Comments on 8/13 & 8/14 meeting and straw proposal

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

Comments on Gas Resource Management:

Straw Proposal

Department of Market Monitoring

August 26, 2025

Summary

The Department of Market Monitoring (DMM) appreciates the opportunity to comment on the Gas Resource Management Straw Proposal.[1] The purpose of the proposal is to advance the stakeholder recommendations from the Gas Resource Management working group, which aims to improve the functionality for regional market participants with natural gas-fired resources in the CAISO market, including in the Western Energy Imbalance Market (WEIM) and the Extended Day-Ahead Market (EDAM). DMM provides comments here on the following topics discussed in the straw proposal and the ISO’s latest presentation:

• Informing fuel procurement. DMM supports the ISO’s efforts to provide scheduling coordinators with accurate advisory gas burn schedules. DMM believes the ISO should provide analysis of the appropriateness of using various alternative bid sets to fill in bids for resources that do not submit in time for the two-day advisory (D+2) market run.
• Accommodating cost variation. DMM supports the general direction of the ISO’s proposals to allow more accurate reflection of gas costs in market bids. However, the straw proposal is missing many details necessary to fully evaluate the proposal’s appropriateness and effectiveness. DMM believes the ISO should provide stakeholders with more information about how forecast uncertainty could affect the reasonableness threshold, including how much forecast uncertainty will trigger the reasonableness threshold increase, and how much the reasonableness threshold will be increased. DMM also believes the ISO should provide more details and analysis of the default fuel multiplier, including how this value will be established, and the range of potential values.
• Negotiated commitment costs and blended fuel regions. The straw proposal also contemplates development of negotiated commitment costs and a blended fuel region methodology. DMM supports the ISO and stakeholders continuing discussions to clarify details of these proposals. In general, DMM supports automated processes where possible to reflect resource costs in the market. 
• Managing gas burn limitations. DMM continues to recommend not including operation flow order (OFO) costs in reference level calculations.

Comments

DMM supports the ISO’s efforts to provide scheduling coordinators with advisory gas burn schedules and prices using the D+2 report through CMRI. However, additional analysis is needed to determine the appropriate bid set to use when calculating the D+2 advisory schedules.

The ISO is proposing to replace the residual unit commitment (RUC) advisory schedules from the 48-hour RUC look-ahead process with advisory reliability capacity schedules from the D+2 and D+3 advisory runs. The inputs and assumptions of the D+2 are potential improvements over the 48-hour RUC look-ahead. Where the 48-hour RUC look-ahead and current D+2 report use bids from 7 days prior to the relevant trade date, the ISO recognizes the opportunity to use more recently submitted bids to increase the accuracy of advisory schedules and decrease gas burn uncertainty heading into real-time.

The ISO is seeking feedback on what to do when bids are not submitted in time for the D+2 market run. The straw proposal suggests using the day-ahead bid set submitted for the day-ahead market on the day the D+2 is run (day-ahead bids), bids from 7 days prior, or using either of those options at the discretion of operators as inputs to the D+2 market run.

DMM appreciates the thorough discussion in the paper to explain the pros and cons of using day-ahead bid sets versus using bids from 7 days prior, particularly about mixing weekend bids for weekday forecasts. DMM believes the ISO should analyze historical data to determine if using day-ahead bids or 7 day prior bids result in more accurate gas burn forecasts on average, and if there are specific situations where one set of bids outperforms the other (e.g., when weather conditions are drastically different than the previous week, or when using weekend bids would cause issues for early weekday forecasts).

One stakeholder suggestion during the straw proposal presentation on August 12 was to require resources to submit bids in time for the D+2 market run, to increase the accuracy of the advisory schedules and reliability. It was also suggested that the ISO consider multi-day settlement to help incentivize accurate bidding in this scenario. It is unclear how much traction this suggestion may garner, considering the amount of work the ISO would need to implement multi-day settlement. However, DMM believes this may introduce unintended complications for forward contracts, congestion rent, and CRRs just for the benefit of more accurate advisory schedules.

The ISO should provide stakeholders with more details on the proposal for forecast uncertainty to affect the reasonableness threshold

The ISO proposes to increase the reasonableness threshold in response to high forecast uncertainty observed between the D+2 and day-ahead market runs. Like the day-ahead, the ISO will use the most recent demand forecasts for the D+2 market run to produce a D+2 net load forecast and uncertainty requirement for each EDAM balancing area.

DMM appreciates that one of the primary concerns stakeholders had in the working group was to minimize the uncertainty around fuel procurement targets to avoid exposure to intra-day gas prices. DMM understands that the proposal to adjust the reasonableness threshold in response to higher forecast uncertainty is intended as one way to address this concern. However, to assess the effectiveness and appropriateness of this proposal, DMM believes the ISO should provide more information on the proposal. DMM suggests the ISO:

1. Conduct analysis to determine what specific level of forecast uncertainty is an appropriate trigger to increase the reasonableness threshold:
   1. Is the threshold a static number between the D+2 and day-ahead markets?
   2. Is it a dynamic trigger that depends on other factors?
   3. Is the uncertainty level trigger balancing area specific?
   4. Does the ISO have any discretion to determine when the reasonableness threshold is increased or not?
2. Define the level of reasonableness threshold increase:
   1. Will the reasonableness threshold increase be a static number?
   2. Will it be a dynamic value that depends on the value of observed forecast uncertainty?
3. Once the uncertainty level trigger is defined, provide a historic analysis that shows how often, when, and where the reasonableness threshold would have been raised:
   1. Are there any similarities between the days where this occurs that may shed more light on what types of days, seasons, or events cause this uncertainty beyond the “exceptional circumstances” the ISO analyzed in the paper?
   2. Is there a clear link between increased forecast uncertainty and higher inter-day gas price volatility to suggest that a higher reasonableness threshold may be appropriate in all instances of elevated forecast uncertainty?

Commitment costs and default energy bids should reflect resource costs without being unnecessarily high to allow exercise of market power or result in inefficient market prices. More information is needed to consider if the proposed reasonableness threshold increase in response to demand forecast uncertainty increases or decreases market efficiency.

DMM supports the ISO continuing to evaluate the accuracy of the D+2 and D+3 market runs after EDAM go-live to verify the value market participants get in the advisory gas burn schedules, and to determine if any changes need to be made. DMM also supports the ISO focusing on analyzing the benefits of the D+2 before considering a D+1.5.

The ISO should provide more details and analysis of the default fuel multiplier used in reference level calculations during persistent conditions

Stakeholders are more concerned with the determination of the fuel cost component of reference levels than the default multipliers, and are concerned that the current reference level change request (RLCR) process is not flexible enough to accommodate resources managing multiple fuel hubs or facing gas supply constraints. The ISO is proposing to apply a configurable default fuel (GPI) multiplier to the fuel region level, so that both default costs and the reasonableness threshold are affected, and more costs can be covered through the automated process.

DMM agrees with the ISO’s assertion in Appendix A of the issue paper that increasing the reasonableness threshold can accommodate a larger volume of gas costs, but also reduce market power protection and inflate costs. The tradeoff between increased bidding flexibility from an automated cost recovery mechanism and reduced market power is not straightforward to predict or evaluate.[2] This is why it is important for proposed increases to reference levels—even those that are expansions of existing market instruments, such as the adjustments for persistent conditions discussed in the BPM for Market Instruments—to be clearly discussed and analyzed before implemented.

In the existing policy, if the ISO observes through after-market cost recovery that a resource’s costs are systematically greater than the GPI used in reference level calculations, then the ISO can apply a resource-level multiplier to the reasonableness threshold for a determined period. In the current initiative, the ISO is proposing to also apply the resource-specific gas price multiplier to the default commitment costs, as well as allowing resource entities to proactively request that the ISO evaluate their costs to determine if a resource scalar is appropriate.

DMM understands that the ISO is seeking feedback from stakeholders on the specifics of how to assess and implement the resource scalar. These include how far back the ISO should look to assess if a multiplier is appropriate, how long the multiplier should be active for, how often the resource entity can request an ISO evaluation, and what level of observed volatility stakeholders would want covered. DMM encourages the ISO and stakeholders to continue discussing these details, and DMM believes the ISO should:

1. Provide details on how the resource-specific multiplier would be calculated.
   1. Is there a formula to calculate the multiplier?
   2. Is there a cap on the multiplier?
   3. What period of time would be analyzed when determining if a resource-specific multiplier is needed?
2. Provide analytical examples of the impact of different options (e.g., multiplier levels, observed volatility to be covered, etc.) using historical or example data.

DMM supports automated processes to reflect resource costs where possible

In addition to the resource-specific gas multiplier discussed above, the straw proposal also contemplates development of negotiated commitment costs and a blended fuel region methodology. For the negotiated commitment costs, the ISO seeks input on deciding between a new negotiated commitment cost option that is separate from the negotiated default energy bid (DEB) process, and a negotiated resource-specific fuel cost parameter to inform commitment cost and other reference levels. For the blended fuel region methodology, the ISO seeks input on what an appropriate methodology is for determining GPI values, what time period the methodology should apply for, how many hubs can be included in the blended fuel region, and how the ISO should collect and validate volumetric gas information.

DMM supports the ISO and stakeholders continuing discussions to clarify details of these proposals. In general, DMM supports automated processes where possible to reflect resource costs in the market.  If a negotiated rate is necessary to accurately reflect cost, DMM notes that in order to minimize needed negotiations, a negotiated fuel component that could serve both commitment costs and DEBs may be preferred over a separate commitment cost negotiation process. Should the ISO and stakeholders determine that any new negotiation of fuel costs or commitment costs would be necessary, DMM notes that the ISO would be the appropriate owner of such a process, rather than DMM.

Operational flow order (OFO) penalties should not be included in reference level calculations

Stakeholders are concerned that OFO conditions can cause gas resources to incur costs that may exceed what their reference levels reflect. As noted in the straw proposal, this can occur when a resource takes actions to avoid violating an OFO (e.g., purchasing gas under tight conditions at prices that exceed index prices), or when bid mitigation results in incremental dispatch that forces a resource to violate an OFO and incur a gas pipeline penalty. Therefore, some stakeholders want to capture OFO conditions in reference levels.

DMM continues to recommend not including OFO costs in reference level calculations. If participants can recover costs that signal gas system constraints through reference levels in the electric market, their demand for gas may not be as sensitive to these price signals. This loss of price sensitivity can negate the purpose of gas pipeline penalties and potentially contribute to gas system reliability issues.

DMM agrees with the ISO that market participants have access to existing tools for gas resources to manage intra-day nomination revisions, price volatility, and different sources of fuel in response to large price spreads and gas market illiquidity that may result during OFO periods. DMM also notes that outage cards, when used in accordance with the CAISO Tariff, are an effective tool to limit resource dispatch during periods of fuel unavailability. DMM encourages the ISO and stakeholders to continue discussions to identify any specific conditions that would force resources to violate an OFO that cannot be addressed by existing tools.

Finally, the ISO proposes to standardize the process for balancing areas to request access to the ISO’s gas nomogram constraint for use under the set of conditions pre-defined by FERC. As noted in the straw proposal, the gas nomogram was approved specifically for physical constraints impacting gas and electric system reliability, under a narrow set of conditions. DMM supports continued discussion of this proposal to further improve gas-electric coordination to reduce inefficiencies in electric market outcomes during gas supply limitations.

[1] Gas Resource Management Straw Proposal, California ISO, July 25, 2025: https://stakeholdercenter.caiso.com/InitiativeDocuments/Gas-Resource-Management-Straw-Proposal-Jul-25-2025.pdf

[2] Gas Resource Management: Straw Proposal scoping and alignment, California ISO, April 16, 2025: https://stakeholdercenter.caiso.com/InitiativeDocuments/Presentation%20-%20Gas%20Resource%20Management%20-%20Apr%2016%202025.pdf

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

Please see the PDF attached below the final question for DMM's fully formatted complete set of comments. For the reader's convenience, the complete text of the comments is pasted in response to #1, but there may be some formatting errors.

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

Please see the PDF attached below the final question for DMM's fully formatted complete set of comments. For the reader's convenience, the complete text of the comments is pasted in response to #1, but there may be some formatting errors.

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

Please see the PDF attached below the final question for DMM's fully formatted complete set of comments. For the reader's convenience, the complete text of the comments is pasted in response to #1, but there may be some formatting errors.

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

Please see the PDF attached below the final question for DMM's fully formatted complete set of comments. For the reader's convenience, the complete text of the comments is pasted in response to #1, but there may be some formatting errors.

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

Please see the PDF attached below the final question for DMM's fully formatted complete set of comments. For the reader's convenience, the complete text of the comments is pasted in response to #1, but there may be some formatting errors.

7. Please provide any additional feedback not already captured.

Please see the PDF attached below the final question for DMM's fully formatted complete set of comments. For the reader's convenience, the complete text of the comments is pasted in response to #1, but there may be some formatting errors.

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

While MRP appreciates the CAISO's efforts to improve the D+2 advisory information, MRP remains concerned that merely improving the average performance of this advisory information will be sufficient to provide market participants to transact more in the timely cycle, especially under extreme conditions.  MRP appreciates the CAISO's willingness to consider modifying the reasonableness threshold to account for persistet conditions.  And MRP is open to the CAISO expanding the use of gas nomograms outside Southern California, but believes that it is not possible to assess the reasonableness of doing so based on general principles, without more specifics and details on the potential use.  

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

Given the reality that neither the gas day timing nor the electric day timing are going to change, MRP appreciates the CAISO exploring ways to provide better information to operators of gas-fired generation prior to the gas timely cycle.  A further constraining reality, however, is that non-financially binding information is unlikely to provide sufficient incentive or protection for market participants to fully procure their gas needs in the timely cycle.  While the CAISO notes that “On average, the D+2 forecast is a reasonably accurate forecast of day-ahead binding energy schedules for gas resources”[1], the challenge and exposure for market participants does not come when conditions are not average, but rather when conditions are extraordinary.  To be most useful, market participants must be able to trust advisory information under extreme conditions, so presenting the performance of advisory schedules on average is not especially reassuring. 

[1] July 25 Straw Proposal at page 13.

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

The July 25 Straw Proposal notes (at page 26) many instances where next-day gas indices significantly underestimate same-day gas costs (i.e., by more than 25%).[1]  In that light, MRP is encouraged that the CAISO discuses adjusting the reasonableness threshold for “persistent conditions” to better allow a resource to recover its costs through the automated reference level change process.  The CAISO’s later observation that it has not observed a strong correlation between weather anomalies and exceptional gas supply conditions[2] seems to undermine the CAISO’s willingness to consider and implement changes to reasonableness thresholds, and MRP requests that the CAISO discuss how it intends to reconcile those two conflicting discussions.  

[1] July 25 Straw Proposal at page 26. 

[2] July 25 Straw Proposal at page 32.

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

The CAISO’s discussion of this topic centers on generic concepts to allow the use of gas burn nomograms by other Balancing Authority Area operators.  While this generic discussion seems reasonable, whether the use of gas nomograms outside of Southern California area is reasonable must involve the specifics of how the nomogram will be used and what effects that nomogram will have on market prices.  MRP supports further discussion on this matter and looks forward to the conversation moving beyond general principles to more details and specifics.   

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

Please see the response to topic 4.   

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

Please see the response to topic 4.   

7. Please provide any additional feedback not already captured.

Inasmuch as recent discussions in other stakeholder initiatives (e.g., Storage Design and Modeling) have focused on the applicability of Resource Adequacy Availability Incentive Mechanism (“RAAIM”) penalties (e.g., the CAISO’s insistence that market participants use Nature-of-Work (“NoW”) categories that subject storage resources to RAAIM penalties when market participants submit outage cards to account for those resources’ foldback/non-linearity limitations), MRP again requests that the CAISO bifurcate the “Fuel Insufficiency” NoW so that fuel insufficiency that is due to a Scheduling Coordinator’s failure to secure fuel would remain subject to RAAIM, but fuel insufficiency that is beyond a Scheduling Coordinator’s control (e.g., due to the outage of gas delivery system facilities) is not subject to RAAIM. This outcome would be completely consistent with how the CAISO currently exempts from RAAIM penalties transmission-induced outages beyond the control of the generator owner.[1]  

[1] CAISO BPM for Reliability Requirements at page 121. 

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

NV Energy appreciates CAISO for initiating the Gas Resource Management stakeholder initiative to address persistent challenges within the EIM and to proactively consider gas management concerns in the forthcoming EDAM. While NV Energy has consistently supported the inclusion of a two-day-ahead advisory schedule, we also strongly advocate for enhanced bidding flexibility and the development of a reliability tool as essential components of a comprehensive solution.  At this time, NV Energy does not believe that the straw proposal meets what is needed for a comprehensive solution and provides additional comments for each element of the design.

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

NV Energy appreciates CAISO’s initiative to enhance the D+2 advisory market schedules to better support the Timely gas nomination cycle. Accurate and reliable D+2 results are critical for informed gas procurement decisions, and while we acknowledge that these forecasts will never be perfect, NV Energy strongly supports any improvements that increase their utility and precision.

NV Energy expresses a preference for Option 1, which bases the D+2 advisory run on bids from the Day-Ahead (DA) market. This approach reflects actual market behavior and offers a more realistic foundation for forecasting, thereby improving the relevance of the advisory results for procurement planning. NV Energy is interested in Option 3 presented in the Straw Proposal paper but seeks more information. Specifically, if Option 3 is selected, NV Energy would like to know how CAISO chooses between using the DA bids or bids from 7 days prior. To further strengthen the advisory process, NV Energy suggests the introduction of a D+4 market run to support weekend procurement and planning for Monday gas days. This additional run could provide valuable foresight for market participants navigating multi-day operational windows.

However, NV Energy is concerned with the amount of D+1 bids submitted before the D+2 process is run. NV Energy notes that the data presented in the Straw Proposal draws on bids from resources within CAISO. NV Energy believes that bid submissions could change once EDAM begins. The lack of submitted D+1 bids could significantly affect the accuracy of the D+2 advisory schedules. Therefore, NV Energy recommends CAISO report the usage of D+1 bids and proxy bids used in the D+2 advisory run.

NV Energy recommends that CAISO explore other performance metrics in addition to gas burn to effectively assess the accuracy and usefulness of the D+2 advisory schedules. NV Energy is concerned that using gas burn does not accurately reflect the difference between the D+2 and D+1 results. NV Energy recommends CAISO present additional measurement metrics and detail between the accuracies of the D+2 and D+1 results. CAISO should also provide data by Balancing Authority (“BA”) or, preferably, by pipeline. Evaluating the D+2 results at the aggregate market level does not offer sufficient insight into how well the advisory schedules support individual market participants. Instead, the forecasts should be detailed enough to determine their practical value for procurement decisions. Where feasible, CAISO should monitor and report performance at the market participant level to ensure the advisory schedules are meeting operational needs and contributing meaningfully to gas procurement planning.

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

NV Energy has no specific feedback regarding the proposed reference level changes at this time, as the proposals are currently under internal review. However, we appreciate the opportunity to engage in this process and will continue to evaluate the implications of the proposed changes.

At this stage, NV Energy expresses a preference for a simpler solution to address the need for increased commitment cost caps for market-based bids, rather than pursuing a more complex redesign of the reference level methodology. Slide 67 in the CAISO presentation clearly indicates that the FERC precedent is that market participants are responsible for submitting fuel procurement risks through bidding.¹ We believe that this issue warrants further discussion among stakeholders. To reiterate, NV Energy supports a reevaluation or a discussion of the market-based commitment cost approach that has already been approved by the CAISO Board, with the goal of ensuring that the framework remains effective and responsive to current market conditions.

Additionally, NV Energy seeks clarification on the operational aspects of the proposed reference level changes. Specifically, whether the new process will allow for adjustments to be made across multiple resources and configurations on a single pipeline, or whether market participants will be required to manually update each configuration for each resource individually. Understanding the level of administrative burden and flexibility associated with these changes is critical for assessing their feasibility and impact.

¹ California Independent System Operator. (2025, August 12). Gas resource management straw proposal [Slide 67]. https://www.caiso.com/Documents/Presentation-Gas-Resource-Management-Straw-Proposal-Aug-12-2025.pdf

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

NV Energy supports extending the nomogram functionality to the broader market footprint beyond California. Market participants in the Western U.S. region face their own unique gas constraints other than just California, and it is important that this functionality be available to benefit the entire footprint rather than being limited to a single geographic area. However, while we support the broader application of the nomogram concept, we do not believe the proposed feature will be particularly helpful in addressing the specific operational challenges faced by NV Energy. We encourage CAISO to continue exploring meaningful enhancements that support the needs of a diverse region.

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

No comment

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

No comment

7. Please provide any additional feedback not already captured.

No comment

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

• PG&E supports CAISO’s efforts to improve D+2 forecast accuracy and recommends identifying hours with lower confidence for targeted improvements.
• Clarity on bid set expectations and market run completeness is essential to make D+2 advisory schedules useful for planning.
• PG&E seeks transparency on import/export assumptions, as they impact gas generation needs.
• PG&E endorses strong, auditable guidelines for using gas constraint nomograms to prevent conflicts of interest.

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

• PG&E appreciates CAISO’s continued efforts to enhance forecast accuracy in the Day-Ahead (D+2) market.
• While the overall forecast confidence is reported at 95%, we acknowledge that accuracy may vary during certain hours due to unique market or system conditions. We encourage CAISO to identify these specific instances and their underlying drivers to inform targeted improvements.
• The reliability of the D+2 advisory schedules is substantially dependent on participant understanding of the inputs used in the simulated market processes. PG&E recommends that CAISO clarify its expectations for market participant bid sets —what is required and what is preferred—as well as the forecasts CAISO will use as inputs. Additionally, it would be helpful for CAISO to indicate the completeness of the market runs (e.g., whether they include processes beyond the raw IFM algorithm, and whether transmission modeling will match the fidelity of the Day-Ahead market, etc.). With this transparency, PG&E believes the D+2 advisory results can be a valuable planning tool.
• Gas generation is often dependent on CAISO imports and exports. Regional demand in the northwest and southwest influence the need for CAISO gas generation. PG&E requests clarification on the assumptions CAISO makes regarding imports and exports in the D+2 market.

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

No comment. 

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

No comment. 

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

No comment. 

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

The proposed guidelines appear to offer strong safeguards against strategic or economic misuse of gas constraint nomograms. It is critical that these guidelines—once fully defined—are consistently applied, auditable, and structured to prevent any conflicts of interest between electric and gas entities and market participants.

7. Please provide any additional feedback not already captured.

No comment. 

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

PacifiCorp finds that the Straw Proposal is moving in the right direction. All of the proposals give scheduling coordinators better tools for procuring gas and managing gas resources. PacifiCorp also appreciates that the CAISO is willing to extend a reliability tool, gas nomograms, to Western Energy Imbalance Market (“WEIM”) and Extended Day-Ahead Market (“EDAM”) scheduling coordinators.

PacifiCorp is still strongly in favor of extending the D+2 market run to include more days. The D+2 market will undoubtably be useful for scheduling coordinators, but an extended look-ahead will give scheduling coordinators more information for procuring gas on weekends, Mondays, and even Tuesdays when there is a Monday holiday. PacifiCorp urges the CAISO to provide more information in a future stakeholder meeting on what the roadblocks are for developing a D+X market run.

PacifiCorp found the meeting on gas nomograms very useful. Developing a standardized process for scheduling coordinators and gas companies to develop a gas nomogram with the CAISO will give market participants another reliability tool they can choose to use. It seems likely that gas nomograms will continue to be used infrequently because of the reliability conditions that need to be triggered in order to activate the nomogram. PacifiCorp believes the conditions and eligibility for use should remain so that gas nomograms are only used in reliability situations, as the tool is not meant to manage gas resources for economic or regulatory reasons.

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

PacifiCorp continues to believe the D+2 market run should be expanded to include more days. Specifically, the CAISO should run at least a D+5 advisory market so that scheduling coordinators have more information for procuring gas for Saturday through Tuesday. Today, PacifiCorp procures gas on Fridays for Saturday, Sunday, Monday, and Tuesday morning. If a D+5 market run happened on Thursday, with the advisory gas resource schedules made available to scheduling coordinators by Friday morning, gas traders would have another potentially valuable piece of information for procuring gas for Saturday through Tuesday. PacifiCorp acknowledges that there will likely be a decrease in accuracy as the market run looks further into the future, but PacifiCorp still believes the information will provide value to scheduling coordinators for procuring gas. Furthermore, extending the look-ahead period of the market run will give scheduling coordinators the opportunity to see how advisory schedules are changing as more accurate forecasts are used. For a D+5 market run on Monday, scheduling coordinators would be able to see advisory gas resource schedules for Friday. By the time scheduling coordinators finalize their bids for the day-ahead market on Thursday, which will produce binding results for Friday, they will have three days of advisory gas resource schedules to see how the updated forecasts may change how their gas resources are used by the market. This is useful information for PacifiCorp’s gas and power traders.

PacifiCorp appreciates the CAISO’s analysis on the daily average gas burn accuracy for the D+2 Integrated Forward Market (“IFM”) and Reliability Unit Commitment (“RUC”). The results are generally positive because it shows that the D+2 market runs are reasonably accurate forecasts of the day-ahead market results. In PacifiCorp’s opinion, the results support moving forward with working to improving the inputs for the D+X market runs to improve accuracy. While additional analysis is not necessary to show the value in the D+X market run, PacifiCorp believes it would be useful to see how the D+X advisory gas schedules compared to the real-time dispatch of CAISO gas resources. This will help show scheduling coordinators how well the D+X advisory schedules predicted the amount of gas that was actually used by their gas resources.

PacifiCorp supports the CAISO’s proposal to provide advisory-only reports to scheduling coordinators through the Customer Market Results Interface (CMRI).

For the bid set that should be used in the D+X market runs, PacifiCorp will be submitting resource bids to the CAISO seven days in advance. Therefore, these bids should be used for the PacifiCorp resources in the D+X market run. If for some reason PacifiCorp does not have submitted bids for future days, the Company believes it would be more accurate to use the previous day’s bids rather than using a historical bid from the same day of the previous week. PacifiCorp is not sure this will be the most accurate option for all scheduling coordinators though, and therefore this topic should be discussed further in a future meeting.

On whether the market power mitigation (MPM) framework should be applied to supply offers submitted for the D+X advisory market runs, PacifiCorp supports using scheduling coordinators’ submitted bids if they are available. While the bids will not be screened for market power, PacifiCorp believes the bids would still be more accurate than using a historical bid that was screened for market power because the submitted bids will better reflect current gas costs. PacifiCorp requests that the CAISO discuss in a future meeting whether it would be feasible to include a market power mitigation pass in the D+X market runs, because it would ultimately lead to the most accurate resource bids being used.

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

No comment.

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

PacifiCorp supports the CAISO’s proposal for developing a process for market participants to develop a gas nomogram. PacifiCorp is less concerned about the process being “streamlined” if it requires CAISO staff to develop some sort of new tool or automation. Based on the data shared by the CAISO in the technical workshop, it seems likely gas nomograms will continue to be infrequently used, and so PacifiCorp does not believe there needs to be a lot of time and effort devoted to “streamlining” the process. Rather, PacifiCorp would find it most beneficial if the process was clear and standardized so that market participants know what steps they need to follow to develop a gas nomogram.   

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

PacifiCorp appreciates the CAISO providing education to stakeholders on gas nomograms. The workshop gave PacifiCorp enough information to begin considering whether the Company would want to use the process for developing a gas nomogram. As such, PacifiCorp does not need any further educational sessions at this time. As PacifiCorp evaluates whether a gas nomogram is needed to manage reliability situations for the Company’s gas resources, PacifiCorp may reach out to the CAISO with more questions.

In PacifiCorp’s opinion, the conditions for activating a gas nomogram are properly restrictive and PacifiCorp does not recommend altering the operating procedures in place today. At this time, PacifiCorp does not support expanding the use of gas nomograms for purposes other than reliability.

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

PacifiCorp believes that the guidelines for eligibility stated by the CAISO in the Straw Proposal and in the technical workshop are reasonable. The guidelines are helpful for understanding what steps a market participant would need to take if they were interested in developing a gas nomogram.

7. Please provide any additional feedback not already captured.

No comment.

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

PGE appreciates the CAISO's efforts to enhance transparency and accuracy in fuel cost parameters as outlined in the draft gas resource management straw proposal. PGE directionally supports the straw proposal and shares the following perspectives: 

• PGE supports the use of a D+2 assessment for validating day-ahead and real-time market inputs but requests CAISO transparency on accuracy rates and validation against historical trends. 
• PGE is interested to hear additional stakeholder perspectives on how D+X might affect market outcomes 
• PGE recommends establishing clear, predetermined specifications for the fuel hubs, based on transparency, trading liquidity, deliverability, and correlations to gas market price fluctuations under dynamic market conditions. To ensure data accuracy, the CAISO should consider excluding extremely low trading liquidity or pipeline connectivity hubs. 
• PGE recommends the CAISO allow the negotiated commitment cost option to incorporate the blended fuel region parameters into the negotiated commitment cost framework. Under the fuel-blended option, PGE supports using the highest GPI values to establish a fuel price ceiling, ensuring generators can recover during price spikes while preventing inappropriate cost mitigation.  
• Overall, PGE appreciates this enhancement proposal, which promotes robust gas hub price governance and cost verifications. PGE recommends the CAISO periodically work with the stakeholder community to review and validate the fuel cost parameters after the new methodology is refined.

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

No comment

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

• PGE views the configurable default fuel multiplier option alone under 4.1.1 to not adequately capture extreme market conditions, such as periods of limited pipeline connectivity and/or insufficient trading liquidity. The manual RLCR process provides only a narrow adjustment window once per day, which further limits its capability. These constraints will under-represent the true fuel cost during stressed conditions and may not provide generators with a reliable recovery mechanism.  
• Regarding the negotiated commitment cost options outlined in section 4.1.2, PGE supports option 1 (to create a new full negotiated commitment cost option). PGE recommends creating a process similar to the NDEB process, with the GRDT reference allowing an SC to flag rankings of cost input.  
• PGE has the following feedback regarding the blended fuel region discussion (Section 4.1.3): 
  • What is the appropriate methodology for determining GPI values? (lowest, highest, average) 
    • PGE believes that the appropriate approach is to use the highest GPI values to represent the true fuel price ceiling, ensuring recovery during fuel price spikes and eliminating the risk of unnecessary cost mitigation.  
  • At what granularity should the weights be determined?  
    • This method assumes market participants would average the fuel region prices with weights. If so, PGE recommends that the monthly granularity be utilized to accommodate scenarios where an alternative fuel source was used in the short term.  
  • Should there be predetermined specifications for which hubs can be included in the blended fuel region?   
    • PGE recommends the following:  
      • Physical deliverability should be prioritized. The hub should represent gas that is physically deliverable to the generating resources.  
      • The hub must show interconnection connectivity with other major pipelines.  
      • Hubs showing minimum or extremely low trading liquidity should be excluded. Otherwise, the blended values may be inaccurately distorted. 
      • For validation purposes, PGE recommends that the hub have consistent and publicly reported historical data over the past 3-5 years.  
  • How should ISO collect and validate volumetric gas information?  
    • PGE is open to various options for information-sharing, including (1) the daily gas burn or gas nominations for PGE generation resources, (2) hub trading records, and/or (3) the percentage of gas procured from each hub. 
• For the above options regarding fuel cost parameter enhancements (questions 2 and 3), it could be beneficial to combine the two. For example, if the working group pursues the blended fuel region methodology, could that parameter also be incorporated under the negotiated commitment cost options? 

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

No comment

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

No comment

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

No comment

7. Please provide any additional feedback not already captured.

No comment

1. Please provide a summary of your organization’s comments on the gas resource management straw proposal, published on July 25, 2025, and gas resource management straw proposal stakeholder call, August 12, 2025.

No comments at this time.

2. Please provide any feedback regarding informing fuel procurement (section 3): the D+2 accuracy assessment, proposals for reporting market information, and proposal for bid set. Please provide any additional feedback on how to further incentivize D+2 supply offer accuracy

No comments at this time.

3. Please provide any feedback regarding accommodating cost variation (section 4): fuel cost parameter enhancements, and proposals for exceptional circumstances.

Sempra Gas and Power Marketing (SGPM) supports CAISO’s proposals to enhance fuel cost parameters and manage exceptional circumstances through GPI multiplier, negotiated commitment cost, and blended fuel zone proposals.

SGPM agrees with CAISO staff that market participants are required under the standard of conduct to operate units in a way that avoids unnecessary outages. The current mitigation framework disincentives market participants from procuring backup fuel to meet this standard of conduct guidance by imposing timelines to switch fuel zones in the MasterFile that do not line up with operational realities.

SGPM supports options that prospectively apply accurate fuel costs to commitment costs as well as incremental offers; relying on after-the-fact recovery distorts price formation for all market participants if units are committed based on inaccurate cost parameters with a price discontinuity for incremental energy production.

A comparable RTO/ISO with a structural market power mitigation test instead of conduct-and-impact test is PJM. PJM’s fuel cost policies, which are pre-approved by market monitor, allow market participants to file multiple fuel procurement policies to use in DA and RT offers and operations. This demonstrates that a process for more timely pre-approval and election to switch between fuel regions is just and reasonable under a structural market power mitigation paradigm. CAISO should consider how PJM’s implementation of fuel cost policies supports the simultaneous goals of the market monitor’s need for transparent and timely information on actual fuel costs, while allowing market participants flexibility to procure sufficient fuel from multiple locations when needed.

4. Please provide any feedback regarding managing gas burn limitations (section 5): proposed process to request a nomogram constraint.

No comments at this time.

5. Please provide a summary of your organization’s comments on the August 13, 2025 technical gas resource management workshop discussion on nomograms.

No comments at this time.

6. Please provide any feedback regarding the ISO’s proposed guidelines for eligibility for a streamlined process to leverage the gas constraint nomogram.

No comments at this time.

7. Please provide any additional feedback not already captured.

No comments at this time.