Comments on 1/29 Kick-off Meeting

1. Submission title

Transmission Access Charge (TAC) Structure Enhancements

2. Has this issue previously been submitted? If yes, please provide a reference.

This issue was considered in the 2016-2018 TAC Structure Review initiative, resulting in a Draft Final Proposal in 2018. This initiative received broad support at the time, including from the CAISO Department of Market Monitoring (DMM), California’s three largest investor-owned utilities, municipal utilities, independent transmission developers, retail marketers, and the California Public Utilities Commission.

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

The current volumetric-only TAC structure does not accurately reflect cost-causation principles and utilization of the transmission system, resulting in inequitable distribution of costs and inefficient system planning. As large loads require system upgrades to interconnect to the California transmission system, and to avoid disproportionate impacts to other retail customers, the CAISO must ensure transmission costs paid by all customers accurately reflect system costs. A hybrid TAC structure using both a volumetric component and peak demand component supports the efficient and equitable expansion of the transmission system and supports integration of flexible loads by incentivizing customers to adjust use during periods of high system demand.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The proposed TAC Structure Enhancements initiative would review the existing volumetric TAC design and assess the equity of cost allocation under the current structure and under a hybrid TAC structure. The initiative should also consider the influence that TAC structures have on transmission investment and cost allocation as large load customers interconnect to the CAISO grid.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

The current volumetric TAC structure does not create an incentive to reduce electricity consumption during periods of high system demand. This likely leads to additional transmission investment that would not be required if customers are incentivized to reduce use of the transmission system during peak demand hours. Implementing a hybrid TAC structure would realign incentives around system peak hours and reduce the need for additional resource builds that may be required under a volume-based TAC structure.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

The 2025 SB 100 Joint Agency Report[1] demand forecast shows dramatic load growth over the 2026-2045 period driven by fuel switching and interconnection of large loads. By the end of the forecast horizon, California loads switch from summer-peaking to winter-peaking. As additional customers look to charge their electric vehicles and run their heat pumps during peak hours, and additional large loads come online, it is critical to address the incentives to use energy during peak demand periods.

[1] https://www.energy.ca.gov/sb100

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

Solutions were developed during the 2016-2018 TAC Structure Review initiative. We recommend using the 2018 Draft Final Proposal as a starting point for this TAC Structure Enhancements initiative.

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

Energy-Only (EO) Resources Seeking Deliverability   

2. Has this issue previously been submitted? If yes, please provide a reference.

Yes, California Community Choice Association (CalCCA) submitted this issue in its March 12, 2025, comments to the 2025-2026 Transmission Planning Process (TPP) Draft Study Plan.^[1] As a result, the CAISO included this issue in its Interconnection Process Enhancements (IPE) 5.0 and developed a proposal to allow operational EO projects to seek deliverability through the power Purchase Agreement (PPA) group or conditional allocation group.^[2]

CalCCA appreciates progress made on this issue but remains concerned that the California Independent System Operator’s (CAISO) forthcoming final proposal will not result in a viable pathway for EO projects to obtain deliverability. This is because the Final Proposal is expected to limit deliverability allocations to EO projects in which there is already available transmission plan deliverability (TPD), and not where deliverability network upgrades are necessary to make the projects deliverable. Given existing deliverability is scarce,^[3] the CAISO’s proposal may have limited usefulness if commercially operational EO resources are located in areas without existing TPD. For these reasons, the CAISO should commit to exploring enhancements necessary to make EO resources fully deliverable.  

[1]           CalCCA Comments on the Draft Study Plan and February 26, 2025, Stakeholder Meeting (March 12, 2025), https://stakeholdercenter.caiso.com/Comments/AllComments/173f349e-e423-4ce0-8311-f976a29d85b6#org-421dd98b-5b20-4ac2-8c96-8f6327f2077c.

[2]           CAISO, Interconnection Process Enhancements 5.0 – Addendum to the Final Proposal (Feb. 9, 2026), https://stakeholdercenter.caiso.com/InitiativeDocuments/Presentation-Interconnection-Process-Enhancements-5-0%E2%80%93Addendum-to-the-Final-Proposal-Feb-09-26.pdf.

[3]           The CAISO Points of Interconnection Heatmap shows that available TPD in the Cluster 15 Phase 1 scenario is extremely limited, https://www.caiso.com/poi-heatmap/.

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

Resources must be studied for deliverability to ensure that the electricity produced at its location can be delivered to the aggregate of load. TPD allocations are a critical part of project development because resources must obtain TPD to provide resource adequacy (RA) and meet California Public Utilities Commission (CPUC) procurement obligations. Available TPD is scarce, with a majority of substations having no deliverability to allocate to new projects without upgrades to existing infrastructure. These limitations, if left unaddressed, have the potential to jeopardize the state’s ability to bring new resources online to support reliability requirements established in the Resource Adequacy (RA) and Integrated Resources Planning (IRP) processes and clean energy goals established by statute.

The CAISO should therefore enhance the policy adopted in IEP 5.0 to remove barriers to using the proposed pathway, including limitations on available TPD. The CAISO should explore future pathways for EO projects behind constraints to seek deliverability, particularly where projects have made commitments with LSEs or where projects are aligned with local regulatory authority policy needs. This will ensure sound investments in deliverability network upgrades that support reliability and policy objectives.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

This initiative would consider enhancements to ensure the pathway for converting an EO project to a deliverable project can be used. It would evaluate the policy adopted in IPE 5.0 and determine what barriers to using the proposed pathway, including limitations on available TPD, are preventing EO projects from seeking and obtaining deliverability. The CAISO would explore future pathways for EO projects behind constraints to seek deliverability, particularly when projects have made commitments with LSEs or when projects are aligned with local regulatory authority policy needs.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

Deliverable resources are necessary to support forthcoming IRP and RA reliability needs. The CPUC has recently identified a 6,000 megawatts (MW)^[1] reliability need between 2029-2032 and has ordered CPUC-jurisdictional LSEs to procure new resources to meet this reliability need.^[2] Capacity eligible to satisfy the CPUC’s procurement order must be deliverable or paired with a deliverable resource. In addition, RA capacity has been scarce for the last few years. While recent build has helped, load growth may account for all of the recently built capacity, requiring more RA to be procured. Given a choice between pursuing uncertain imports for RA, building a new resource, or contracting with an existing EO resource to provide incentive to pursue network upgrades to become deliverable, more competition for providing RA will benefit consumers in reaching their reliability goals affordably. In fact, it may be that converting an EO facility to fully deliverable is the quickest, most certain, and most cost-effective way to meet RA needs since the resource is already in California, is operational, and has an EO contract to address all costs except the costs of network upgrades. 

[1]           The need is denominated in Net Qualifying Capacity and since the resources are likely to come from non-emitting resources, the amount of installed capacity will be significantly greater. 

[2]           Proposed Decision Requiring 2029-2032 Electric Resource Procurement And Transmitting Portfolios For 2026-2027 Transmission Planning Process, R.25-06-019 (Feb. 26, 2026) at 2: https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M600/K854/600854771.pdf.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

This issue should be addressed urgently in the next IPE initiative. The CPUC has recently identified a 6,000 MW reliability need between 2029-2032 and has ordered CPUC-jurisdictional LSEs to procure new resources to meet this reliability need.^[1] Capacity eligible to satisfy the procurement order must be deliverable or paired with a deliverable resource. Likewise, RA requirements also require resources to be fully deliverable to count.

A viable approach to converting EO resources to deliverable resources could help expand and expedite opportunities for developers to finance and construct projects without a TPD allocation. Constructed and operational projects may be more viable than earlier stage projects under development, may be able to provide deliverable capacity more quickly than earlier stage projects, and should be allowed to compete against other projects in the interconnection intake process and TPD allocation process to contribute to the state’s RA requirements.  

[1]           Ibid.

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

The CAISO should evaluate TPD requests from EO projects through the process established in IPE 5.0 to determine whether these requests typically result in deliverability allocations or whether enhancements to the pathway are necessary to make it useful. In addition, the CAISO should examine the desire of EO resources to transition to full deliverability and the barriers that the current process presents to doing so.

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

Transmission Access Charge (TAC) Structure Enhancements

2. Has this issue previously been submitted? If yes, please provide a reference.

Yes, this issue has been previously discussed through the CAISO Policy Initiative Process, where it received support from numerous stakeholders. It was subsequently formally submitted by stakeholders for further consideration, including the California Department of Water Resources' State Water Project (CDWR-SWP).

CAISO first initiated formal examination of potential changes to the Transmission Access Charge (TAC) beginning in 2015–2016, through the Transmission Access Charge Options Initiative and the Review Transmission Access Charge Wholesale Billing Determinant Initiative. Stakeholders expressed concerns that the existing purely volumetric TAC, assessed on each MWh of metered internal end-use load and exports, no longer reflected transmission system cost causation, given changes in system usage, increasing reliance on flexible resources, and growing divergence between energy consumption and contribution to coincident system peak.

Building on those efforts and to address stakeholder requests for a comprehensive review, CAISO launched the Transmission Access Charge Structure Enhancements Initiative in 2017 to conduct a comprehensive technical and policy evaluation of alternative TAC billing determinants. The initiative examined whether continued reliance on a volumetric-only charge appropriately aligned transmission cost recovery with the drivers of transmission investment and usage, and whether incorporating coincident peak demand and other non-energy-based factors could improve cost causation, equity among load-serving entities, and consistency with other CAISO cost allocation frameworks, including Resource Adequacy capacity obligations.

The initiative culminated in a Draft Final Proposal issued in September 2018, which recommended a hybrid TAC structure that would retain a volumetric component while introducing a demand-based element tied to the coincident system peak[1]. The proposal also evaluated whether the billing determinant for internal load should be modified to account for load offset by distributed energy resources, recognizing that behind-the-meter generation reduces volumetric energy consumption without necessarily reducing contribution to system peak or long-term transmission investment needs. CAISO’s analysis concluded that a hybrid approach would better align TAC recovery with transmission cost drivers, improve rate stability, and reduce cost shifts among transmission users.

The Draft Final Proposal reflected extensive stakeholder engagement and technical analysis and received broad support from a wide range of stakeholders, including CAISO’s Department of Market Monitoring, the California Public Utilities Commission, investor-owned utilities, municipal utilities, and customer and public power interests. Rather than advancing the proposal for Board consideration, CAISO placed the initiative on hold in late 2018 to prioritize the development and implementation of the Extended Day-Ahead Market (EDAM), citing the need to ensure consistent treatment of transmission cost recovery as the market footprint expanded. The initiative was neither rejected nor withdrawn, and no other policy initiative superseded it.

In the 2020 Final Policy Initiatives Catalog, the initiative was included under Section 5: Initiatives Currently Underway and Planned as a committed item, with anticipated Board consideration identified for 2020. The catalog description reiterated the technical scope of the initiative, including evaluation of whether the TAC should remain purely volumetric or incorporate other factors such as peak demand, and whether the internal load billing determinant should be modified to account for load offset by distributed energy resources[2]. CAISO stated that the Draft Final Proposal was complete but on hold pending policy development for the Extend Day-Ahead Markets to EIM Entities initiative to ensure consistent treatment of transmission cost recovery across an expanded market footprint.

In 2021, CAISO again carried TAC Structure Enhancements forward in the 2021 Policy Initiatives Catalog under Section 5: Initiatives Currently Underway and Planned, maintaining its committed status and continuing to describe the draft final proposal as complete but on hold pending policy development for the Extend Day-Ahead Markets to EIM Entities policy. CAISO’s Updated 2021–2023 Policy Initiatives Roadmap also listed TAC Structure Enhancements as a named roadmap item, demonstrating that CAISO continued to view the TAC billing determinant questions as a relevant and unresolved market policy design topic during this period, rather than as an issue that had been resolved on the merits.

Following this period, TAC Structure Enhancements was included in the 2022[3] and 2023[4] Policy Initiatives Catalogs, but was moved to Section 7: Discretionary Initiatives, under Section 7.1: Energy and Ancillary Services Markets. In these catalogs, CAISO continued to describe the initiative’s technical scope, whether the volumetric TAC structure should be retained or modified to include peak demand, and whether the billing determinant for internal load should be adjusted to account for load offset by distributed energy resources, and reiterated that the draft final proposal was complete and on hold pending policy development of the Extend Day-Ahead Markets to EIM Entities initiative.

Consistent with this designation, the TAC Structure Enhancements Initiative was not included in the Final 2022–2024 Policy Initiatives Roadmap, reflecting CAISO’s continued deferral of TAC structural changes while EDAM-related policy development was underway. Importantly, exclusion from the Roadmap did not reflect a substantive rejection of the Draft Final Proposal or a determination that the underlying cost causation issues had been resolved.

CAISO subsequently implemented a new submission-based process for the 2024 Annual Policy Initiatives Catalog and Roadmap, under which stakeholders were required to submit new or renewed proposals for CAISO consideration. The TAC Structure Enhancements Initiative was not submitted during that cycle and therefore did not appear in the 2024 Catalog. No technical reassessment of the Draft Final Proposal or its underlying cost causation analysis was conducted.

In 2025, CDWR-SWP submitted a proposal to revisit and restart the TAC Structure Enhancements Initiative, citing the continued relevance of the technical issues evaluated in the 2016–2018 process, including misalignment between volumetric charges and coincident peak demand and the increasing importance of load flexibility, demand response, and efficient use of existing transmission infrastructure. CAISO did not include the initiative in the 2025 Policy Initiatives Catalog[5] and instead routed it to the 2025–2026 Transmission Planning Process (TPP) as an infrastructure-related item. At the September 25, 2025, TPP stakeholder meeting, CAISO dismissed the proposal, stating that the issue had been considered in 2018, placed on hold to enable EDAM development, and that changes to the TAC structure were no longer necessary because behind-the-meter solar generation had stabilized. This dismissal did not include a technical reassessment of the Draft Final Proposal, nor did it address the initiative’s original focus on coincident peak demand, rate design, or cost allocation principles.

In December 2025, Joint Commenters representing CDWR-SWP, Bay Area Municipal Transmission Group (BAMx), and the State Water Contractors (SWC) submitted a joint letter to the CAISO Board of Governors and the WEM Governing Body requesting directions to CAISO staff to revive the TAC Structure Enhancements initiative through a transparent stakeholder process[6]. The Joint Commenters emphasized that the initiative had already undergone extensive technical analysis and stakeholder vetting during the 2016–2018 period, resulting in a Draft Final Proposal that was never presented for Board consideration, and that subsequent procedural deferrals did not constitute a substantive evaluation of whether the existing volumetric TAC remains aligned with transmission cost causation, coincident peak demand, or evolving system usage. In addition, CDWR-SWP and other Joint Commenters submitted detailed comments on the 2026-2028 Annual Policy Initiatives Roadmap[7], explaining that TAC Structure Enhancements raises fundamentally market policy questions related to rate design and cost allocation, rather than infrastructure planning issues, and therefore falls squarely within the scope of the Market Policy Catalog and Roadmap process. The Joint Commenters requested that CAISO initiate a dedicated stakeholder process to reassess the Draft Final Proposal in light of current system conditions, rather than relying on continued deferral or summary dismissal, to ensure that transmission cost recovery remains aligned with cost causation, market efficiency, and California’s evolving clean energy and load flexibility objectives.

While TAC-related items were noted as appropriate for the Infrastructure Policy process during the January 26, 2026, kick-off meeting, TAC Structure Enhancements fall into a gray area. The initiative is fundamentally about rate design and cost allocation, which are core market policy elements. For this reason, CDWR-SWP believes it is important to submit this proposal through both the Market Policy Catalog and Roadmap and Infrastructure Policy Catalog and Roadmap processes to ensure these considerations receive proper attention.

[1] “Modifications to TAC Structure: Hybrid Billing Determinant Proposal.” Transmission Access Charge Structure Enhancements Draft Final Proposal, September 2018, pp. 9-18, Section 7, https://stakeholdercenter.caiso.com/InitiativeDocuments/DraftFinalProposal-TransmissionAccessChargeStructureEnhancements.pdf    

[2] CAISO, 2020 Final Policy Initiatives Catalog, “Section 5: Initiatives Currently Underway and Planned – Transmission Access Charge Structure Enhancements.” pp. 14, https://www.caiso.com/documents/2020finalpolicyinitiativescatalog.pdf

[3] CAISO, 2022 Revised Policy Initiatives Catalog, “Section 7.1.15: Discretionary Items - Transmission Access Charge Structure Enhancements.” pp. 18, https://stakeholdercenter.caiso.com/InitiativeDocuments/2022RevisedDraftPolicyInitiativesCatalog.pdf

[4] CAISO, 2023 Final Policy Initiatives Catalog, “Section 6.1.14: Discretionary Items - Transmission Access Charge Structure Enhancements.” pp. 26, https://stakeholdercenter.caiso.com/InitiativeDocuments/Final2023PolicyInitiativesCatalog.pdf

[5] CAISO, 2025 Annual Policy Initiatives Catalog, “Appendix B: Non-Catalog Items.” https://stakeholdercenter.caiso.com/InitiativeDocuments/Appendix-B-Non-Catalog-Items.xlsx

[6]  Joint ISO Board of Governors and WEM Governing Body General Session, “Joint Public Comment Letter - Briefing on Policy Roadmap.” https://www.caiso.com/documents/joint-public-comment-letter-briefing-on-policy-roadmap-dec-2025.pdf

[7] CAISO, 2026-2028 Annual Policy Initiatives Roadmap, “Joint Commenters: Submitted on behalf of

California Department of Water Resources – State Water Project (CDWR), Bay Area Municipal Transmission Group (BAMx), and State Water Contractors (SWC).” https://stakeholdercenter.caiso.com/Comments/AllComments/efa23f79-fc99-4e24-ac86-eded29e74d06#org-338b2919-b344-43ed-a584-6cfe8f3c24d3

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

CDWR-SWP believes that TAC Structure Enhancements will address certain areas of market inefficiencies related to transmission usage and cost allocation, as previously identified by CAISO in the Draft Final Proposal for the 2018 TAC Structure Enhancements.

CAISO noted two fundamental issues: (1) how to measure transmission usage, and (2) where to measure it. Since 2001, CAISO has used a volumetric-only approach to allocating TAC costs. However, changes in California’s resource mix, load patterns, and the overall evolution of the electric system have reduced the effectiveness of this methodology in reflecting cost causation, system utilization, and the benefits of the transmission system.

CAISO concluded that a hybrid approach, combining both coincident peak-demand and volumetric measurements, better captures the transmission system's dual functions, energy delivery and capacity/reliability—while aligning cost allocation with the benefits users receive. The initiative therefore addresses the policy question of whether the current volumetric-only TAC methodology remains appropriate or should be enhanced to a hybrid framework that more accurately reflects usage, system benefits, and investment drivers.

CAISO determined that the existing volumetric-only Transmission Access Charge may no longer accurately reflect transmission cost causation or system utilization given significant changes in California’s resource mix, load patterns, and overall grid operations. CAISO therefore identified the need to reexamine both how transmission usage is measured and how transmission costs are allocated among users.

Based on this assessment, CAISO concluded that a hybrid TAC structure combining volumetric and coincident peak demand components would better align transmission cost recovery with the system’s energy delivery, capacity, and reliability functions. CAISO found that retaining a volumetric component continues to reflect energy-delivery benefits, while adding a peak-demand component better captures cost drivers associated with system peak conditions and reliability needs. Compared to a volumetric-only approach, a hybrid framework more accurately reflects transmission usage, cost drivers, and the benefits users receive from the transmission system.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The scope of the TAC Structure Enhancement initiative addresses several elements of the existing TAC assessments, as CAISO noted in the Draft Final Proposal for the 2018 TAC Structure Enhancements.

Through this initiative, CAISO would evaluate whether the existing transmission access charge billing determinant should be modified to reflect better customer utilization of, and benefits derived from the transmission system, including how load offset by distributed generation is treated. The initiative would also assess whether the current volumetric-only TAC structure accurately reflects the causation of transmission costs and customer benefits by examining alternative approaches, including demand-based, time-differentiated, volumetric, or hybrid billing structures.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

CDWR-SWP believes that a Hybrid TAC with charges for both Volumetric and Peak Demand would impact infrastructure development and system reliability as follows:

1. Utilities would increasingly move load away from Peak Demand to reduce transmission costs.
2. Lowering Peak Demand would reduce the need for new transmission infrastructure development to accommodate increasing load forecasts.

System Reliability would increase as less Peak Demand reduces the physical strain on current transmission lines, leading to decreased maintenance and replacement costs.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

If the TAC Structure Enhancement initiative is not addressed in a timely manner, it could have direct economic implications for ratepayers and load-serving entities. Entities with flexible load profiles, in particular, may benefit from a Hybrid TAC structure that better reflects actual system usage and peak cost drivers. Delays in reform could therefore perpetuate cost allocation outcomes that do not fully align with evolving system conditions or policy direction.

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

In the Draft Final Proposal for the TAC Structure Enhancements Initiative 2018, the CAISO provided background on prior and current transmission costs and forecasted different Hybrid TAC balances for estimated future costs through 2022[1]. The Draft Final Proposal is the latest, most thorough, and richest public data set and analysis that exists at this point focusing only on the CAISO Market. The review in the Proposal focuses on improving cost allocation to better reflect both energy delivery and reliability functions of the transmission system. The current volumetric-only approach is being evaluated against a hybrid billing determinant that combines volumetric (MWh) and peak demand (MW) measurements. To respond to question 7, CDWR-SWP has outlined the key design elements, analysis, and data sources from the Proposal:

Key design elements include:

• Splitting the High Voltage Transmission Revenue Requirement (HV-TRR) using a system-wide annual gross load factor.
• Using 12-month coincident peak (12CP) measurements for the demand component.
• Maintaining the point of measurement at the end-use customer meter.

The review uses multiple datasets and analytical methods to validate the hybrid approach:

• Data Sources:
  • Historical hourly load data (2014–2017) and monthly coincident peaks for 12CP calculations.
    • Filed annual HV-TRR values (e.g., $2.165 billion for 2017) and PTO-specific gross load forecasts.
• Analysis Performed:
  • Load Factor Calculation: Determines the split between volumetric and demand charges based on average vs. peak load.
  • Sensitivity Testing: Compares bifurcation ratios (40/60 to 60/40) and peak measurement frequencies (1CP, 4CP, 12CP).
  • Historical Variability: Confirms low volatility (<3.5% variance) in annualized 12CP demand, supporting a one-year historic period without weather normalization.

The following figures give one example of the coincident peak measurement frequency scenario for a hybrid TRR split that is equally 50% volumetric and 50% peak demand. It looks at 11 utility areas in the CAISO BAA and for 2018 - 2022 forecasts their gross hybrid TAC payment amounts, the gross amount difference between those hybrid payments and the current TAC payments along with the percentage differences between them.  

Figure 1: Proposed TAC Charges for California Utilities using Hybrid TRR Split

50% Volumetric – 50% Peak Demand[2]  

Figure 2: Differences for California Utilities between Proposed Hybrid TAC and Existing TAC

in Dollars (top) and Percentages (bottom)[3]

Furthermore, it is important to review the implementation of a hybrid TAC in other markets by reviewing the rollouts, refinements, and impacts/benefits of the implementation. In the Issue Paper for Review Transmission Access Charge Structure Enhancements Initiative from 2017, the CAISO summarizes different approaches to transmission charges for the Independent System Operators (ISOs) and Regional Transmission Owners (RTOs) in the United States: CAISO, NYISO, MISO Multi Value Projects (MVPs), SPP Network Integration Transmission Service (NITS), ISO-NE NITS, MISO NITS, ERCOT (4 summer months), and PJM NITS[4].

Looking into how other markets have implemented hybrid TAC, seeing the impacts of changing their TACs, and updating the TAC data at this time shows a longer history of their implementation and would be informative for stakeholders and beneficial for further discussions. To respond to question 7, CDWR-SWP has outlined the key design elements and summary of other markets rates from the Paper:

Key design elements include:

• A very high-level overview of how transmission charges are structured in other ISOs and RTOs for network transmission service so that it is intelligible and useful for the scope of this initiative.

The review uses no datasets or analytical methods. CAISO says:

• “Providing a comprehensive discussion of every detail of their rate designs would span hundreds of pages.”
• “Different ISOs/RTOs may provide different market services (e.g., network integration service, firm point-to-point service, non-firm service), so a direct apples-to-apples comparison with the CAISO is challenging.”
• “These challenges are compounded by highly varying terms and definitions used in the various RTOs.”

The Figure 3. Summary of ISO/RTO approaches to transmission charges has a breakdown to compare the Volumetric ISO/RTOs and the Demand ISO/RTOs:

• The basis of the charge.
  • Either a Volumetric charge of MWh/Gross Load, or a Demand Charge which is divided into Monthly peak, Annual peak, or Variable.
• Examples of the ISO/RTOs that use each type of basis.
  • Network Integration Transmission Service (NITS) allows an electric transmission customer to integrate, plan, economically dispatch and regulate its network reserves in a manner comparable to that in which the Transmission Owner serves Native Load customers.
  • Multi Value Projects (MVPs) are regional transmission projects designed to support public policy, provide economic value, or provide economic value and reliability.
• The Intent of the charges.
  • Correlation with either beneficiaries for Volumetric charge or cost causation for demand charge
• The Pros of using the different types of charges.
• The Cons of using the different types of charges.

The Figure 3. Summary of ISO/RTO approaches to transmission charges separates the ISO/RTOs based on whether they use a Volumetric charge of MWh/Gross Load, or a Demand Charge which is divided into Monthly peak, Annual peak, or Variable.

Figure 3: Summary of ISO/RTO Approaches to Transmission Charges[5]

[1] “Appendix B – Hybrid billing determinant proposal TAC cost impact modeling analysis with

additional sensitivities.” Transmission Access Charge Structure Enhancements Draft Final Proposal, September 2018, pp. 51, https://stakeholdercenter.caiso.com/InitiativeDocuments/DraftFinalProposal-TransmissionAccessChargeStructureEnhancements.pdf

[2] “Coincident Peak measurement frequency scenarios Scenario: 12CP frequency (12 demand measurements, Hybrid TRR split: 50% Volumetric - 50% Peak Demand) Proposed TAC Charge for Hybrid - Gross Load ($ million).” Transmission Access Charge Structure Enhancements Draft Final Proposal, September 2018, pp. 52, Appendix B, https://stakeholdercenter.caiso.com/InitiativeDocuments/DraftFinalProposal-TransmissionAccessChargeStructureEnhancements.pdf   

[3] “Coincident Peak measurement frequency scenarios Scenario: 12CP frequency (12 demand measurements, Hybrid TRR split: 50% Volumetric - 50% Peak Demand) Difference between Proposed TAC Charge and Existing TAC Charge ($).” Transmission Access Charge Structure Enhancements Draft Final Proposal, September 2018, pp. 53, Appendix B, https://stakeholdercenter.caiso.com/InitiativeDocuments/DraftFinalProposal-TransmissionAccessChargeStructureEnhancements.pdf

[4] “Section 4: Structure of transmission cost recovery in other ISOs/RTOs.” Review Transmission Access Charge Structure Enhancements Issue Paper, June 2017, pp. 12–18, https://stakeholdercenter.caiso.com/InitiativeDocuments/IssuePaper-ReviewTransmissionAccessChargeStructure.pdf

[5] “Table 2. Summary of ISO/RTO approaches to transmission charges.” Review Transmission Access Charge Structure Enhancements Issue Paper, June 2017, pp. 18, Section 4, https://stakeholdercenter.caiso.com/InitiativeDocuments/IssuePaper-ReviewTransmissionAccessChargeStructure.pdf

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

Comprehensive Alignment of Interconnection and TPD Processes with Order No. 1920 Staggered Planning Cycles and Mitigation of Cyclical Inequities

2. Has this issue previously been submitted? If yes, please provide a reference.

No

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

CAISO’s Order No. 1920 compliance filing establishes a new planning cadence: a Comprehensive Transmission Plan every two years and a Long-Term Regional Transmission Plan every four years. However, the Generator Interconnection Procedures (GIP) and the Transmission Plan Deliverability (TPD) Allocation process have historically functioned on an annual or "snapshot" basis. This misalignment creates three primary structural and equity issues:

• Structural Planning Gaps: Annual Interconnection Cluster Studies may rely on stale transmission base cases during the off-years of the 2-year Comprehensive TPP cycle. Furthermore, there is no current link between the 20-year Long-Term Plan and near-term Cluster requirements, leading to the potential over-studying of upgrades that may eventually be superseded by regional infrastructure.
• Cyclical Inequity in TPD Allocation: Under the new cadence, even-numbered years will produce comprehensive economic, policy, and reliability results, while odd-numbered years (Interim Assessments) will likely focus solely on reliability. This creates a fundamental bias. Projects seeking TPD in even-numbered years will have a significantly higher likelihood of success compared to those seeking it in odd-numbered years.
• Queue Intake Volatility: Because Queue Intake prioritization (via IPE 2023 Track 2) is directly influenced by available and planned transmission capacity, a biennial release of policy-driven capacity will create artificial boom and bust cycles in the cluster windows.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The proposed initiative would conduct a comprehensive audit/review and potential revisions to the GIP (RIS) and TPD allocation rules to ensure they are Order 1920 ready. Key elements include:

• Cycle Synchronization: Aligning the Cluster Study window and cluster studies timelines with the biennial (2-year) Comprehensive TPP to ensure interconnection customers are studied against the most recent, board-approved transmission expansion.
• TPD Allocation Smoothing & Interim Rules: Establishing Interim Year allocation procedures to allow for the release of deliverability that becomes available between planning peaks. This includes a smoothing mechanism to distribute newly approved policy deliverability across a full two-year cycle to prevent calendar-based bias.
• Long-Term Plan Tiering: Developing a new tier of Conditional Deliverability specifically for resources in the 20-year Long-Term Plan corridors, preventing long-lead resources from being penalized by near-term milestone requirements.
• Queue Intake Smoothing: Revising queue intake scoring so that clusters opening in interim years are not penalized for the lack of freshly approved policy transmission, ensuring a steady, predictable pipeline of interconnection requests.    

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

Failure to align these processes may lead to Planning Whiplash, where interconnection customers receive study results that are invalidated 12 months later by a new Long-Term Regional Plan. Correcting this misalignment will:

• Reduce Interconnection Costs: By preventing the study and assignment of redundant network upgrades that are already being addressed by larger-scale 20-year regional projects.
• Improve Commercial Certainty: Ensuring that the deliverability developers see in the TPP is actually available for award in the TPD process without a multi-year lag.
• Maintain Reliability: Ensuring that the Interim Reliability Assessments in off-years are sufficiently robust to authorize immediate-need upgrades without waiting for the full 2-year cycle.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

CAISO’s compliance filing targets 2030 for the first synchronized cycle. However, the policy framework (the "Roadmap") must be established during the Roadmap’s horizon of 2027 to 2029. If this is not addressed in the 2026 Roadmap, CAISO risks entering the 2030 cycle with an interconnection process that is functionally incompatible with its new transmission planning process, possibly resulting in significant stakeholder disputes regarding fairness and deliverability access when the first interim year occurs.

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

• Existing Data: CAISO 20-year Outlook (2022 & 2024), historical TPD allocation success rates, current Cluster Study timelines, and the Queue Intake scoring data from Cluster 16 (leading into the 2027 initiative timeframe).
• Missing Data: A gap analysis of how an off-year Cluster Study (Year 2 of a TPP cycle) would differ in results if it used a draft TPP base case versus a final one, quantitative modeling of TPD availability in reliability-only odd years vs. comprehensive even years, LSE feedback on how biennial TPD allocations will align with annual RA procurement obligations, and a mapping of how many current queue positions fall within the "Long-Term Regional" zones identified in the Dec 2025 filing.  

8. Submission title

N/A

9. Has this issue previously been submitted? If yes, please provide a reference.

N/A

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

N/A

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

N/A

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

N/A

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

N/A

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

N/A

15. Submission title

N/A

16. Has this issue previously been submitted? If yes, please provide a reference.

N/A

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

N/A

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

N/A

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

N/A

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

N/A

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

N/A

1. Submission title

Long Duration Energy Storage (“LDES”) as a Transmission Asset.

2. Has this issue previously been submitted? If yes, please provide a reference.

Yes, CESA (not GreenGen) has previously submitted this issue in 2024 and 2025.

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

CAISO currently lacks a clear and prioritized mechanism to allow long-duration energy storage resources selected in the Transmission Planning Process as reliability solutions to recover costs through the Transmission Access Charge (TAC), even when those resources function operationally as transmission facilities. Long-duration storage, particularly flexible pumped storage hydro facilities, can resolve thermal overloads, manage contingencies, and support voltage in a manner comparable to conventional wires upgrades. While FERC has clarified that storage resources may receive cost-based recovery when providing transmission or grid support services (Docket PL17-2-000, Storage as a Transmission Asset, 2017-01-19), CAISO’s current planning framework does not provide a practical pathway for doing so. This creates a structural bias toward traditional transmission upgrades and limits the ability of planning studies to select cost-effective non-wires alternatives.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The proposed initiative would be limited in scope and focused on establishing a clear pathway for LDES resources to be evaluated, selected, and compensated as transmission assets when identified in the Transmission Planning Process as reliability solutions.

Specifically, GreenGen recommends the initiative address the following elements:

1. Transmission Planning Process (TPP) Framework
   Clarify how LDES may be evaluated alongside traditional wires solutions as a transmission reliability alternative, including criteria for determining when a storage resource functionally qualifies as a transmission facility (e.g., thermal overload mitigation, voltage support, contingency relief).
2. Transmission Access Charge (TAC) Cost Recovery Mechanism
   Develop a defined tariff pathway allowing storage selected through the TPP to recover costs through the TAC when operated to provide transmission services, consistent with FERC policy guidance regarding cost-based recovery for transmission and grid support services ((Docket PL17-2-000, Storage as a Transmission Asset, 2017-01-19).
3. Operational Control and ISO Independence Safeguards
   Establish operational parameters consistent with FERC precedent to ensure CAISO independence is preserved, transmission reliability service receives priority dispatch, and any charging or state-of-charge requirements are structured to avoid double recovery concerns, i.e. both on the charging and discharging side of the LDES resource.
4. Separation of Transmission and Market Functions (Phase II Consideration)
   While concurrent market participation, is an important long-term policy question (as the CAISO explored in its 2018 SATA policy initiative), the scope of this initial initiative should be limited to transmission asset classification and cost recovery. Market participation rules could be addressed in a subsequent phase to allow for stakeholder development of appropriate revenue crediting and competitive safeguards.

Importantly, this initiative avoids modifying core energy market design, resource adequacy accreditation rules, or congestion revenue allocation mechanisms. Rather, it would clarify how long-duration storage resources that are selected to meet defined transmission reliability needs may be treated comparably to other transmission assets under existing planning and cost-recovery structures.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

Prioritizing a new policy initiative to enable a transmission-asset pathway for long-duration energy storage should have positive impacts on both infrastructure development and long-term system reliability.

Providing a clear TAC-based cost recovery pathway for LDES selected through the Transmission Planning Process would materially reduce development uncertainty and financing risk for developers. Long-duration storage projects are capital-intensive and long lead-time resources. Without a defined cost-of-service pathway when selected to meet transmission reliability needs, these projects face greater commercial risk relative to conventional wires upgrades.

Establishing a transmission classification pathway would expand the set of viable non-wires alternatives in TPP studies, allowing CAISO to select the most cost-effective reliability solution rather than defaulting to traditional transmission infrastructure.

LDES resources are uniquely capable of addressing not only peak-hour overloads but multi-hour and multi-day stress events. As net load volatility increases and renewable penetration rises, reliability challenges are becoming more temporal and less purely locational. Long-duration storage can provide sustained discharge during extended peak events, manage post-contingency overloads, and support voltage in ways that 4-hour storage or static wires upgrades may not fully address. A transmission-asset pathway would allow CAISO planning models to capture these operational reliability benefits more explicitly.

Finally, traditional transmission upgrades are long-lived and capital-intensive. In some cases, projected reliability needs may be seasonal, weather-driven, or evolve as load and generation patterns change. LDES can provide a flexible, dispatchable reliability solution that may defer or partially replace certain upgrades while preserving optionality as system conditions evolve.

This flexibility may reduce the risk of overbuilding infrastructure that becomes underutilized as load shapes and resource portfolios change.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

There is no statutory deadline that GreenGen is aware of requiring immediate implementation of a Storage as a Transmission Asset (SATA) framework. However, there are meaningful time-sensitive infrastructure and reliability considerations that support prioritizing this initiative.

Long-duration energy storage resources such as pumped storage hydro and other larger, long-lead time resources require multi-year development timelines, including permitting, interconnection, financing, and construction. Regulatory uncertainty regarding whether an LDES resource selected in the Transmission Planning Process can recover costs through the Transmission Access Charge materially increases financing risk. Absent policy clarity, projects intended to support post-2030 reliability needs may be delayed or fail to advance.

Because transmission upgrades approved through the TPP are long-lived and capital-intensive, failure to clarify the SATA framework before major infrastructure decisions are made may narrow future flexibility. Addressing this issue proactively preserves optionality and allows CAISO to evaluate non-wires alternatives on an equal footing before committing ratepayer funds on irreversible transmission investments.

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

CAISO already possesses most of the data needed to evaluate Storage as a Transmission Asset framework for long-duration energy storage resources. The Transmission Planning Process models thermal overloads, contingencies, voltage support needs, and congestion patterns, while operational and interconnection studies simulate storage dispatch, duration limits, and state-of-charge constraints. These datasets provide a foundation for assessing when LDES could functionally mitigate defined transmission reliability needs.

The primary gap is not new system data, but analytical refinements. These include comparative modeling of LDES as a non-wires alternative within specific TPP reliability cases, evaluation of duration requirements for sustained overload mitigation, development of operational protocols to ensure transmission-service priority, and assessment of TAC cost-allocation impacts relative to conventional upgrades.

In short, the necessary reliability and planning data largely exist; what is needed is a structured framework to evaluate storage as a transmission alternative within CAISO’s existing planning studies.

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

Pacific Gas and Electric Company (PG&E) appreciates the opportunity to provide comments on the California Independent System Operator’s (CAISO) January 27, 2026, presentation regarding the 2026 Infrastructure Policy Catalog and Roadmap Process.

As PG&E previously stated in its February 25, 2026, comments on the CAISO’s Large Load Considerations Issue Paper, PG&E urges the CAISO to start an initiative and move forward expeditiously with the development of new service offerings tailored to large, transmission-connected loads and recommends that this effort be a priority for the CAISO in 2026. Timely and predictable processes for serving large loads will be critical to supporting California’s economic and policy objectives.

Also, with respect to transmission planning, PG&E notes that the CAISO will most likely be entering the implementation phase in 2026 of the Federal Energy Regulatory Commission’s (FERC) Order No. 1920 reforms. PG&E anticipates that 2026 will involve significant stakeholder engagement and procedural development once FERC approves the CAISO’s Order No. 1920 compliance filing. Given the scope and importance of these reforms, PG&E recommends that the CAISO establish and maintain a robust, transparent process for diligence and stakeholder review of any necessary changes to the Transmission Planning Process (TPP) Business Practice Manual.

Taken together, these efforts represent a substantial and important body of work for 2026. PG&E therefore recommends that the CAISO refrain from adding new initiatives for 2026 to an already full agenda. Instead, PG&E encourages the CAISO to focus on refining and improving its existing processes, particularly to support the timely interconnection of large loads and to ensure a comprehensive approach to TPP BPM changes necessary to comply with FERC’s Order No. 1920.

In addition, the CAISO is concluding its Interconnection Process Enhancements 5.0 initiative, which follows several years of significant reforms to the generator interconnection process. PG&E suggests that the CAISO allow sufficient time to assess how these existing reforms affect the Cluster 16 intake and study process before considering whether additional interconnection reforms are warranted.

2. Has this issue previously been submitted? If yes, please provide a reference.

N/A

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

N/A

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

N/A

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

N/A

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

N/A

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

N/A

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

Reliability Modernization Initiative: Align Resource Adequacy Program with Evolving Grid Needs

2. Has this issue previously been submitted? If yes, please provide a reference.

Similar concepts have been raised across CAISO forums (deliverability methodology updates, off-peak deliverability, RA modeling/Slice-of-Day), but not as a single, outcome-oriented proposal to recognize the reliability needs of the modern grid, and the ability of deliverable resources, energy storage, and energy-only resources to contribute. This submission seeks to consolidate and advance those discussions into a concrete initiative that can be scoped and scheduled in the CAISO Catalog.

Key touchpoints include:

• CAISO Deliverability Assessment Methodology refinements (HSN/SSN, dispatch, DFAX), which remain predominantly summer-centric for RA accreditation. [Ref: CAISO, Final Proposal – Generation Deliverability Methodology Review, Jan. 4, 2024]
• CAISO Off-Peak Deliverability Assessment Methodology identifying curtailment risk but not tied to RA accreditation or winter reliability. [Ref: CAISO, Off-Peak Deliverability Assessment Methodology]
• CPUC Slice-of-Day (SOD) RA framework (hourly checks; charging sufficiency) necessitating alignment between RA and deliverability year-round. [Ref: CPUC 2025 RA & Slice-of-Day Guide; CAISO SOD White Paper (Jan 2024)]

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

CAISO’s deliverability and RA constructs continue to center on high-system-need summer hours. That paradigm undervalues energy-only (EO) resources that measurably reduce net load or enable dependable battery charging, and it does not adequately reflect reliability needs in non-summer months as California transitions toward a winter peak. Under the CPUC’s Slice-of-Day (SOD) framework, LSEs must demonstrate capacity sufficiency in all hours and must show charging sufficiency for storage. Without complementary updates on the CAISO side, EO resources that provide charging energy or support winter and shoulder-season reliability are not appropriately recognized, creating misaligned signals and under-utilized grid capability.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

This initiative would:

• Establish an accreditation bridge between CPUC Slice-of-Day and CAISO deliverability/RA so resources can earn reliability value in hours and seasons where they demonstrably contribute (including winter).
• Convert off-peak curtailment findings into actionable reliability improvements by identifying targeted transmission solutions to relieve off-peak constraints and defining how such mitigations translate into deliverability upgrades or RA recognition.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

• Improves year-round adequacy (including winter) by recognizing contributions of EO resource-diverse portfolios.
• Accelerates near-term reliability by recognizing reliability value for the many energy-only projects in the queue, making them contractable by LSEs
• Strengthens investment signals for wind, geothermal, offshore wind, and EO + storage that complement solar and evening peaks.
• Aligns RA obligations under SOD with CAISO deliverability outcomes, reducing reliability gaps and unnecessary costs.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

SOD is in effect for 2025 RA compliance and will shape procurement through 2026–2027. Winter risks are increasing as portfolios diversify and load shapes evolve. Initiating this work now before QC16/TPD cycles and forthcoming procurement lock-ins will avoid another tranche of summer-centric outcomes. If not addressed, California will continue to under-recognize resources that can contribute to charging sufficiency and solve winter and shoulder-season needs, miss cost-effective EO + storage opportunities, and over-rely on expensive alternatives.

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

Existing data:

• CAISO deliverability methodology datasets (dispatch assumptions, monitored elements, DFAX, contingency results).
• Off-Peak Deliverability methodology results identifying curtailment hotspots and mitigation sequences.
• CPUC SOD guidance and CAISO RA/SOD interface materials detailing checks and charging sufficiency.

Missing/needed:

• Accreditation mapping between SOD hours and deliverability outcomes (including a winter module).
• Location-specific curtailment-to-capacity conversion factors to quantify RA gained from targeted transmission upgrades or GETs.

8. Submission title

Robust and Adaptability Testing in CAISO Transmission Planning

9. Has this issue previously been submitted? If yes, please provide a reference.

Elements of robust and adaptability testing appear in CAISO’s annual Transmission Planning Process (TPP) and in CPUC base/sensitivity portfolios, but CAISO does not yet have a formal, standardized framework embedded in TPP for evaluating opportunities to improve the robustness and adaptability of transmission upgrades. This submission proposes creating that formal DMUU element. 

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

California faces elevated uncertainty: rapid load growth from electrification and data centers, evolving resource mixes (offshore wind, long-lead out-of-state wind), extreme weather, and supply-chain/timing risks. Current practice studies a CPUC base case and limited sensitivities, but lacks a standardized stress-testing and robust planning lens that quantifies risk and supports “right-sizing” transmission across plausible futures. A formal module is needed so CAISO’s TPP can proactively identify robust and adaptable transmission solutions that perform well across uncertainty, reduce regret, and improve readiness for policy transmission beyond the CPUC base portfolio.  This approach to transmission planning has been demonstrated by the Midcontinent Independent System Operator (MISO), which included robust testing in development of its 2024 MISO Transmission Expansion Plan (MTEP). 

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The initiative introduces a formal module into CAISO’s TPP, aligned with the planning principles specified in FERC Orders 1920 and 1920-A. The module would apply standardized stress tests annually to CPUC portfolios, examining conditions such as accelerated load growth from electrification and data centers, delays in offshore wind development, constrained availability of out-of-state resources, extreme-weather conditions, and potential delays in interconnection-driven upgrades. CAISO would publish these stress-test results alongside reliability, policy, and economic studies and identify transmission upgrades that are cost-effective at meeting needs across a range of uncertain futures . 

The initiative also establishes a consistent protocol for evaluating right-sizing opportunities and for assessing whether larger-scale, scalable, or staged transmission solutions, including the use of grid-enhancing technologies, provide improved long-term value across scenarios. A policy-proactive track would assess scenario variants beyond the CPUC base portfolio, enabling earlier visibility into policy-driven transmission needs. CAISO would further develop structured menus of transmission and non-transmission options with clear comparative metrics and incorporate robust decision-making criteria that account for downside risk, regret, and option value. 

All findings and methodologies would be documented in an annual Technical Appendix. The initiative also proposes a policy-transmission readiness list and corresponding map to identify projects that are not selected in the base-case plan but that demonstrate robustness across stress tests. Activities would be synchronized with the TPP schedule so that stress-test outputs directly inform project selection. 

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

Implementing robust and adaptability testing is expected to significantly enhance system reliability and resilience by identifying vulnerabilities associated with uncertain load growth, offshore or out-of-state development delays, and extreme-weather events. Earlier detection of robust or scalable transmission solutions will reduce the likelihood of curtailment, reliability risks, or the need for reactive upgrades later in the decade. The framework will also support more cost-effective planning by identifying opportunities where larger or staged projects reduce long-term system costs or avoid repeated rebuilds. Improved alignment between interconnection-related network upgrades and long-term planning will enhance queue efficiency, reduce delays, and accelerate deliverability for high-value resources. 

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

Implement robust and adaptability testing beginning with the current TPP cycle to align with FERC Order 1920/1920-A long-term, scenario-based planning expectations and to address near-term uncertainty from rapid electrification, data-center load, and potential OOS/offshore timing risks. Acting now reduces the chance of under-sizing transmission, stranded upgrades, or RA shortfalls later in the decade. 

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

Existing: CAISO study plans and results; CPUC base/sensitivity portfolios and busbar mapping; interconnection upgrade data; benefit metrics required under federal planning rules; public research on probabilistic/robust planning methods. 

Needed additions: (1) a standardized stress-test library applied each cycle; (2) a robust-planning evaluation sheet (benefits/regrets across scenarios) published with the Draft Plan; and (3) a policy-Tx readiness list and map so robust projects have a visible on-ramp even when not selected in the base case. 

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

 Transmission Access Charge (TAC) Structure Enhancements

2. Has this issue previously been submitted? If yes, please provide a reference.

Yes. Most recently, this issue was submitted by CDWR in 2025 in the CAISO Policy Initiatives Process. It was also included in the CAISO Policy Catalog from 2020-2025. 

This initiative was first explored by the CAISO from 2015-2018 but was put on hold to pursue other initiatives. 

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

The current TAC structure relies solely on volumetric measurements, which fails to capture how the transmission system functions. By incorporating coincident peak-demand alongside volumetric data, a hybrid framework would more accurately reflect the need to deliver energy, ensure greater utilization of transmission capacity and reliability of the grid. This approach would also align cost allocation with the benefits each user receives.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The CAISO previously determined that the existing volumetric-only TAC structure may no longer accurately reflect transmission cost causation or system utilization, citing significant shifts in California's resource mix, load patterns, and overall grid operations. This conclusion prompted CAISO to reexamine both how transmission usage is measured and how transmission costs are allocated among market participants.

The proposed initiative would evaluate whether the current volumetric-only TAC structure continues to accurately capture transmission cost causation and customer benefits. To that end, CAISO could explore alternative billing approaches — including demand-based, time-differentiated, volumetric, and hybrid structures — to determine whether a more reflective cost allocation methodology is warranted.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

This initiative would likely improve system reliability by enabling CAISO to develop additional market signals that incentivize load shifting away from peak periods. It would also drive greater utilization of the existing transmission network, potentially reducing the need for costly future transmission buildout.

As generation and consumption patterns continue to evolve, a hybrid TAC structure would provide the flexibility needed to adapt cost allocation methodologies accordingly — ensuring that both customers and grid reliability benefit as market conditions change.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

There are no regulatory requirements for implementing this initiative, however, CAISO remains an outlier among major ISOs and RTOs in its continued reliance on a volumetric-only transmission access charge methodology. This approach is increasingly at odds with industry norms and fails to create meaningful price signals that would incentivize large energy users to shift load away from peak demand periods. Furthermore, the current structure results in an inequitable cross-subsidization, whereby entities with flexible loads effectively bear a disproportionate share of transmission costs on behalf of those that are unable or unwilling to manage their peak demand exposure.

With the pending creation of a west-wide market, we believe having an equitable structure in place now ensures costs are fairly allocated in the future. 

Additionally, Senator Becker has introduced SB 943, which would urge the CAISO to adopt recommendations from the California Public Utilities Commission regarding TAC reforms that would better align with cost causation principles. 

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

Much of the data was first analyzed in the 2016-2018 initiative would need to be updated. Data to be analyzed could include but not be limited to analysis of 12-month coincident peak, growth of distributed energy resources, growing electrification, changes in customer class composition, analysis of constrained hours, TAC rates, gross load, grid composition, congested transmission lines, and incorporation of CAISO's recently adopted transmission plans. 

CAISO could also analyze how different hybrid structures and implementation timeframes would impact existing customers.

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

1. Submission title

Maximum Import Capability (MIC) Enhancements   

2. Has this issue previously been submitted? If yes, please provide a reference.

Yes, the California Community Choice Association, Shell Energy North America (US), L.P., and the Six Cities (Cities of Anaheim, Azusa, Banning, Colton, Pasadena, and Riverside, California) submitted this issue into the 2024 stakeholder catalog.[1] As a result, the CAISO scoped this issue into the Resource Adequacy (RA) Modeling and Program Design (RAMPD) initiative,[2] but has yet to address it.  

[1]           https://stakeholdercenter.caiso.com/Comments/AllComments/7229828e-d159-4450-b317-4026172a6b55#org-06ad7cfb-56c8-4d6a-a396-a13aa8e57de0.

[2]           https://stakeholdercenter.caiso.com/InitiativeDocuments/Appendix-B-2024-Final-Dispositions.xlsx.

3. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

California Public Utilities Commission (CPUC)-jurisdictional and non-CPUC-jurisdictional load serving entities (LSE) are facing challenges in contracting out-of-state (OOS) resources due to the lack of available MIC and uncertainty around the availability of MIC in the future. The CAISO should address these challenges urgently given the significant role OOS resources are anticipated to play in meeting reliability and clean energy needs.

The CPUC’s recently adopted Preferred System Plan (PSP) includes 19 gigawatts (GW) of new OOS wind by 2045.[1]^{, [2]} These OOS resources will require MIC to count towards LSEs’ Resource Adequacy (RA) and Integrated Resource Plan (IRP) obligations. Non-CPUC jurisdictional utilities may also be developing resource portfolios that include imported RA resources. Uncertainty regarding whether MIC will be available to support these projects is a significant barrier to LSEs moving forward with Power Purchase Agreements (PPA) for OOS projects. Enhancements in the efficiency of MIC allocations and increasing the availability of MIC should help make import capacity more available to enable meeting RA and IRP requirements. 

The Joint Parties have identified several problem statements regarding the MIC calculation and allocation processes that should be addressed in this initiative. These problem statements include, but should not be limited to, the following:

• The long-term MIC process is not conducive to PPAs with future commercial operation dates beyond the immediate year;   
• There may be insufficient MIC to meet LSE demand on popular interties; and
• Available MIC may go unused because of either: (1) a cumbersome trading mechanism; (2) parties not making their unused allocations available for trade, and/or (3) parties making unused MIC available at unusable locations.

Other potential questions to explore include: (1) how to balance limited internal and external deliverability; (2) how well does a methodology based on historical import levels support future needs and capabilities; and (3) how should a potential multi-year need be addressed (e.g. multi-year RA)?  

[1]             Proposed Decision Requiring 2029-2032 Electric Resource Procurement And Transmitting Portfolios For 2026-2027 Transmission Planning Process, R.25-06-019 (Feb. 26, 2026) at 56: https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M600/K854/600854771.pdf.

[2]           The CAISO’s 2026-2027 Transmission Planning Process (TPP) Base portfolio includes 17 gigawatts (GW) of new OOS wind by 2041 as reported in the CAISO DRAFT Study Plan 2026-2027 Transmission Planning Process (Feb. 17, 2026) at 45: https://stakeholdercenter.caiso.com/InitiativeDocuments/2026-2027-Transmission-Planning-Process-Unified-Planning-and-study-Plan-Draft-Feb-2026.pdf.

4. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

The Joint Parties recommend exploring enhancements to the MIC calculation and allocation methodology to address the problem statements in section 3 above, and any additional, related problem statements that may arise through stakeholder working group discussions. These enhancements should recognize that MIC is fundamentally a transmission deliverability and interface capability issue that affects all CAISO market participants, regardless of regulatory jurisdiction. The CAISO should continue to scope this initiative into the RAMPD initiative, given the many policy implications MIC enhancements initiative has with respect to the RA program.

While the Joint Parties recommend this initiative remain within the scope of the RAMPD initiative, we are submitting this initiative in both the market design policy catalog and the infrastructure policy catalog. The bulk of the issues in this proposal are squarely market design issues in the RA program.  However, there may be a subset of issues, such as calculation methodology changes, that fit best within an infrastructure-driven initiative. If so, these issues could be bifurcated as the stakeholder process develops.

5. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

The CPUC has recently identified a 6,000 MW[1] reliability need between 2029-2032 and has ordered CPUC-jurisdictional LSEs to procure new resources to meet this reliability need.[2] In addition to CPUC-identified reliability timelines, non-CPUC-jurisdictional LSEs face immediate contracting timelines that require greater certainty around future MIC availability several years in advance of commercial operation dates. California has historically depended on contracted import capacity to maintain reliability.[3] This trend is likely to continue in the coming years, as demonstrated by the CPUC’s recently adopted PSP, described above. Uncertainty regarding whether MIC will be available to support these projects is a barrier to the development of OOS projects that could be needed to support system reliability in the near and long term.  Enhancements in the efficiency of MIC allocations and increasing the availability of MIC should help make import capacity more available to meet these reliability needs. 

[1]           The need is denominated in Net Qualifying Capacity and since the resources are likely to come from non-emitting resources, the amount of installed capacity will be significantly greater. 

[2]              Id., at 2.

[3]           Analysis in the Joint Parties prior catalog submission shows that LSEs are dependent on imports to meet RA requirements, and from 2020-2023, CAISO interconnected resources alone were insufficient to meet RA requirements in total: https://stakeholdercenter.caiso.com/Comments/AllComments/7229828e-d159-4450-b317-4026172a6b55#org-06ad7cfb-56c8-4d6a-a396-a13aa8e57de0.

6. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

This issue should be addressed immediately, as it is one of the most urgent issues scoped into the RAMPD initiative. As discussed above, the CPUC has found a reliability need in 2029-2032.[1] The ability to obtain the MIC necessary to support imports could make the difference between having enough RA-eligible supply to meet reliability targets and coming up short.

LSEs are contracting to meet IRP requirements, including the recently proposed CPUC procurement order,[2] their own IRPs which will be updated this year,[3] and the CPUC’s PSP, which includes 19 GW of OOS wind by 2045.[4] Non-CPUC jurisdictional LSEs are likewise actively engaged in planning and procurement to meet long-term needs. Some OOS projects are currently in the process of contracting to provide capacity to California,[5] but the lack of available MIC is hampering those efforts. In addition, transmission projects are under development using Subscriber Participating Transmission Owner (SPTO) Model and a review of MIC policy is necessary to ensure MIC availability is aligned with the in-service date of SPTO projects. The CAISO should urgently begin a MIC Enhancements initiative to ensure reliable delivery of supply now and in the future.  

[1]             Proposed Decision Requiring 2029-2032 Electric Resource Procurement And Transmitting Portfolios For 2026-2027 Transmission Planning Process, R.25-06-019 (Feb. 26, 2026) at 2: https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M600/K854/600854771.pdf.

[2]           Ibid.

[3]           Administrative Law Judge’s Ruling Setting Requirements For Individual Integrated Resource Plans Due June 1, 2026, R.25-06-019 (Jan. 16, 2026): https://docs.cpuc.ca.gov/PublishedDocs/Efile/G000/M595/K085/595085015.PDF.

[4]             Proposed Decision Requiring 2029-2032 Electric Resource Procurement And Transmitting Portfolios For 2026-2027 Transmission Planning Process, R.25-06-019 (Feb. 26, 2026) at 56: https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M600/K854/600854771.pdf.

[5]           Cumulative New Resources included in Non-CPUC Jurisdictional IRP Plan, as reported in CAISO 2026-2027 Transmission Planning Process –Draft Transmission Plan Stakeholder Meeting, February 24, 2026 at 71: https://stakeholdercenter.caiso.com/InitiativeDocuments/Presentation-2026-2027-Transmission-Planning-Process-Feb-24-2026.pdf.

7. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

The CAISO has the data needed to analyze this issue. OASIS includes monthly MIC rights allocated by intertie and LSE, monthly MIC used in RA showings by intertie and LSE, monthly MIC made available to trade by intertie, and monthly MIC traded by intertie. This information can be used to investigate the severity of the following two main sources of MIC availability challenges: (1) insufficient MIC to meet LSE demand on popular interties; and (2) unused MIC either because of a cumbersome trading mechanism, MIC not being made available, or unusable location. Analysis of this data should be used to prioritize solutions that can address the most pressing issues.

8. Submission title

9. Has this issue previously been submitted? If yes, please provide a reference.

10. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

11. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

12. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

13. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

14. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.

15. Submission title

16. Has this issue previously been submitted? If yes, please provide a reference.

17. Issue Description: Briefly provide a description of the infrastructure policy issue that the proposed initiative is intended to address.

18. Proposed Initiative Description: Discuss the scope of the proposed initiative. What specific elements of existing ISO infrastructure policy does your initiative propose to address?

19. Impact: To the extent possible, discuss any anticipated impacts to infrastructure development or system reliability.

20. Timing and Urgency: Are there regulatory requirements for implementation dates, or time-sensitive reliability impacts? Are there consequences to not addressing this issue?

21. Data: Identify existing data and missing data needed to analyze the issue and develop solutions.