconnection customers all chose Option A to not pay for ADNUs. Having such a low monetary threshold for ADNUs excludes a lot of capacity producing upgrades that may be affordable through cost sharing by the multiple generation projects triggering the upgrade.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

As stated in the CAISO’s August 29 presentation, the purpose of the CAISO’s deliverability methodology is “to test that the transmission system can reasonably ensure that resource adequacy capacity can be delivered to load during stressed system conditions.”  Although SCE is supportive of the CAISO’s efforts to properly identify potentially latent deliverability within the transmission system to be awarded to viable generation projects, SCE is concerned with the CAISO awarding “conditional deliverability” without the existence of the required physical infrastructure (i.e., network upgrades)  unless there is a reasonable degree of confidence that the generating unit will continue to provide reliability benefits during the interim period. Seemingly, the CAISO’s proposal to operate the grid with “conditionally deliverable” resources could result in the CAISO knowingly managing the grid with insufficient deliverable resources available to meet the Resource Adequacy (RA) requirements.  Any conditional deliverability proposal should not undermine the core structure of the RA process.  Thus, while some deliverability accommodations can and should be made, there must be some understanding of the reliability impacts of these accommodations.

For example, the CAISO’s proposal to allow conditional deliverability while an N-2 condition (Topic No. 5 above) is addressed means that the unit will provide deliverability in all but rare circumstances, and thus a temporary deliverability accommodation seems reasonable.  On the other hand, there should be some additional consideration for delays in upgrades.  For example, perhaps a deliverability accommodation would be reasonable if the upgrade was not necessary in the base case but was only needed to resolve a contingency or some other infrequent event.

SCE requests the CAISO do the following:

• Explain how and through what study/analysis “conditional deliverability” is identified/created
• Describe what is entailed in the risk assessment to proceed with the assignment of “conditional deliverability” to a project and how the risks are mitigated across all potentially affected parties
• Explain how the CAISO can award conditional deliverability” for a project that is not physically deliverable until an upgrade is completed
• Clarify if the CAISO is proposing to operate the grid for an interim period knowing there are insufficient deliverable resources to meet Resource Adequacy requirements   
• Confirm that conditional deliverability satisfies the CAISO and CPUC requirements toward RA compliance
• Confirm that conditional deliverability is issued once, cannot be revoked, and does not require subsequent applications
• Clarify the differences between conditional deliverability and FCDS (outside of the way it is obtained)
• Clarify the CAISO proposes to provide conditional deliverability based on the original schedules of deliverability network upgrades (assuming the needed reliability network upgrades are in-service)

1. Please provide a summary of your organization’s comments on the Generation Deliverability Methodology Review stakeholder call.

Terra-Gen, LLC. (Terra-Gen) supports CAISO’s efforts to consider Generation Deliverability Methodology reforms. Terra-Gen appreciates the opportunity to comment on CAISO’s Straw Proposal (Proposal) that provides critical reforms necessary to enable the successful development of needed generation and storage resources. As acknowledged in CAISO’s Proposal and stakeholder meetings, refinements to its deliverability assessment methodology are imperative to the facilitation of California’s ambitious policy goals and vital reliability requirements that have driven rapid growth in generation development and procurement needs, and increased diversification of the resource fleet. Terra-Gen highlights that deliverability is a key aspect in the successful development of new generation and storage resources.

Terra-Gen is supportive of the Proposal’s overall refinements and most of the changes presented by the CAISO that represent helpful modifications to the current CAISO methodology. Terra-Gen highlights its support for the concept of “Conditional Deliverability” as outlined in the Proposal as a beneficial step in the right direction. However, Terra-Gen notes concerns regarding the n-2 contingency item and the timing related to the Conditional Deliverability concept. Terra-Gen also requests additional clarification as outlined below.

Terra-Gen advises that CAISO’s proposed approach to n-2 contingency risk appears to be overly conservative and results in unnecessarily precluding highly reliable resources from achieving deliverability status and interconnecting to the grid. Terra-Gen understands that NERC reliability standards do not require CAISO to apply the n-2 mitigation requirements in its deliverability studies. Rather, NERC only requires that all credible N-2 contingencies be studied as part of reliability studies performed in the interconnection process and there are not similar requirements for deliverability studies. Therefore, Terra-Gen recommends that CAISO instead address n-2 related reliability upgrades separately in the reliability portion of interconnection studies, which are subject to NERC standards. Terra-Gen believes that this approach is more reasonable to enable the benefits associated with achieving greater resource development while also addressing n-2 risk through the interconnection reliability studies and that the approach presents a very low risk to reliability.

Terra-Gen reiterates its appreciation for CAISO’s overall efforts to explore reforms to its Generation Deliverability Methodology and the opportunity to provide input.

2. Provide a summary of your organization’s comments on the proposed removal of secondary system need from generation interconnection deliverability studies, as described in the straw proposal.

Terra-Gen supports the removal of the Secondary System Need (“SSN”) study scenario as described in the Proposal. The removal of the SSN is reasonable and appropriate because there is minimal risk of stressed conditions and resource shortages during the SSN window, as evidenced by CAISO’s analysis included in its latest Summer Assessment.

3. Provide a summary of your organization’s comments on the maintaining the methodology for determining dispatch levels, as described in the straw proposal.

Terra-Gen does not support or oppose the Proposal for maintaining the current resource generation dispatch assumptions. CAISO’s issue paper and Proposal has provided helpful background information and explanation of its current methodology and reasoning surrounding existing resource dispatch assumptions in its deliverability studies.

Terra-Gen recommends CAISO consider providing an initial review of the potential interactions with the CPUC’s Slice-of-Day (SOD) hourly Resource Adequacy (RA) reform framework and its Generation Deliverability Methodology. CAISO should prioritize discussion around the implications of potentially incorporating the CPUC’s SOD hourly resource values into its deliverability study methodology to help inform commercial considerations by Load Serving Entities (LSE) and resource developers. Terra-Gen believes that CAISO should not delay initiating a review of the considerations of moving to an hourly RA framework as it relates to the Generation Deliverability Methodology. CAISO’s effort would assist stakeholders’ understanding and facilitate informed participation in future RA Enhancements initiative efforts.

4. Provide a summary of your organization’s comments on the proposed increase to 10% DFAX threshold for 500 kV line overload constraints, as described in the straw proposal.

Terra-Gen supports increasing the DFAX threshold to 10% for 500 kV line constraints as described in the Proposal.

5. Provide a summary of your organization’s comments on the proposed changes to treatment of n-2 studies and mitigation requirements, as described in the straw proposal.

Terra-Gen advises that CAISO’s proposed approach to n-2 contingency risk appears to be overly conservative and results in unnecessarily precluding highly reliable resources from achieving deliverability status. Terra-Gen understands that NERC reliability standards do not require the CAISO to apply the n-2 mitigation requirements in its deliverability studies. Rather, NERC only requires that all credible n-2 contingencies be studied as part of reliability studies performed in the interconnection process and there are not similar requirements for deliverability studies. Terra-Gen notes that system reliability is also addressed by the CPUC’s RA program and CAISO’s Transmission Planning Process (TPP).

Terra-Gen recommends that CAISO continue to address n-2 related reliability upgrades separately in the reliability portion of interconnection studies, which are subject to NERC standards. If CAISO is concerned that insufficient reliability upgrades will be identified there, additional reliability test scenarios could be added to this portion of the generation interconnection study process. This approach would align more closely with the approach that other ISO/RTO regions utilize to address n-2 risks. Notably, CAISO’s reliability study assesses the n-2 risk using more realistic generation dispatch assumptions, which will trigger fewer upgrades. By addressing the n-2 risk through the reliability portion of interconnection studies, and not the deliverability portion, CAISO would enable more resources to obtain deliverability status and be successfully developed, further helping to address current resource shortages and RA scarcity conditions that threaten reliability and increase end-use customer costs.

Terra-Gen believes that this approach is more reasonable to enable the benefits associated with achieving greater resource development while also addressing n-2 risk through the interconnection reliability studies and that the approach presents a very low risk to reliability. If CAISO is unwilling to explore the suggested alternative, then it should provide better justification for the proposal for the continued application of NERC n-2 reliability standards under its deliverability studies.

6. Provide a summary of your organization’s comments on revising the ADNU/LDNU Guidelines, as described in the straw proposal.

Terra-Gen supports eliminating the cost threshold under the Area Constraint guideline for ADC-C4 (Option 3).  The cost threshold for projects that qualify for ADNUs under ADC-C4 should be raised to at least $50 million, which is already covered by ADC-C3; therefore, ADC-C4 is unnecessary. This will enable developers to have more control over upgrades that are needed to achieve deliverability status without being delayed by waiting for ADNU upgrades to be developed through the CAISO TPP.

7. Provide a summary of your organization’s comments on the proposed conditional deliverability based original schedules during delayed deliverability upgrades, as described in the straw proposal.

Terra-Gen supports the direction of the Proposal for providing “Conditional Deliverability” to impacted resources during delays to identified deliverability upgrades. However, Terra-Gen also notes concerns regarding the n-2 contingency item as related to the Proposal for Conditional Deliverability. CAISO’s Proposal appears to provide for the potential Conditional Deliverability concept to be applied for extended periods of time while identified transmission projects are developed and built to provide the required mitigation. The length of time expected for average transmission project development, permitting, and construction can last from seven to ten years. CAISO’s Proposal will provide eligibility for the proposed Conditional Deliverability concept for an extended period that could last nearly a decade or more in some circumstances. This fact and the proposed approach reveal that CAISO itself must believe that any reliability concern or risk of n-2 contingencies impacting deliverability is a very low probability, otherwise the CAISO would not be willing to include the so-called “risk-based” approach in its Proposal for allowing this Conditional Deliverability concept. Therefore, Terra-Gen reiterates it argument that CAISO should not apply the n-2 contingency mitigation in its deliverability studies and should only include it in the reliability studies of the interconnection study process, as previously described in the response to Question #5 above.

Terra-Gen also requests CAISO provide clarification on how it intends to apply the proposed Conditional Deliverability policy and related implementation details on the following topics and questions:

• During the stakeholder meeting, in response to a stakeholder question, CAISO stated that this policy would apply to queue Cluster 14 (C14), C15, and later queue clusters.
  • The CAISO should clarify the eligibility for the proposed Conditional Deliverability option.

• During the stakeholder meeting, in response to a stakeholder question, CAISO indicated that Conditional Deliverability would not be revoked or affected by extensions in delays to necessary transmission upgrades.
  • CAISO should clarify the Proposal to confirm that additional delays to transmission projects affecting resources would not impact the proposed allowance for Conditional Deliverability.

• CAISO should provide more clarity on the concepts of Interim Deliverability and Conditional Deliverability and how these interrelated concepts interact.
  • Developers need to be informed as to whether projects’ Full Capacity Deliverability Status (FCDS) are being held up due to an n-2 condition (which would be resolved by Conditional Deliverability) and/or an n-1 condition (which may require an Interim Deliverability designation). 
  • CAISO should provide an example(s) to demonstrate the intended implementation of the proposal for Conditional Deliverability and how it would interact with the current Interim Deliverability concept.

• CAISO should clarify if it proposes to generally apply the more relaxed Conditional Deliverability test in each interconnection study process or not.
  • If so, such an approach could result in substantially more Transmission Plan Deliverability (TPD) capacity becoming available from the existing system as well as recently approved TPP transmission upgrades for allocation, thus enabling more resources to achieve commercial operation.
  • Alternatively, if CAISO proposes to continue to apply the current, highly restrictive deliverability test in each interconnection study process it should clarify this position in its Proposal.
    • If so, such an approach would lead to a much smaller amount of TPD capacity becoming available to allocate among projects based on expected transmission construction schedules at that time.
    • If this is the case, it appears CAISO would then only provide Conditional Deliverability status if/when those schedules become delayed during the development period of the transmission upgrade, which is an arbitrary application of reliability standards based on non-reliability circumstances.