Comments on 5/22 call

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

The Salt River Project Agricultural Improvement and Power District (SRP), Arizona Public Service (APS) and Tucson Electric Power (TEP), collectively identified as the Arizona Utilities, appreciate the opportunity to comment on the Greenhouse Gas: Accounting and Reporting Straw Proposal and the May 22 meeting. The Arizona Utilities support CAISO's continued work to develop a flexible accounting and reporting framework that accommodates both state-mandated GHG requirements and voluntary corporate GHG reduction goals. Arizona does not have state-mandated GHG emissions reduction goals. SRP’s goals are set and monitored by its elected governing Board of Directors.

Overall, the Arizona Utilities believe that the approach meets the objectives identified by the working group, with the exception of the concept of a climate region and multiple residual rates. The Arizona Utilities remain concerned that a climate region will lead to inequitable treatment, further described in question #2.

The Arizona Utilities request clarification on whether the residual emission rate would only be available to reporting entities. Since this data should be aggregated and not reveal individual entity details, the Arizona Utilities encourage CAISO to consider making it publicly available.

The Arizona Utilities support CAISO’s proposal to provide reporting entities with flexibility in allocating MW and emissions. However, the Arizona Utilities recommend additional detail on how non-participating resources (NPRs) and contracts will be treated.

Additionally, the Arizona Utilities support continued discussions with stakeholders to clarify the implementation timeline, assess WREGIS’s ability to support the options proposed by CRS, and address the treatment of NPRs.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

The Arizona Utilities agree with the CAISO’s proposal to allow entities to have flexibility in allocating MW and emissions to their own inventory. However, CAISO should consider special rules for self-scheduled resources or resources running for reliability purposes that place these resources at the bottom of the stack.

For NPRs in a WEIM BAA, the Arizona Utilities would like to confirm that these resources are stacked similarly to a participating resource. Some data for registered NPRs should be available in the entity Master File, and the Arizona Utilities would like clarification on why participants would need to submit meter data to the CAISO. Additionally, the Arizona Utilities encourages CAISO to provide clarification as to whether NPRs, or registered participating resources with no bids for that interval, should be placed at the bottom of the stack, given they are not scheduled for market dispatch.

For jointly owned or partially owned resources, the Arizona Utilities appreciate the CAISO providing flexibility in terms of allocating MW. The Arizona Utilities encourage CAISO to retain additional flexibility in the final proposal that allows for alternative options to MW allocation, provided there is agreement among all resource owners.

For BAAs that are a mix of reporting entities and non-participants, the Arizona Utilities are concerned that the formula proposed by the CAISO may double count emissions if reporting BAAs stack resources individually but these resources are not pulled out of the average that will be used by the non-participating BAA. Numeric examples would be helpful to illustrate this concept.

The Arizona Utilities remain opposed to the concept of a climate region. The Arizona Utilities are significantly concerned that allowing entities to allocate only low-emissions resources to the GHG pricing region or climate region could bias the residual emissions rate. If cleaner resources are excluded from the residual calculation, the rate may no longer reflect the system as a whole. Further, the Arizona Utilities request clarification on why a separate residual rate is needed for the GHG pricing region or climate region and how it would be applied.

Moreover, the Arizona Utilities do not support the concept described in Option 3: User Choice where an entity in a climate region may strategically select resources for allocation to the climate region or pricing region and allow others to be part of the residual. This option will create multiple residual emission rates, none of which accurately represent the true emissions of the residual energy and may lead to inequitable treatment for entities that are not included in a climate or pricing region. Additional details on how climate regions might be identified or formed are needed. The Arizona Utilities continue to advocate for equal treatment for all participants.

Additionally, it is not clear how excess MW and emissions are handled under the merit order or User Choice approaches in situations where the GHG pricing region or voluntary climate region does not have sufficient load to utilize the full amount of excess. For example, if a reporting entity has 100MW of excess generation but the rest of the GHG pricing region only requires 75MW, it is unclear how the remaining 25MW would be treated. While the straw proposal appears to suggest that excess must be allocated to a single destination – either a GHG pricing region, voluntary climate region, or the residual rate – the Arizona Utilities encourage CAISO to clarify whether any flexibility exists under the merit order or user choice approach.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

The Arizona Utilities are open to validation either with a blanket attestation or an in-application agreement. For unconfirmed MW, the Arizona Utilities support flagging them as unconfirmed in the final report. However, the Arizona Utilities recommend that MW should still be assigned when at least one party has confirmed them with no active denials of ownership, even if the second party has not confirmed.

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

The Arizona Utilities prefer that the CAISO allow participants to have as much flexibility as possible in determining the appropriate emission rate, especially in the case where there is limited data available from supporting datasets such as EIA or EPA. Participants should be allowed to deviate from CAISO’s preferred emission rate development methodologies, so long as supporting information is provided to CAISO. CAISO should also clearly specify what supporting information is necessary for participants to deviate from preferred emission rate development methodologies.

The Arizona Utilities request CAISO to provide numeric examples of how hybrid and co-located resources’ emissions would be calculated for clarity. Examples with data from individual components and the resources in aggregate are helpful to understand the implications for these types of resources. 

The Arizona Utilities request clarification on how the report will handle either contract capacity where the emission factor is not known or other bilateral or intertie transactions where the emission factor is not known. These types of purchases or sales could be intra-market or come from outside of the EDAM/WEIM footprint.

Finally, the Arizona Utilities would like more information on how CAISO proposes to obtain emission factor data for newly commissioned resources or resources with significant changes that impact their emission rate (i.e., change in fuel type or efficiency improvements).

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

The Arizona Utilities prefer that the CAISO allow participants to have as much flexibility as possible in determining the appropriate emission rate, especially in the case where there is limited data available from supporting datasets such as EIA or EPA. Participants should be allowed to deviate from CAISO’s preferred emission rate development methodologies, so long as supporting information is provided to CAISO. CAISO should also clearly specify what supporting information is necessary for participants to deviate from preferred emission rate development methodologies.

The Arizona Utilities request CAISO to provide numeric examples of how hybrid and co-located resources’ emissions would be calculated for clarity. Examples with data from individual components and the resources in aggregate are helpful to understand the implications for these types of resources. 

The Arizona Utilities request clarification on how the report will handle either contract capacity where the emission factor is not known or other bilateral or intertie transactions where the emission factor is not known. These types of purchases or sales could be intra-market or come from outside of the EDAM/WEIM footprint.

Finally, the Arizona Utilities would like more information on how CAISO proposes to obtain emission factor data for newly commissioned resources or resources with significant changes that impact their emission rate (i.e., change in fuel type or efficiency improvements).

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

The Arizona Utilities appreciate the inclusion of alternative proposals submitted by CRS and recognizes the intent to align emissions reporting with REC ownership. However, the Arizona Utilities request clarification on whether WREGIS has reviewed and confirmed if the options proposed by CRS are technically feasible.

The Arizona Utilities also value the transparency and REC reporting completeness of Option 1 but is concerned there may be reporting burdens. Option 3 is more preferred because it appears to minimize the reporting burden on participants while providing a higher level of accuracy on the residual treatment of RECs tied to market energy, which is a priority of the Arizona Utilities.

Regarding Option 2, the Arizona Utilities would like more information on why RECs should be tagged in WREGIS for NPRs. Additionally, the Arizona Utilities seek clarification on whether references to “non-participating BAAs” in the proposal are intended to refer to NPRs, or if it reflects a different concept. The Arizona Utilities further request a clear definition from CAISO of what is meant by “RECs being ‘tagged’ in WREGIS.”  It is possible that RECs for these resources may have already been sold, so generating a REC on behalf of another entity may unintentionally double count them.  The Arizona Utilities would like to understand why Option 2 would be treated differently than Options 1 or 3.

In a future working group session, the Arizona Utilities would also like to discuss how the framework will consistently account for RECs that are obligated to be consumed within the BA, for example if a utility customer has a dedicated REC agreement.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

BPA appreciates the time and effort spent by CAISO staff to work closely with stakeholders to develop this approach.  The subgroup setting was particularly effective in eliciting productive discussion of concepts and brainstorming of options.  While BPA has made a policy decision to join Markets+, BPA intends to remain engaged in the CAISO’s GHG workgroup.  BPA will have resources and load obligations within the EIM/EDAM footprint and make sales to EIM/EDAM participants.  The outcome of the CAISO’s proposal is important in supporting GHG tracking and reporting needs of utilities participating in EIM/EDAM and ultimately across markets operating in the West.  The approach outlined in the straw proposal represents a solid step in meeting the objectives identified by the workgroup for the accounting and reporting effort.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

BPA supports the approach providing flexibility to meet the various needs of participating entities.  The CAISO specifically requested feedback as to whether there was a need for an entity using the “average” approach to have the ability to allocate excess energy across the residual rate, GHG pricing region, and/or voluntary climate region.  As an entity that envisions using an “average” approach, BPA believes there could be such a need.  For example, BPA could foresee a situation where an entity was willing to allocate 25% of its surplus to a voluntary climate region with the rest being allocated to the residual rate.  BPA suggests the CAISO not foreclose this flexibility.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

BPA recommends the CAISO provide a means for the seller and buyer to both indicate agreement.  Where one party fails to indicate mutual agreement, the CAISO should either 1) not reflect the arrangement in the accounting and reporting approach (where both parties are EIM/EDAM reporting entities) or 2) use a blanket attestation by one party with the MWs being market as unconfirmed (where only one parti is an EIM/EDAM reporting entity).

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

CAISO should allow flexibility for the entity to indicate the appropriate emission factor and, if none is indicated, then default to EIA/EPA emission factor or registered Master File emission factors.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

No comment.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

BPA is supportive of the approach described by the CAISO in the straw proposal as it reflects an approach that best navigates differing state policies on the treatment of RECs and null power at this time.  Treatment of RECs and null power is a state policy issue.  BPA does not believe it is appropriate for the market operator to require retirement of RECs or power to be treated as null absent clear, coordinated direction from western states on how to proceed.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

Comments on Greenhouse Gas Coordination

May 22, 2025 Working Group Meeting

Department of Market Monitoring

June 12, 2025

Summary

The Department of Market Monitoring (DMM) appreciates the opportunity to comment on the Greenhouse Gas Coordination Working Group meeting held on May 22, 2025, and the Accounting and Reporting Straw Proposal released on May 16, 2025.[1]^,[2] The working group meeting and the straw proposal document also included a presentation and an appendix regarding the issue of null power from the Center for Resource Solutions. The working group meeting and the straw proposal further specified and clarified how the accounting and reporting would function.

DMM continues to support the proposed accounting and reporting approach as a near-term means of incorporating non-priced greenhouse gas (GHG) policies into the extended day-ahead market (EDAM). The accounting and reporting approach would provide entities in regions with a tool for tracking emissions for compliance with non-priced GHG regulation and voluntary goals. The primary benefit of this approach is that it is a non-market process that attributes GHG emissions after the market runs, and as such would likely have minimal direct market impacts. DMM also recommends that the working group continue to explore the need for and possibly develop an in-market approach to ameliorating the scheduling and dispatch challenges posed by non-priced GHG policies.

Comments

Overview of issues and the accounting and reporting approach

The current market design only attributes GHG emissions to generation serving load in priced GHG regulation areas, and a mechanism to assign emissions to entities in regions with non-priced GHG regulations does not yet exist in CAISO markets. This poses two challenges:

1. There is currently not an in-market mechanism to constrain dispatch to prevent attributed emissions from exceeding a load serving entity’s (LSE) emissions threshold, and
2. Unspecified transfer emissions may pose challenges for LSEs and other market participants seeking to track progress towards satisfying state GHG regulations or other GHG emissions goals. The limited ability to track progress on meeting regulatory or other voluntary GHG related goals also limits market participants’ ability to optimize their portfolio of resources and energy contracts.

The proposed accounting and reporting approach would address the second of these two problems by introducing a method for accounting for GHG emissions from transfers into areas with non-priced GHG policies. This method is completely out-of-market, leveraging and enhancing existing post facto market dispatch data, as well as information on market participants’ contracted and owned resource capacity.

At a high level, the accounting and reporting approach compares a reporting entity’s load to its dispatched contracted and owned generation on a five-minute basis and tracks the greenhouse gas emissions associated with that generation, netting out generation attributed to GHG pricing regions.

• If the reporting entity’s generation exceeds its own load, the emissions associated with their excess generation will be allocated to the residual rate, a voluntary GHG climate region residual rate, or some combination of the two.
• If the reporting entity’s load exceeds their internal owned and contracted generation, then they are allocated GHG emissions from the residual rate, their voluntary climate region pool of emissions, or some combination of the two as is applicable.  
• Emissions from resources associated with entities not participating in the reporting would be assumed to be dispatched to serve their respective BAA’s load and assigned to that BAA.  
• If the generation assigned to the BAA load is less than or equal to dispatched generation, then no emissions would be added to the residual rate.
• In the case where non-participating generation exceeds its BAA’s load, the average associated emissions would be added to the residual rate.

One remaining question is how null power, or generation from resources without renewable energy certificates (RECs), would be accounted for. The Western Renewable Energy Generation Information System (WREGIS) issues and tracks RECs which are used by various entities for regulatory compliance and voluntary programs. The RECs assigned to a resource may be sold or transferred to another party, thus the rights to the non-emitting resource may be accounted for in some other entity’s portfolio. This creates a potential scenario where two entities may, on two different accounting ledgers, claim a resource’s low emitting generation. This issue arises from the existence of parallel and potentially conflicting systems of GHG accounting.

The Center for Resource Solutions (CRS) proposed three approaches to resolving this accounting challenge, with varying degrees of coordination between the CAISO and WREGIS and reporting of REC ownership. Common among the three proposed options is the exclusion of null power volumes from the residual rate calculation and the assignment of the residual rate to null power volumes for the purpose of allocating emissions.

DMM continues to support the accounting and reporting approach

DMM continues to support the development and implementation of the accounting and reporting approach. This approach would enable market participants to monitor and track GHG emissions for the purpose of satisfying regulatory requirements and voluntary emissions goals. This approach appears to largely address the need for a transparent accounting mechanism for allocating GHG emissions for LSEs in areas with non-priced GHG regulations or that have adopted voluntary programs.

One of the primary advantages of this approach is that it is entirely out-of-market and relies on after-the-fact data to allocate GHG emissions in areas without priced GHG regulations. Such an approach would likely have minimal direct market impacts. Moreover, the out-of-market accounting and reporting approach carries with it a smaller risk of unanticipated consequences when compared to an in-market approach, because it does not introduce new constraints or otherwise directly transform how the market optimization functions.

Regarding the question of how null power should be accounted for, DMM believes that stakeholders are best positioned to determine what data and metrics are needed to accurately represent their GHG emissions and satisfy regulatory and reporting requirements and goals. DMM does believe, however, that there are benefits to creating measures that are consistent between institutions, to avoid creating conflicting metrics and standards. Doing so would limit the potential for conflicting inter-institutional incentives and would enhance reporting and regulatory transparency.

A limitation of the accounting and reporting approach is that it does not directly provide a solution to the potential need to constrain dispatch to ensure that entities in locations with non-priced GHG policy meet their obligations. Further, an out-of-market approach could lead to market inefficiencies. Without an in-market solution, LSEs may be forced to procure and self-schedule higher-cost non-emitting resources to ensure regulatory compliance, when lower-cost non-emitting resources could have served load via transfers from other balancing areas.

It should be noted that the accounting and reporting approach would provide important information which would enhance a LSE’s ability to plan for future non-emitting capacity procurement and generation fleet needs. The reports generated by the accounting and reporting approach could also provide a strong basis to evaluate the need for an in-market dispatch constrained solution for entities in areas with non-priced GHG regulations.

As stated in DMM’s comments dated August 12, 2024, DMM agrees with the ISO that incorporating an in-market solution requires significantly more analysis to understand the market implications in full.[3] DMM also recognizes that the choice between in-market and out-of-market solutions to GHG emission and energy accounting for non-priced GHG regulation areas involves a number of trade-offs. DMM recommends that the ISO discuss those trade-offs with regulatory bodies and market participants. DMM also recommends that stakeholders and the ISO continue to explore whether an in-market dispatch constrained solution is needed, and what form potential in-market solutions could take.

[1]  Greenhouse Gas: Accounting and Reporting – Straw Proposal, California ISO, May 16, 2025: https://stakeholdercenter.caiso.com/InitiativeDocuments/Accounting-and-Reporting-Straw-Proposal-Greehouse-Gas-Coordination-Working-Group-May-16-2025.pdf

[2]  GHG Coordination Working Group meeting materials, California ISO, May 22, 2025: https://stakeholdercenter.caiso.com/StakeholderInitiatives/Greenhouse-gas-coordination-working-group

[3]  Comments on Greenhouse Gas Coordination 7-29-2024 Working Group, Department of Market Monitoring, August 12, 2024: https://www.caiso.com/documents/dmm-comments-on-greenhouse-gas-coordination-jul-29-2024-working-group-aug-12-2024.pdf

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

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 your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

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 your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

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 your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

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 your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

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 your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

CRS generally supports the Accounting and Reporting approach. However, proper accounting for null power and coordination with WREGIS in line with CRS’s proposal (Appendix A) will be critical to the success of this approach in meeting the objectives identified by the working group. If implemented without regard for the allocation of renewable generation using RECs, this approach could exacerbate inconsistency and create confusion regionally.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

No comment at this time.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

No comment at this time.

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

No comment at this time.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

No comment at this time.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

CRS appreciates the inclusion of Appendix A in the Straw Proposal. We continue to support coordination and data sharing with WREGIS for resource-specific allocations of WREGIS-registered renewable generation under the approach, and we recommend that the proposal for data sharing with WREGIS be adopted as described. We also continue to support proposals for null power reporting under the approach as presented in the Appendix, emphasizing that all proposed options rely on WREGIS data sharing. Our preferred option is Option 1; however, with WREGIS data sharing, Options 3 and 2 are also workable, in that order of preference. We welcome the opportunity to help address any concerns, explore challenges or alternatives, and provide additional information.

We would just like to reemphasize a core principle: generation cannot be allocated to more than one use. Double counting—whether across instruments, frameworks, or jurisdictions—undermines the integrity of the accounting system and renewable energy markets more broadly. If RECs associated with renewable generation in the market are used to allocate that generation and its emissions attributes outside the market boundary, they must be brought into the framework and accounted for transparently. This does not impose REC-based policies on all states, but ensures that those using RECs are accurately represented and protected from conflicting claims. Our proposals are designed to prevent double counting while preserving state flexibility. States that do not use RECs can continue to do so, using outputs of the framework and making any needed adjustments. But it is far more practical to start with a system that avoids double counting and adapt from there, than to untangle conflicting claims after the fact.

We remain open to alternative solutions, but stress the need to address this issue clearly and consistently.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

NV Energy appreciates the opportunity to participate in this stakeholder process and the CAISO’s and other stakeholder efforts to develop the straw proposal. However, NV Energy does not support the proposed accounting and reporting approach contained in the straw proposal. As currently presented, the proposal does not appear to align with the stated objective of ensuring accurate greenhouse gas (GHG) emissions accounting within the market residual rate.

At this stage, NV Energy recommends a simplified GHG emissions reporting framework favoring a single, comprehensive emissions rate over multiple rates. We suggest deferring the development of a more complex methodology until EDAM data becomes available, which would better inform a more complex approach if needed.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

NV Energy recommends holding off on the proposed reporting optionality at this time.  NV Energy would prefer to establish one GHG emission rate for the EDAM market prior to creating additional reports and optionality for individual participants. This would allow stakeholders the opportunity to review market emission data prior to make informed data driven design choices.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

No comment. 

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

No comment. 

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

NV Energy believes that the costs associated with substantial software changes should be borne by the market participants requesting the enhanced reporting. However, if stakeholders agree to maintain a simplified approach, such as utilizing a single emissions rate, then it would be reasonable to incorporate the associated costs into the market’s Grid Management Charge (GMC).

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

NV Energy strongly opposes the CRS proposal due to several fundamental concerns. First, the proposal conflates two distinct regulatory mechanisms, greenhouse gas (GHG) emissions accounting and Renewable Energy Credits (RECs), which operate on different timelines and serve different purposes. GHG emissions refer to the release of greenhouse gases into the atmosphere, primarily from energy production and consumption. Therefore, GHG emissions should be measured at each respective generator that is dispatched within the market. In contrast, CAISO defines a REC as representing the environmental attributes, but not the physical electricity, of one megawatt-hour (MWh) of renewable energy generation. RECs are used to demonstrate compliance with Renewable Portfolio Standards (RPS), which are separate from emissions accounting requirements.

The CRS proposal would inaccurately represent emissions within the market, thereby conflicting with the original problem statement the working group is attempting to address.

Problem statement: the lack of a mechanism that enables Load-Serving Entities and energy users to accurately account for energy and associated emissions used to serve load under regulatory and voluntary GHG reduction and clean energy goals.

By overstating emissions, the proposal risks misrepresenting the market-wide emissions rate and undermining the integrity of emissions data.

Additionally, the proposal assigns an emissions rate to null power, which inaccurately attributes emissions to energy that was not physically generated. This further distorts the emissions accounting process. NV Energy also emphasizes that each state has its own RPS and GHG emissions requirements. A policy that supports one state’s regulatory framework at the expense of another introduces unnecessary conflict and regulatory inconsistency. For this reason, NV Energy advocates for a simplified approach that begins with a single, market-wide emissions rate based on real-time market dispatch, rather than implementing a complex reporting structure that may propagate misinformation.

Finally, NV Energy maintains that CAISO or any market operator should not be placed in the position of mediating between regulatory compliance obligations and market participants. The market operator should not be responsible for REC reporting to WREGIS or for enforcing state-specific regulatory requirements. These responsibilities should remain with the appropriate regulatory agencies and individual market participants.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

The Oregon Public Utility Commission, Oregon Department of Environmental Quality and Oregon Department of Energy appreciate the opportunity to provide initial feedback on the California ISO’s May 16th Greenhouse Gas Accounting and Reporting Straw Proposal. As a state that has a long-standing greenhouse gas reporting requirement for electricity suppliers and with a climate policy requiring our largest utilities to meet declining emissions targets, accurate and standardized tracking of energy and associated emissions is critical.  Specifically, Oregon’s HB 2021 (2021) requires PacifiCorp, Portland General Electric Company, and the state’s electricity service suppliers to reduce emissions for electricity sales to Oregon customers by 80% below baseline levels by 2030, 90% by 2035 and 100% by 2040.

Since Oregon’s emissions reduction regulations do not rely on carbon pricing, but instead requires compliance with reduction targets, Oregon participants in the Energy Imbalance Market (EIM) are currently unable to receive deemed power from the market, despite Oregon utilities owning and contracting a growing base of zero-emissions generators. In the medium-or long-term (i.e., by 2030, 2035, or 2040) Oregon utilities will likely need an emissions-constrained dispatch solution from the market. This is influenced by Oregon’s geographic location next to, and transmission interconnectedness with, California and Washington - two GHG-priced program states.  However, in the near term a tracking and accounting only solution may work. Absent a market feature that enables deeming in non-priced states in the EIM and Extended Day-Ahead Market (EDAM), data representing the market dispatch and residual rate is likely the most appropriate approach for accounting of emissions from these purchases.  CAISO’s straw proposal is a step in the direction of enabling appropriate emissions attribute reporting by Oregon utilities from centralized market purchases.

Oregon supports the development and disclosure of accurate residual emissions rate data that reflects the best available information about the energy mix and emissions profile of the EDAM. At present, and in the absence of more granular data, the default rate of 0.428 MTCO2e is applied to all centralized market purchases reported under Oregon’s Greenhouse Gas Reporting rules.[1] If EDAM’s residual emissions rate data is robust, made available to market participants and regulators, and maintained consistently over time, it has the potential to be incorporated into Oregon’s greenhouse gas reporting regulations as the emissions rate or methodology applied to EDAM-sourced power.  This would allow the reporting to more accurately reflect the ghg content of these market purchases and the value the market may provide to utilities in meeting emissions reduction targets.

Improved emissions data would enhance the accuracy of reported emissions associated with market purchases, which is particularly important because Oregon’s utilities and regulators will rely on this reported information to assess compliance with those HB 2021 requirements. Accurately capturing any emissions reduction benefits resulting from the economic dispatch of non-emitting resources through the market not only supports compliance with Oregon’s carbon limitations but also informs near-term planning for how Oregon’s regulated utilities may leverage EDAM to achieve their emissions reduction goals at lower cost to customers. Additionally, a growing quantity of economic EDAM transactions carrying an artificially high MTCO2e will mask emissions reduction progress and could put annual compliance at risk, driving Oregon utilities to forgo the economic optimization of EDAM and instead adopt bidding strategies that place zero-emissions resources in a must-run position regardless of marginal cost.

[1] Oregon’s Greenhouse Gas Reporting Rules OAR Chapter 340, Division 215: https://secure.sos.state.or.us/oard/displayDivisionRules.action?selectedDivision=1538

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

Oregon’s greenhouse gas reporting regulations, administered by DEQ, outline how regulated electricity suppliers must report energy and emissions associated with owned generation, purchases, and sales to Oregon customers.[1] While these regulations do not currently allow centralized market transactions to be assigned an emissions factor other than the default rate of 0.428 MTCO2e/MWh, the allocation options presented in the Straw Proposal appear to offer pathways for alignment with Oregon’s reporting rules and flexibility for future regulatory oversight.

With this market feature, DEQ could pursue regulatory changes that take into account the more granular data made available by CAISO. To implement this, DEQ would need to undergo a rulemaking, engaging affected parties, to establish clear and specific language related to the allocation for excess generation. The flexibility offered in the proposal appears to offer the necessary options to support an update to the regulation to more accurately assign emissions from power acquired through EDAM.

[1] Oregon Greenhouse Gas Reporting Program: https://www.oregon.gov/deq/ghgp/pages/ghg.aspx

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

Oregon staff would appreciate additional information comparing the two options described.  Additional detail would help us better understand the operational and compliance impacts of each option, as well as the potential value relative to the costs of implementation.  It would be helpful to understand if any verification would occur, who this information would be made available to, and a clear explanation of the implications of flagging a transaction (e.g., how it affects reported data or outcomes) would be valuable.  Additionally, what would be the impact if a participant elects to not provide an attestation or additional information?

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

Oregon supports the use of EPA and EIA emissions factors, as they align with the methodologies used by Oregon and neighboring states for assigning emissions. However, we recommend that CAISO incorporate flexibility in the approach, including contingency options in cases where these data sources are no longer regularly available or are missing for specific facilities or units.

Additionally, since EPA and EIA data reflect prior-year operations, CAISO should consider allowing participants to petition for the use of self-reported emissions factors when they can demonstrate that a facility’s operating conditions have materially changed. For example, this flexibility would be important in cases where a generating unit has undergone a significant upgrade, conversion (e.g. from coal to natural gas), or where historical data is unavailable.

A clearly defined approval process for submitting and validating alternative emissions factors would help ensure transparency and consistency in such cases.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

Oregon regulators would appreciate additional information regarding the proposed implementation timeline and estimated costs to enable more detailed feedback on how these factors interact with the staging of work.

However, given that Oregon’s regulated utilities, Portland General Electric and PacifiCorp, are committed to participating in EDAM as early as 2026, it is ideal to establish a greenhouse gas accounting methodology at or near EDAM’s launch. Early implementation will allow regulators to assess the accuracy and format of emissions data and evaluate how it may be incorporated into reporting.  If found to be robust and accurate, this data, once incorporated into reporting rules, would support the utilities in tracking emissions associated with their market purchases.

Accurate emissions data, and specifically accurate residual rate data, is also critical for understanding EDAM’s role in contributing to emissions reduction opportunities and for informing long-term planning to meet Oregon’s climate goals.  The emissions data should reflect the benefit of centralized markets to economically dispatching non-emitting resources.

Oregon further encourages CAISO to continue exploring future mechanisms for deeming power to participants subject to non-priced emissions reduction programs. Under Oregon’s HB 2021, both regulated utilities are required to achieve a target of zero emissions for electricity serving Oregon customers by 2040. Eventually, deeming of specific resources may be an essential component to achieving that target.  Most importantly, accurately accounting for emissions within EDAM is an essential step in understanding how centralized markets can support compliance with Oregon’s Clean Energy Targets.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

Oregon’s greenhouse gas reporting and emissions reduction regulations are emissions-based and do not incorporate the use of tradable instruments such as RECs. In this regard, the rules were originally designed in 2009 to align with Western Climate Initiative essential requirements for mandatory reporting which prescribe an emissions-based reporting approach intended to maintain compatibility and avoid double counting within a GHG pricing regulatory construct, such as California’s Cap and Trade regulation. To align with the objectives of the Straw Proposal, CAISO should prioritize efforts to accurately reflect the energy and associated emissions that are economically dispatched in the market, and to develop a precise, emissions-based residual rate.

If CAISO pursues reporting to WREGIS or considers including null-adjusted data, we recommend that, in the interest of remaining neutral across different state policies and program types, CAISO also produce and provide data that excludes adjustments for null power or provides the null power data in a format that allows states to treat it in accordance with the state’s regulations. This dual reporting approach would enhance transparency and ensure that all market participants and states—regardless of whether they rely on RECs or emissions-based frameworks—can effectively utilize the data to meet their respective regulatory and policy needs. Additionally, CAISO should carefully consider the risks associated with sharing emissions or generation data on behalf of generators for the purpose of REC tracking in WREGIS. Since REC accounting is not a regulated function of the market, nor verified or enforced by market mechanisms, there is potential for unintended inaccuracies.

Oregon appreciates CRS’s intention for RECs to remain valid and trustworthy instruments. However, Oregon does not share CRS’s concerns with the Straw Proposal on this point. Oregon’s greenhouse gas reporting regulations described above exist in parallel with, not in concert with, Oregon’s renewable portfolio standard as well as Oregon’s consumer-facing reporting of emissions data through the Electricity Resource Mix. All three structures co-exist with diverging considerations for null power.

Oregon’s Clean Energy Targets, HB2021(2021), directly referenced DEQ’s existing emissions reporting rules, which, as described earlier were designed in 2009 to align with the Western Climate Initiative essential requirements for mandatory reporting. Those requirements prescribed an emissions-based reporting approach intended to maintain compatibility and avoid double counting within a GHG pricing regulatory construct. Thus, our focus on residual rate calculations is centered on the generation-based carbon pricing regulatory construct and not imputing GHG emissions via RECs. For additional context, Oregon provides the following information about these different programs: https://edocs.puc.state.or.us/efdocs/HAC/um2273hac17425.pdf.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

PacifiCorp applauds the hard work of CAISO staff, regulators, and stakeholders that worked towards developing the Accounting and Reporting approach framework (Framework). PacifiCorp acknowledges the diverse clean energy mandates faced by stakeholders, especially in the context of increasing organized market participation. The Framework aims at finding solutions to the following problem statement: 

The market lacks a mechanism that enables Load-Serving Entities and energy users to accurately account for energy and associated emissions used to serve load under regulatory and voluntary GHG reduction and clean energy goals. 

PacifiCorp agrees the Framework provides market participants subject to non-priced based climate policies, i.e., outside of a cap-and-trade/invest program, an avenue to detail emissions associated with market transfers than what is currently offered. The Framework explores variances to the market's unspecified emission rate, which will be utilized by market participants for their individual compliance reporting. While a static unspecified emissions rate has historically been employed, PacifiCorp believes the Framework allows market participants to demonstrate progress towards states’ clean energy goals and allows reporting entities to give states a more accurate accounting of the resources used to serve their state in a given year. Therefore, PacifiCorp supports the Framework moving forward but with the following modifications: 

• PacifiCorp believes null power should not be considered in the Framework moving forward. The inclusion of null power and renewable energy credits (RECs) in the Framework will create emissions that never existed, present challenges for market participants and states to meet their clean energy goals, and lead to unnecessary work, cost, and confusion on the emission intensity of the market. PacifiCorp agrees with the Washington Utilities and Transportation Commission presentation that noted that RECs are not an accurate representation of emissions and lead to an overstatement of emissions.  

• As described in previous comments, PacifiCorp does not believe that a voluntary climate region will provide the intended outcome as it will inherently inflate the overall residual emission rate of the broader market footprint. PacifiCorp strongly recommends this aspect of the proposal not be in effect for the launch of the Extended Day-Ahead Market (EDAM) but rather revisited once real-world data is attained from EDAM to quantify the impacts of market participation and meeting individual clean energy goals.  

• PacifiCorp does not support the ability to allocate energy and emissions to the company’s inventory and the residual rate. The Framework should only seek to determine the resources that serve the market footprint. PacifiCorp’s state greenhouse gas reporting rules do not currently allow reporting using a choice approach like the Framework. PacifiCorp recommends that stakeholders revisit the ability to allocate MW and emissions by choice to their inventory in the future once EDAM data is available.  

• As stated in the proposal, excess generation will be assumed to be given to the GHG pricing area prior to the potential voluntary climate region or residual rate under the “ISO Registration for Non-Participating entities” section of the proposal. PacifiCorp requests clarification on whether its excess generation would automatically be considered to serve the GHG Regulation Area, with the understanding that PacifiCorp will not be considered to be within a GHG Regulation Area.  

• PacifiCorp wishes to confirm whether if through the registration process, it can communicate a preferential allocation of committed capacity to its own load, in cases where there is excess generation, and cases where that committed capacity is economic.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

PacifiCorp recognizes that this Framework proposes a new reporting methodology and flags that state greenhouse gas accounting regulations would need to adapt to account for this new emissions calculation methodology. Today, many western states calculate emissions from unspecified electricity at a static emission factor and use data on owned generation, specified purchases, and specified sales to determine the emissions associated with generation used to serve a utility’s customers. As proposed, the Framework would allow market participants to choose which resources to count towards its own inventory versus allocated to the residual mix, a practice western state air regulators have not relied on as part of their greenhouse gas inventories. As a multijurisdictional utility, if states did not adopt this standardized Framework, there would be inconsistencies in reporting, which is one of the identified goals of this proposal. PacifiCorp believes states need to meet with stakeholders and update regulations to allow for reporting a market participant’s own inventory per the Framework, unspecified sales at the residual rate, and unspecified purchases at the residual rate for the Framework to be fully implemented as written.  

PacifiCorp echo’s previous regulator statements in the small working group discussions requesting a better understanding of how this choice allocation would work, both from a data availability and an impact standpoint, neither of which will be known until EDAM goes live.  

As such, PacifiCorp does not support the ability for market participants to allocate energy and associated emissions to the company’s inventory at this time as the framework should only seek to determine the resources serving the market. Once EDAM data is available, PacifiCorp is open to revisiting this concept again, however, ad hoc reporting adoption and inconsistent data splicing prior to receiving that data will lead to a distortion of what the actual emission intensity of the market is. PacifiCorp looks forward to future discussions with air regulators and CAISO to better understand the market data that will or could be available.   

Notwithstanding, when referencing the average emissions rate report currently published by the CAISO for 2024 and Q1 of 2025, the average emissions rate of the WEIM market footprint showed no instances when the market reached 0.428 MTCO2e-/MWh. PacifiCorp believes this proves that the overall market is progressively getting cleaner. In addition to the CAISO’s publication of the average emissions rate report, PacifiCorp contracted with the Brattle Group to conduct an EDAM participation benefits study which showed that increased EDAM participation results in a reduction in renewable curtailments thereby allowing cleaner resources to serve the market footprint and a cleaner market footprint. Allowing time to see the results of the market is prudent prior to implementing potentially costly enhancements of bifurcating data for individualized reports.  

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

PacifiCorp supports a blanket attestation for jointly owned resources where both parties agree to sign. PacifiCorp does not believe this process needs to be overly burdensome, and a simple attestation agreement from each utility suffices. 

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

PacifiCorp supports the usage of EIA/EPA emission factors, assuming the data is available, and registered Masterfile emission factors. Given most air regulators base compliance on emission factors based on EIA/EPA data, the market data should match that to reduce inconsistencies. In the case where EIA/EPA information is not available, for resources that are not registered within the Masterfile, there should be a mechanism to capture the emission factors based on the technology type. PacifiCorp is uncertain what ‘other self-reported emission factors’ would entail but believes validation of self-provided data should be required. 

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

PacifiCorp requests more discussion on the forecasted implementation costs of this effort and how those costs would be distributed between market participants requesting the enhancements in addition to what areas of the proposal would be the costliest to implement. 

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

PacifiCorp does not support any of the three CRS proposals. CAISO’s working group’s goal set out to identify the emissions intensity associated with the CAISO market. The Framework does not, and should not, contemplate renewable energy credit (REC) ownership, claims, or transfers as a part of this effort. The Framework does recognize that resources may be fully claimed and accounted for by parties other than the market participant, such as resources dedicated to exclusively serve certain customer loads, and accounts for these by removing them from consideration from the residual calculation.   

Null power considerations are important for renewable energy credit based accounting, like a renewable portfolio standard, or when offsetting emitting energy purchases to reduce an entity’s obligation. Null power assigns emissions to renewable energy resources in the name of reducing double counting when in fact, this generation never emitted in the first place. If PacifiCorp sold a resource into the market on an unspecified basis and retains the REC for compliance, then the market should be able to include that zero-emission resource in the residual mix. There were never emissions associated with that energy and PacifiCorp is not using that REC to reduce its obligation from an emitting resource. Many western energy stakeholders are concerned about the emissions from a wider-western footprint and the inclusion of null power will artificially inflate greenhouse gas market emissions and result in unfounded claims that the western market mix is dirtier than it actually is.  

Many regulators have either put forth or developed rules that determine how market participants count their emissions from market purchases. The Oregon Public Utility Commission correctly decided that RECs were not required to demonstrate compliance with HB 2021 because the legislation is an emissions reduction target, not a clean energy procurement target. The Washington Utilities and Transportation Commission is currently drafting rules on how to count resources bid into the market toward Clean Energy Transformation Act compliance Docket UE-210183. Adding null and REC considerations to the Framework may contradict or duplicate efforts in states and alter what is and is not counted as clean.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

PGE appreciates CAISO's efforts in this important initiative to provide insights on a more granular method of what constitutes unspecified source emission rates. To ensure an accurate representation of system emissions, PGE requests the publication of a residual rate that does not include REC/null power because RECs do not equate to greenhouse gas emissions. PGE does not support reporting requirements for Null Power and Renewable Energy Certificates (REC) (see response to Question #6 for more information).

PGE supports the Special Climate Region concept proposed in the accounting and reporting approach. PGE recognizes that our customers benefit from participating in markets to exchange surplus renewable energy with other jurisdictions with similar emission reduction policies. (See response to Question #2 for further details on proposal for flexibility of defined metrics in the climate region).

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

PGE appreciates the choices available to allocate MW and emissions to the reporting entity and to the residual rate. PGE recommends that an entity’s ability to change choice of allocation (Average, Merit Order, User Choice) be infrequent or on a specific cadence to enable consistent emissions accounting and reporting over time.

In developing the climate region, PGE requests flexibility and extension of choice in determining which excess energy can be allocated to the climate region based on the metrics developed the region. The purpose of the climate region is for like-minded entities to share in each other’s excess non-emitting energy. PGE proposes that the climate region be comprised of resources that are non-emitting only, regardless of the choices for allocations (average, merit order, and user choice). This could be achieved through bi or multi-lateral agreements between entities with specific clean energy goals or mandates.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

The extent of entity participation in the Emissions Accounting & Reporting tool is currently unclear. It is unclear whether all entities, including contracted resources/IPPs, would be able to participate and perform “handshake and flagging” in the application. Thus, PGE prefers Option 1: Blanket Attestation.

Relating to reporting MW and emissions allocation, PGE requests further discussion in accounting for deviations from the dispatch schedule for a shared resource. PGE seeks further conversation for the scenario outlined by Figure 2: Partially Owned Capacity % Allocation for Energy Dispatch:

The 100 MW shared capacity was all economically dispatched at 100 MW, then Entity A and Entity B will both receive 50 MW for energy assignment. In the next hour, both entities still bid 50 MW each, but CAISO dispatch only awarded 60 MW. There is a difference of 40 MW deviation from the schedule solely because of Entity B. To account for the deviation in the schedule, a potential outcome is that Entity A would be assigned 50 MW and Entity B would be assigned 10 MW. PGE is interested in further understanding the impact due to deviation from schedule and how to assign energy dispatch accordingly.

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

PGE requires an emissions factor (MTCO2e/MWh) that is approved by the Oregon Department of Quality (DEQ) for owned and contracted resources. PGE believes self-reporting options may be the best available option due to the limitations of the other two choices.

PGE believes there may be limitations in reporting emission factor in Master File due to the following:

1. The Master File emissions factor is used for California GHG transfers which is only a subset of the resources that would be registered and considered in the Emissions Accounting & Reporting
2. The unit of measurement of MTCO2e/MMBTU is different than the example shared by CAISO for Emissions Accounting & Reporting in MTCO2e/MWh
3. The Master File template is based on reporting for owned generation and for PPA for which the entity is also the scheduling coordinator (SC). For PPA contracts that PGE is not the SC for, PGE cannot provide the emissions factor.

PGE has heard concerns that EIA/EPA emissions data may not be publicly maintained or available in the future.  As such, given the limitations of the current Master File reporting and uncertainty with the future of EIA/EPA data, PGE supports a self-reported emission factor. PGE is open to discussing ideas for modifying Master File or other options as well.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

PGE looks forward to continued engagement on the implementation of Accounting & Reporting approach and appreciates the CAISO’s effort in providing any interim metrics and reports, such as the interim BAA metrics. 

As the reporting for the emissions may be relied upon for regulatory reporting purposes, PGE would like to request an audit or attestation of the annual report.

PGE further requests that implementation efforts for the Accounting and Reporting design take into consideration any future developments relating to the Extended Day-Ahead Market (EDAM) implementation, especially for EDAM early movers.

PGE also seeks additional detail on expected implementation costs.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

PGE does not support the CRS proposal. Changing the GHG Accounting and Reporting proposal to incorporate null power considerations disrupts PGE customer’s need for more accurate, granular representation of emissions, including a residual rate.

RECs do not equate to greenhouse gas emissions. There are varying eligibility criteria, compliance requirements, and definitions of renewable energy across state programs -- (1) what qualifies as a renewable energy resource, (2) age of facilities that qualify and (3) varying rules regarding when a REC is generated and when it must be used (retired), that may undermine the accuracy and comparability of emissions reporting.

The proposal to remove null power volume from the emissions factor will distort accurate representation of emissions on the grid at any given interval. There are significant non-emitting resources in the energy markets that do not qualify for RECs and under the CRS proposal, those are inherently null power. Legacy hydropower, for example, serves a significant percentage of PGE’s load and does not generate RECs.

Furthermore, this proposal is inconsistent with Oregon law, Oregon’s Department of Environmental Quality (DEQ) emissions reporting rule requirements and the views of our regulators. In Order No. 24-002[1], the Public Utility Commission of Oregon stated: “The text and context of the statute point unambiguously to the conclusion that compliance with HB 2021’s emissions reductions requirements need not be demonstrated through REC retirement.” DEQ emissions reporting is firmly rooted in reporting the emissions attributes of the underlying generating resource. “HB2021 requires us to consider and report the emission attributes of the underlying generating resource, and as such, emissions reported for compliance with HB2021 can only reflect the underlying generating resource.” 

Under Oregon Renewable Portfolio Standards, RECs and compliance requirements are already reported to Oregon state regulators and through WREGIS. Therefore, additional reporting to CAISO is duplicative and administratively burdensome. PGE also believes that is it not within CAISO’s jurisdiction or role to require REC reporting as the role of the ISO is to operate the transmission system independently of, and foster competition for electricity generation among, wholesale market participants[2].

PGE believes that Renewable Energy Certificates (RECs) are an imperfect tool to measure GHG emissions, and thus null power volumes do not meet the objective of accurate emissions reporting.

[1] https://apps.puc.state.or.us/orders/2024ords/24-002.pdf

[2] https://www.ferc.gov/electric-power-markets

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

The Public Generating Pool (PGP) appreciates the opportunity to provide comments on the Accounting and Reporting approach documented in the May 16th Straw Proposal. PGP also generally appreciates the CAISO’s continued efforts to work within the working group model on this important topic – while it has gone through some evolution, PGP’s perspective is that the working group model has worked well in this instance and supported the development of a straw proposal that reflects stakeholders’ positions and generally meets the identified objectives.

While overall PGP supports the straw proposal, there are two areas that likely need further development and discussion. These are: 1) the details and mechanics of the formation and implementation of voluntary climate regions; and 2) more detailed depictions of null power reporting and residual rate calculations. Particularly with respect to null power reporting, PGP would appreciate additional clarity with respect to when and how residual rates will be calculated with or without null power volumes included. It may be appropriate to have dedicated sessions to explore these topics to include additional detail in the final straw proposal.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

PGP supports the ability for reporting entities to direct the allocation of their MW and emissions as they choose. However, once a reporting entity selects an approach for the allocation of its resources and/or offers energy to be attributed to the GHG pricing region for a particular market interval, there should not be a re-allocation or change within the overall Accounting and Reporting approach based on a different selection by the reporting entity. This is to ensure that, for a particular market interval, each MWh is allocated only once and there is not double-counting of MWh or emissions.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

PGP does not have a position on this topic at this time but prefers the approach that is the most workable for the most market participants. There also may be multiple ways to flag unconfirmed MW in the final report – the easiest approach may be to include a footnote with the percentage of unconfirmed MW reported. This also may be something that evolves over time as market participants gain experience with the approach.

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

PGP does not have a position on this topic at this time.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

PGP does not have a position on this topic at this time.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

PGP does not have comments on this topic at this time. 

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

SDG&E believes the proposed Accounting and Reporting approach generally meets the objectives identified by the working group. The approach maintains alignment with market operations, as well as regulatory climate goals. While this is an additional task for the CAISO, it should be scalable and encourage broad participation.

SDG&E looks forward to remaining engaged in this initiative.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

SDG&E recommends that the allocation of MWs and associated emissions should follow the Merit Order approach, rather than allowing allocation “by choice.”

Allowing entities to allocate emissions at their discretion introduces the risk of inconsistent reporting, double counting, and distorted reporting results.

The Merit Order approach better supports reliable, data-driven climate reporting, and aligns with CAISO’s dispatch principles, and ensures consistency, transparency, and fairness in emissions accounting. This method reflects actual system operations and dispatch priorities, providing a more accurate representation of resource utilization and emissions attribution, and most closely aligns with GHG pricing mechanisms and regulatory requirements around emissions reduction.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

SDG&E supports the use of a Blanket Attestation for the validation and verification of buyer and seller arrangements. This method is a more practical and scalable solution that minimizes administrative burden while maintaining accountability.

We would like to note that the specific requirements and scope of the blanket attestation are unclear, and request that the CAISO provide additional detail on the expected content and frequency of this requirement.  

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

SDG&E appreciates the CAISO’s efforts to provide a flexible and robust accounting structure and supports the flexibility of allowing reporting entities to choose among EIA/EPA emissions factors, registered Master File emissions factors, or other self-reported emissions factors. This flexibility may help to accommodate the diverse regulatory contexts in the western region.

The most accurate way to report emissions values is to report what is actually charged by CARB at the time of emissions retirement. This would help avoid discrepancies that could arise from using generic or outdated emissions factors. However, this may be limiting as these values would only be available to California entities.

To better understand the implications of using the Master File, we request clarification on the following points: (i) How often is the Master File updated? Who is responsible for maintaining and verifying its contents? (ii) Are the emissions factors reported in the Master File generic, or do they reflect unit-specific or fuel-specific characteristics?

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

SDG&E has no comment at this time.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

SDG&E has no comment at this time.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

We would like to comment on two specific aspects of the proposed approach that are not elsewhere addressed: 1) ensuring accurate accounting of RPS and non-bypassable CFE resources, and 2) the proposed approach for treating storage as a load modifier.

Ensure RPS resources are allocated to the LSE that procures them: 

For accurate market-based emissions accounting by end users of electricity, it is best practice to ensure that any generation that was either A) procured by the utility on a mandatory basis (i.e. required by RPS) to serve load, or B) funded through non-bypassable charges (often nuclear) be allocated only to customers of that LSE. 

While participating LSEs can ensure that these are allocated to their load through use of the “manual stack” approach, the use of the “economic stack” approach may not result in such resources being matched to their load unless they are self scheduled or have a low ranking number, and use of the “average allocation” approach will result in a non-zero portion of each of these resources being released to the residual whenever the LSE’s generation exceeds load. This issue with the average allocation approach is especially problematic since this is the “default” method for any LSEs that do not otherwise specify an approach. 

Collecting additional data about which resource may fall into these categories and using that to prioritize the allocation of these resources to the LSE’s load would probably be the most robust approach, but may not be feasible or practical. 

At the least, we would encourage CAISO to consider chaing the the “default” allocation methodology for non-participating AOs to the “economic stack” method from the “average allocation” method. While not guaranteed, it is more likely for these resources to be self-scheduled and/or have low marginal costs so end up near the top of the ranking and be allocated to load.

Storage as load modifier may mis-allocate generation for an LSE's load obligation. The goal should be to time-shift generation, but a hybrid approach may be a better intermediate step: The current approach also proposes treating stand alone storage as a load adjustment. While this has the advantage of simplicity, it also has several important drawbacks and implications for accurate accounting.  Because stand-alone storage is often a transmission-level asset that does not count toward an LSE’s load serving obligation, using storage dispatch to modify the LSE’s load profile may result in a mismatch between the LSE’s load and the supply resources being matched to meet that load. For example, if stand alone storage is discharging, it will decrease the amount of LSE load, meaning that insufficient generation resources will be allocated to the LSE to meet its load serving obligation. 

Best practice would be to use storage to shift generation across time, allocating the generation mix to the storage asset while charging, decreasing the amount of generation that can be allocated to LSE load in the charging interval, and then assigning some mix of the stored generation mix to the discharged energy, which can then be allocated to load in the discharge interval. Such accounting approaches are currently being standardized through bodies such as EnergyTag (see section 1.6 of their Granular certificate scheme standard: https://energytag.org/wp-content/uploads/2024/12/EnergyTag_Granular-Certificate-Scheme-Standard-V2.pdf), which could be used as a model.

In the meantime, an intermediate approach that would retain the simplicity of the current proposal but be in better alignment with the objectives of the working group would be to treat storage as a generation modifier. Under this approach, when storage is charging, the LSE’s generation mix would be reduced by the amount of charging. The specific resources that would be reduced could follow any of the three allocation methods (average, economic, manual). When storage is discharging, it would be treated as a generation resource and added to the LSE’s generation mix, as a “storage” fuel type. Because this “storage” generation would not have a specific emission rate, it could be treated like null power, so that it would be assigned the residual emissions rate. This also helps ensure that any emissions for generation that is allocated to storage charging is not allocated to the LSE's load in that hour. Instead, when the storage discharges, emissions are allocated to the LSE at the residual emissions rate. 

While this approach would not actually maintain a ledger that tracks generation attributes across time, it would ensure that the amount of supply allocated to an LSE would match their load obligation in each hour, while the details of a more accurate time-shifting approach is established.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

Allocating resources by choice offers flexibility to accommodate different accounting needs. However, as noted above, there may need to be some guard rails to ensure accurate accounting. For example, as noted above, any LSE subject to RPS obligations should be required to keep these RPS resources in their own inventory (assuming sufficient load), rather than releasing them to the residual rate.

The ability of entities to easily choose an allocation method and stacking order can be facilitiated through effective software platforms that streamline this process for users, and make it easy to understand how the choice would impact their allocation. While the use of a manual stack approach could potentially be cumbersome if an entity owns many resources and has to rank each one, this process could also be streamlined by providing options such as category-based manual stacking rather than generator-specific stacking. An example of category-based stacking would be stacking based on fuel type, ownership, or other facility attributes.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

One of the most important features of either aproach is the ability to identify and resolve conflicting claims to the same generation. In application handshakes allow for more immediate feedback if multiple entities make conflicting claims, but even with blanket attestations, there is still a need to identify whether two different blanket attestations make overlapping claims. Thus, the main difference between the two approaches may be the user experience, rather than the robustness of the approach. 

We would recommend for the sake of transparency that any unconfirmed MW be flagged in the final report, including in any summary statistics and visualizations of the data. 

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

Annual average EFs will introduce substantial inaccuracies; heat rate curve methods are as simple to implement and are already in use in other ISOs for emissions accounting. Including flexible requirements will allow the best approach to be used as the data landscape and implementation details evolve. 

We have found that for hourly accounting systems, annual average emissions factors are likely not sufficient, and we would urge the flexibility to use more dynamic emissions measures such as heat rate curves. While this may seem more complex on the face, such an approach is already in use in MISO for emissions accounting, and makes use of publicly-available data, meaning that all that is required is the EIA plant and generator IDs of each resource in the system. See more details about the MISO implementation of this approach here: https://miso.singularity.energy/GRETA_documentation.8afca3.pdf and here: https://miso.singularity.energy/CarbonFlow_documentation.954093.pdf (pg 12).   

While the use of static, annual-average, generator-specific emissions factors has been the status quo approach for estimating annual total emissions, our analysis has found that such approaches are not appropriate for accurate, temporally granular allocation of emissions, such as on a 5-minutely basis as proposed. This is due to the fact that generator heat rates (and thus emissions factors) change from interval to interval based on various factors, and that certain generators can fuel switch over time.

Furthermore, the emission factors published by eGRID are only published at the plant level, rather than generator level, meaning that their use may mis-allocate emissions across multiple generators located at the same plant, which may or may not be owned or contracted by the same entity. We compared hourly emissions calculated using eGRID plant-level emissions factors to measured hourly CO2 emissions data reported to EPA CAMPD using CEMS devices, and found that eGRID factors mis-estimated hourly emissions totals by 17% in CAISO, 12% in BANC, and 45% in PGE, for example. Use of generator-specific emissions factors available through public data sources such as the Open Grid Emissions dataset reduced these errors, and use of generator-specific heat rate curve models (which Singularity has calculated based on publicly-available data) proved to most accurately estimate emissions for these regions.

Rather than requiring one specific approach or dataset, we recommend writing the requirements more flexibly to use "best practice data and methods to be determined at the time of implementation." Language like this will allow the report to keep up with the evolving landscape of available data and methods, especially as the future availability of federal datasets is at risk.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

The implementation of this approach will require an workflow for both LSEs and CAISO to submit, view, modify, and interact with a wide variety of data, and much of the cost will depend on how efficiently and intuitively the application can facilitate these workflows. The cost will also depend on the extent to which any software will need to be built from scratch rather than relying on existing platforms and tools. 

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

No feedback

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

Please see the attached letter for comments from the Washington Utility Regulators.

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

Please see the attached letter for comments from the Washington Utility Regulators.

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

Please see the attached letter for comments from the Washington Utility Regulators.

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

Please see the attached letter for comments from the Washington Utility Regulators.

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

Please see the attached letter for comments from the Washington Utility Regulators.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

Please see the attached letter for comments from the Washington Utility Regulators.

1. Please provide your overall feedback and/or recommended enhancements to the Accounting and Reporting approach and to the extent you believe it meets the objectives as identified by the working group.

WPTF appreciates the opportunity to provide these comments on the GHG Accounting and Reporting Straw Proposal. We provide two general comments below, followed by comments on specific elements.   

The need for accurate, granular, and public market GHG data 

As WPTF has noted in the subgroup discussions, there are strong signals that the Trump Administration intends to eliminate the collection and reporting of GHG data by the Environmental Protection Agency, and possibly, the Energy Information Agency. This suggests that market participants, stakeholders and the public will not have access to reliable and transparent data, such as that provided by EGRID, in the future. 

The GHG Reporting and Accounting Approach provides an important opportunity to help fill the gap that would be left by the elimination of those programs. CAISO should aim to provide a complete and accurate publicly available market data set tabulated on at least an hourly and annual basis. This data should include information on the market footprint as a whole, volumes allocated to reporting entities and the residual data set. 

Provision of this data would serve policymakers in understanding changes in the electricity mix and how it is utilized over time and would also enable regulators to develop more accurate GHG reporting methods to incentivize changes in behavior under various programs. Potential use cases for improved GHG accounting using the residual data set include non-contracted energy storage that may be imported on a specified basis to the GHG pricing programs and emission factors for use of grid energy in production of renewable fuels for use in clean fuel programs. The data would also be invaluable to numerous non-governmental organizations and the public generally.

CAISO indicates that it will provide advisory reports to reporting entities on a monthly basis so that the entity can verify the validity of what is reported. WPTF supports this approach, but requests that CAISO clarify at what point the monthly data will be finalized and provided to each entity for the year. 

The Straw Proposal indicates that if a reporting entity elects to calculate a residual emission rate, CAISO will provide the hourly residual rate data set. However, the paper does not specify exactly what will be in that data set. WPTF recognizes that this topic is still under discussion in the subgroup, but recommends that CAISO include details about the data set in the next iteration of the proposal. 

Terminology 

WPTF recommends that CAISO clarify and precisely use terminology throughout the proposal to avoid confusion. First, CAISO used the term “transfer” throughout in discussing accounting of energy and greenhouse gas (GHG) emissions associated with serving a reporting entity’s load. This is inappropriate and confusing: while the attribution of energy and emissions (i.e. deeming) of energy and associated GHGs to a state with a GHG pricing program relies on a physical transfer of energy into the state from elsewhere in the EDAM or WEIM footprint; the GHG Accounting and Reporting approach does not. Rather, it simply allocates energy and GHG dispatched by a reporting entity’s owned and contracted resources to that entity, regardless of where those resources are located and whether there was a physical flow of energy into the BAA where the reporting entity was located. CAISO should eliminate use of this term with respect to the GHG accounting for serving load.  

Second, the Straw Proposal seems to use the terms attribution, assignment, and allocation interchangeably. To avoid confusion, we suggest that CAISO use the term “attribution” to refer solely to the dispatch function that deems energy and GHGs to the GHG pricing areas. CAISO should also select a single term “assignment” or “allocation” to refer to the non-dispatch function of accounting for energy and GHG associated with serving a reporting entity’s load. 

2. Please provide your organization’s feedback on the ability for a reporting entity to allocate MW and emissions by choice to their own inventory, to the residual rate, and if applicable the GHG pricing region or voluntary climate region.

WPTF has a number of questions and comments on the Registration Process, which we hope to see clarified in the next iteration of the Straw Proposal. It was unclear where in this comment template to include such feedback, so we have included it here.

The Straw Proposal indicates that if a “reporting entity has any out-of-market purchases or any WEIM non-participating resources that should be included, it will be up to the reporting entity to separately report these to the ISO.”  WPTF does not object to this provision, but questions whether it is necessary, given that entities can readily incorporate information on energy and emissions from any non-market resources for their internal accounting. 

The CAISO seeks feedback on whether null power reporting should be required or not. WPTF strongly opposes any requirement that would obligate reporting entities to report null power. As discussed elsewhere, regulators in different states (and even within the same state) differ on whether null power is relevant to GHG accounting. As the determination of whether to report null power is fundamentally a policy issue, it would be inappropriate for CAISO to impose such a requirement.  

WPTF supports giving reporting entities the options to select between the three methods (average, merit order, user choice) for treatment of excess generation. However, we believe that once elected, the method chosen should be locked for a set period, such as three years, unless there is a regulatory change necessitating a change.  

Considerations regarding the treatment of excess energy for reporting entities in a voluntary climate region require further discussion.  

With respect to registration of resources for non-participating BAAs, we note that because of the decision that GHG Reporting and Accounting support entities at the load-serving entity level, this should more appropriately refer to registration for non-reporting entities, not non-participating BAAs. Within any given BAA within the market footprint, there may be both reporting entities and non-reporting entities. If some entities within a BAA are reporting, the load and production of the dedicated resources to those entities should be removed from the overall BAA load and resource production. Similarly, any production dedicated to reporting entities located outside the BAA should be removed. The remaining production of resources in the BAA (i.e. non-dedicated production) should be considered as serving the load of that BAA first. We support assignment of any non-dedicated production in excess of non-reporting entity load in the BAA to the residual supply using the production average. 

WPTF is confused by the statement on the bottom of page 14 of the Straw Proposal that states “In cases where the non-participating BAA has generated more than its load, those excess MW will be allocated to the GHG pricing area.”  For GHG pricing states, energy and emissions will be attributed (i.e. deemed) to the GHG pricing area by the market dispatch based on the GHG bids of participating resources outside the GHG pricing area. If a BAA partially overlaps a GHG pricing area, and the participating entity elects to have the GHG pricing area load delineated so that the load can be served by deemed specified imports, then we assume that the GHG pricing attribution would apply. Or the entity could elect to have excess production from its load area outside the GHG pricing area be allocated to any shortfall of its load inside. However, if the participating entity has not elected to have the GHG pricing area load delineated from the rest of the BAA, then we assume that imports to that GHG pricing area would be determined by the Multijurisdictional Retail Provider GHG accounting provisions of the GHG pricing regulation. Thus, this provision in the Straw Proposal seems incorrect. CAISO should consult with affected entities to clarify what is intended.  

3. Please provide your organization’s feedback on if the validation and verification of buyer and seller arrangements as either a blanket attestation or an in-application agreement. For any unconfirmed MW, if or how should these be flagged in the final report?

WPTF prefers an in-application confirmation by both parties for contracted resources. This will be important to prevent dual claims to the same energy as a resources contractual arrangements change. However, we would defer to others on whether this approach would be overly burdensome.

4. Please provide your organization’s feedback on the flexibility of allowing choice on using: EIA/EPA emissions factors, registered Master File emission factors, or other self-reported emission factors.

The CAISO has identified three potential sources of emission factors for resources: technology, fuel type and market participation model from the ISO master file, publicly available information from EPA and EIA, and self-reported information from the resource participant. As a starting point, WPTF believes that it would be far preferable to use a single consistent data set of emission factors for all resources within the footprint across all reporting and non-reporting entities. Of the three potential sources of information, EPA’s annual average emission factor for resources would best meet this objective, and importantly, has been the primary basis for the development of state-assigned emission factors for electricity imports and purchases. However, we are concerned about the Trump Administration’s effort to terminate EPA’s collection and reporting of GHG data. (The same applies for EIA.) For this reason, we suggest that CAISO consult with state air regulators responsible for both GHG pricing programs and non-pricing programs to discuss options for development of a coherent database of emission factors for all resources within the market footprint.  

We also want to take the opportunity to comment on the treatment of storage resources here as there is not another natural section in this template. The proposed approach to treatment of storage resources seems to presume that all storage resources would be owned by or contracted to a reporting entity (or non-reporting entity and picked up in the BAA level comparison of production to load).  For storage resources, regardless of type, that are owned or contracted to a reporting entity, modification of the reporting entity’s load is an appropriate way to account for energy and emissions associated with charging and discharging those resources. However, this approach would not be sufficient for stand-alone or hybrid IPP-owned storage resources that are not contracted to a reporting entities. Those resource owners may wish to accurately track the emissions associated with grid charging (which would be provided from the residual supply) across discharge intervals to enable more accurate accounting of GHG emissions associated with discharging. Such accuracy would be important to ensure appropriate pricing incentives under GHG pricing or clean fuels programs. WPTF understands that CAISO may be reluctant to model and track GHG emissions across all stand-alone and hybrid resources as supply resources due to the additional complexity. Instead, we suggest that CAISO allow IPP-owned storage resources to be reporting entities. The ability of resource owners to accurately track emissions across charging and discharge intervals would be a necessary to enable regulators to develop better accounting rules for storage.  

5. Please provide your organization’s recommendations on how to stage implementation work on the Accounting and Reporting approach and any comments associated with the costs of this effort.

No comment at this time.

6. Please provide your organization’s feedback on the CRS proposals and the extent to which you recommend these proposals should modify the Accounting and Reporting approach. These proposals are located in Appendix A of this straw proposal.

With respect to the CRS Proposal, WPTF does not oppose CAISO providing the data suggested to WREGIS for generators and reporting entities that have requested the data to be shared. However, we would strongly oppose sharing this information where it has not been explicitly requested or approved by the affected parties.  

Regarding the CRS proposal for null power, WPTF notes that neither state regulatory programs, nor electricity market participants and stakeholders have a common view on null power and how it should impact GHG emission accounting. It would therefore be completely inappropriate for the CAISO to impose requirements in the GHG Accounting Reporting for proof of REC ownership or to dictate requirements for null power.  For this reason, we do not support any of the three options that CRS has proposed. Instead, we recommend that the CAISO adopt the structure being developed within the subgroup. Specifically, CAISO should provide an hourly residual data set for reporting entities and the public, categorized by fuel type. However, any hourly null power included in the residual supply should be aggregated across null power fuel types.