Comments on Straw Proposal

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

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, are supportive of the overall direction of the Draft Final Proposal but have concerns with the proposed treatment of residual emissions. The Arizona Utilities understand that CAISO’s intent in establishing a separate residual emissions rate for GHG pricing regions is to reflect the regulatory overlay and carbon costs impacts associated with programs like California’s Cap-and Trade and Washington’s Cap-and-Invest. However, the Arizona Utilities remain concerned that the concept of separate residual emissions rates for the GHG pricing regions and the broader market may allow entities to retain lower-emitting resources in the pricing region while assigning higher-emitting resources to the market-wide residual, which could create inconsistencies in emissions reporting. Further, the Arizona Utilities do not support an excess energy option methodology that allows entities to choose which resources are assigned to a GHG pricing region and which are assigned to the residual rate. The Arizona Utilities encourage CAISO to ensure that the residual emissions rate is applied consistently and equitably across the market.

2. Does your organization plan to use the public report data?

The Arizona Utilities are evaluating the public report data and potential use cases, particularly for the Fuel Report and Residual Data Set.  The Arizona Utilities request that CAISO publish a timeline of implementation with a targeted production date to better understand how the data might be utilized.

3. Does your organization plan to request the private report data?

The Arizona Utilities are also evaluating use cases for the private report, pending the implementation timeline from CAISO. The Arizona Utilities recommend including the stacking order of resources each hour as part of the private report. This would allow entities to perform any needed post-processing to separate out embedded loads or other loads, resources, or transactions that require special treatment. While this data is able to be calculated by the report participant, it would be tedious to calculate every hour for the merit order and even for user choice methods. 

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

The Arizona Utilities generally agrees with the registration policy items proposed.  However, as stated in question 1, the Arizona Utilities are concerned with the proposed approach to create separate residual emission rates for the pricing regions.  Moreover, the Arizona Utilities are opposed to an approach where entities can pick and choose which resources should go to which residual emission rate, as described in the user choice example. The Arizona Utilities requests clarification from the CAISO on whether this example aligns with the description of the user choice method described on page 14, where it states that excess would be assigned the weighted average emission rate and assigned to either residual. This description implies that all resources that are excess are treated the same way and go to one residual.  Overall, the Arizona Utilities remain in favor of allowing entities to choose a method to stack resources, but not with the concept of multiple residual emission rates.

The Arizona Utilities agree with CAISO’s proposal for the treatment of unconfirmed transactions.  For resources that are partially owned, the Arizona Utilities request that CAISO be less prescriptive in the options for treating different contracts.  There may be cases where shares of jointly owned units do not fit into the options described and participants may need more flexibility in assigned ownership by hour.

For the merit order stacking method, the Arizona Utilities request clarification if the GHG adder would be included in the stacking economics.  For entities outside of a pricing zone, the GHG adder should be excluded when determining a stacking order. Additionally, the Arizona Utilities request clarification on how non-participating resources (NPR) and self-scheduled resources will be positioned in the merit order stacking method.

The Arizona Utilities suggest CAISO provide dedicated time in a future meeting to review options and numerical examples for stacking NPRs and transactions both internal to the market footprint, as well as imports/exports external to the footprint.  These types of sales and purchases will impact the stack order, and therefore the residual emission rate. 

Finally, the Arizona Utilities request that the CAISO consider an option for entities that are opting out of the private report to be able to designate resources associated with null power.  This will allow entities to optionally provide more detailed information to CAISO that could impact the residual emission rate.

6. Please provide your organization’s feedback on the calculations for various fuel types.

For hybrid resources, the Arizona Utilities agree that the non-storage component’s fuel type should apply to the emission factor when charging exclusively from on-site generation. For co-located resources, the Arizona Utilities request confirmation that when the off-grid charge indicator (OGCI) is inactive and the reporting entity has load, battery charging increases the entity’s load, and the associated emissions are captured by the resources that ramp to serve that incremental load.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

The Arizona Utilities request clarification on the purpose of the Fuel Report. This report currently has blank lines for each fuel type each hour. The Arizona Utilities questions if the final report would contain data in these fields or more information on the purpose of these items.

The Arizona Utilities also requests that the CAISO review the confidentiality of the data on the Excess Energy Option tab.  If there are only 1-2 entities in a category, it may be possible to deduce another entity’s choice and the GWH of excess energy they contributed to the residual.

8. Please provide the ISO with any additional feedback not already covered.

 No additional comments at this time.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

BPA appreciates the CAISO’s efforts to develop the Accounting and Reporting approach. The draft final proposal is a result of significant stakeholder discussion facilitated by CAISO staff. BPA supports the approach taken in the draft final proposal with one caveat around null power discussed in the response to question 5 below.

2. Does your organization plan to use the public report data?

Given BPA’s policy direction is to join Markets+, it is not clear whether WEIM data will be available and of use to BPA before market transition. Either way, BPA supports CAISO making publicly available the data as described in the draft final proposal.

3. Does your organization plan to request the private report data?

Given BPA’s policy direction is to join Markets+, it is not clear whether WEIM private report data will be available and of use to BPA before market transition. Either way, BPA supports CAISO providing these reports for reporting entities that request it.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

N/A

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

BPA provides comments on two aspects:

1. Out of Market purchases

BPA understands there are complexities with including reporting entities’ out of market purchases that are imported into the market. However, not including these purchases in the reporting on a uniform, consistent basis can skew the residual data and emission factor. Without knowing the magnitude of these purchases for participants in EDAM, it’s difficult to determine whether the complexities of implementing outweigh the benefits of a more accurate residual emission data set. BPA does not oppose CAISO moving forward with inclusion of out of market purchases as optional at this time, but requests the CAISO revisit this topic when more information is available.

2. Null power

Regarding null power, BPA does not support the CAISO requiring that reporting entities report null power. Rather, this should be optional. Considerations for null power are needed because of double counting provisions in Washington’s Clean Energy Transformation Act (CETA). Washington utilities subject to CETA may need to report power as null to preserve their ability to use RECs for CETA compliance. However, many other state reporting and reduction programs are concerned with the fuel type of the power, without regard to the disposition of RECs, and utilities in those states may not have a need to report power as null. It is not necessary to require null power reporting to strike a balance between state programs; providing the ability and option to report power as null is adequate.

6. Please provide your organization’s feedback on the calculations for various fuel types.

BPA supports the flexibility of allowing reporting entities to indicate the appropriate emission factor for their resources and does not have concerns with using the Master File to source this information. Using EIA/EPA data or a CAISO calculated emission factor in the event an emission factor is not included in the Master File is reasonable.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

BPA supports the public report data elements.

8. Please provide the ISO with any additional feedback not already covered.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

Comments on Greenhouse Gas Coordination

July 21, 2025 Working Group Meeting

Department of Market Monitoring

August 20, 2025

Summary

The Department of Market Monitoring (DMM) appreciates the opportunity to comment on the Greenhouse Gas Coordination Working Group meeting held on July 21, 2025, and the Accounting and Reporting Draft Final Proposal released on July 18, 2025.[1]^,[2] The working group meeting focused on identifying the differences between the straw proposal and the draft final proposal. The draft final proposal presents the accounting and reporting approach in full, while also identifying key differences between the straw proposal and the draft final proposal.

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 EDAM and WEIM markets. The accounting and reporting approach would provide entities with a tool to track emissions for compliance with non-priced GHG regulations and voluntary goals. The primary advantage of the accounting and reporting approach is that it is a non-market process that allocates GHG emissions after the market runs and, as such, would likely have no direct market impact.

DMM supports the non-market accounting and reporting approach as a near-term implementable solution. However, we also recommend that the working group continue to explore the need for an in-market approach to resolving the scheduling and dispatch challenges posed by non-priced GHG policies, and develop such an approach as a future enhancement if deemed necessary. 

DMM supports many of the changes in the draft final proposal because they improve the transparency and flexibility of the accounting and reporting approach for a wider range of resources and reporting entities. However, we note that the change to make reporting of out-of-market and WEIM non-participating resources optional may reduce the accuracy of the residual rate.

Comments

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 load serving entities (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. Therefore, 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.

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 several 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.

The accounting and reporting approach leverages existing market data to assign emissions to reporting entities

At a high level, the accounting and reporting approach compares a reporting entity’s load to its dispatched, contracted, and owned generation on an hourly basis, tracks the emissions associated with that generation, and nets out the generation attributed to GHG pricing regions.

• If, after GHG attribution adjustment, a reporting entity’s owned and contracted generation exceeds its load, its excess generation will be allocated to the residual rate based on their selected methodology.
• If, after GHG attribution adjustment, a reporting entity’s owned and contracted generation is less than its load, none of its generation will contribute to the residual mix and the reporting entity will be allocated GHG emissions from the residual rate.
• For reporting entities that overlap with GHG pricing regions, there are generation adjustments for the sharing of GHG with the GHG pricing regions the reporting entity overlaps with.

This accounting process leverages existing market data, WEIM participating resource data, and the contracted resource data provided by the reporting entities. This data is used to determine the emissions associated with a reporting entity’s owned and contracted generation, the calculation of a residual rate based on the emissions from excess energy, and the assignment of excess energy emissions to reporting entities on the basis of the load not covered by owned or contracted generation. 

The accounting and reporting approach does not manage resource dispatch or emissions thresholds

The current market design only attributes GHG emissions to generation serving load in priced GHG regulation areas. 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 not an in-market mechanism to constrain dispatch to prevent attributed emissions from exceeding a load serving entity’s (LSE’s) 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 voluntary GHG related goals also limits market participants’ ability to optimize their portfolio of resources and energy contracts to meet those goals.

The accounting and reporting approach described in the draft final proposal addresses the second concern by introducing a method for allocating emissions to reporting entities.[4] The approach is wholly out-of-market and uses a combination of post-facto market dispatch data and reporting entity ownership and contracting data to allocate emissions to reporting entities. DMM supports this approach to addressing the second concern listed above, but DMM continues to recommend that the ISO and stakeholders continue to explore whether an in-market solution is warranted for the problems that arise from the first issue.

Changes in the draft final proposal may decrease the accuracy of the residual rate, but generally appears to increase transparency and flexibility of the accounting and reporting approach

Accounting for non-participating and out-of-market generation and null power

One of the draft final proposal’s key differences from the straw proposal is how the accounting and reporting approach will deal with non-participating, out-of-market procured generation, and null power.[5] For these elements of generation accounting, the ISO modified its proposal to increase the flexibility of how generation in those categories is accounted for by each reporting entity. The apparent need for additional flexibility in how those items are reported is due to the variation in reporting requirements between states and individual reporting entities. DMM recognizes that the accounting and reporting approach is designed as a tool to facilitate accurate reporting for non-priced state regulatory and voluntary GHG emissions programs, and that the reporting requirements vary. However, the introduction of flexibility into reporting requirements may lead to less accurate estimations of the residual rate or more ambiguous reporting categories.    

One such change from the straw proposal was that the reporting of out-of-market and WEIM non-participating resources became optional. These resources present reporting challenges because the ISO would lack output information and emissions rate data, due to the lack of internal dispatch and Master File data for those resources. Furthermore, the regulatory bodies that reporting entities report to may have differing approaches to accounting for out-of-market resources.

While DMM recognizes the variation in regulatory requirements and the ISO’s lack of visibility into out-of-market and WEIM non-participating resources, it is important to recognize that not requiring the reporting of these resources reduces the accuracy of the residual rate. The reduced accuracy comes from the possibility that a reporting entity’s excess energy status may be contingent on their unreported energy. Including out-of-market or WEIM non-participating energy may mean the reporting entity would have excess energy that would contribute to the residual rate. This would in turn affect the emissions rate mix used to determine the value applied to other reporting entities. Because of this, DMM believes that for the sake of transparency and accuracy, the required reporting of out-of-market and WEIM non-participating energy is the better option. We do, however, appreciate reporting entities’ need for flexibility due to differences in regulatory requirements and, considering the out-of-market nature of the accounting and reporting approach, see this as a reasonable path forward.

The ISO also opted for a more flexible approach to resolving the complications of accounting for null power. The ISO notes in the draft final proposal that there are differing approaches to reconciling null power between regulatory bodies. The ISO in its proposal opted to provide parallel reports that report generation totals, and separately list unconfirmed transactions and null power, which will enable reporting entities to account for null power and unconfirmed renewable energy certificates (RECs) in line with their respective regulatory requirements. DMM supports this resolution to the issue of how null power is accounted for because it enhances flexibility while also maintaining transparency.

Climate regions

The draft final proposal also removed the possibility of forming climate regions that would enable reporting entities to share excess energy and the associated emissions. The climate region would effectively create a carve-out from the overall residual rate for the reporting entities that participate in the climate region. This carve-out would likely affect the ultimate residual rate because the carve-out would change the generation mix that composed the residual rate and the associated emissions. DMM agrees that the simplified approach without climate regions should be used until a clearer framework for forming climate regions is developed, and the potential impacts of climate regions on the overarching residual rate is studied in more detail.

Emissions calculations

DMM agrees with the ISO’s decision to require the registration of emissions factors for reporting entity resources in Master File in accordance with the rules relevant to their regulatory environment. This is in contrast to past proposals, which contemplated a separate emissions reporting process that would allow reporting entities to avoid coordination problems associated with working with scheduling coordinators. The primary benefit of using Master File is that it is covered by the ISO’s existing tariff requirements and rules regarding confidentiality and accuracy.

The ISO also altered the proposed accounting approach for charging load of energy storage resources owned by reporting entities that do not have other load. Previously, the ISO proposed to account for energy storage resources’ charging as a load adjustment. However, this accounting method did not consider that some reporting entities, such as independent power producers, may own storage resources but do not have other load. For such resources, the new method would assign emissions to storage charging based on the energy that serves them:

• Standalone storage resources are only assigned the residual rate
• Hybrid resources are assigned the emissions rate associated with the non-storage components
• Co-located storage resources are treated as hybrid resources when the off-grid charge indicator is enabled, and assigned the residual rate when it is not

DMM agrees that modeling emissions for storage charging by reporting entities without other load is reasonable and accurately represents the likely emissions associated with those entities.

[1] GHG Coordination Working Group meeting materials: https://stakeholdercenter.caiso.com/StakeholderInitiatives/Greenhouse-gas-coordination-working-group  

[2] Greenhouse Gas: Accounting and Reporting Draft Final Proposal, California ISO, July 18, 2025: https://stakeholdercenter.caiso.com/InitiativeDocuments/Greenhouse-Gas-Coordination-Accounting-and-Reporting-Draft-Final-Proposal.pdf

[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

[4] Reporting entities are entities that participate in CAISO markets that choose to use the accounting and reporting approach and associated reports.

[5] Null power refers to generation without renewable energy certificates (RECs)

2. Does your organization plan to use the public report data?

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. Does your organization plan to request the private report data?

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. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final 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.

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

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 calculations for various fuel types.

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

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

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.

8. Please provide the ISO with any additional feedback not already covered.

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. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

Please see the PDF attached for CRS's complete set of comments.

2. Does your organization plan to use the public report data?

Please see the PDF attached for CRS's complete set of comments.

3. Does your organization plan to request the private report data?

Please see the PDF attached for CRS's complete set of comments.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

NA

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

Please see the PDF attached for CRS's complete set of comments.

6. Please provide your organization’s feedback on the calculations for various fuel types.

Please see the PDF attached for CRS's complete set of comments.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

Please see the PDF attached for CRS's complete set of comments.

8. Please provide the ISO with any additional feedback not already covered.

Please see the PDF attached for CRS's complete set of comments.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

N/A

2. Does your organization plan to use the public report data?

N/A

3. Does your organization plan to request the private report data?

N/A

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

N/A

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

As NV Energy stated in previous comments, NV Energy still holds the position that the initial GHG emissions accounting and reporting approach should adopt a simplified single approach rather than multiple reporting options. NV Energy believes that allowing entities the option to select which resources will be designated as Excess Energy may not accurately reflect the true emissions rate throughout the market footprint. Furthermore, a simplified single approach during the initial issuance of the report would provide a baseline for further refinement. Once the EDAM market is implemented, market participants will have more data and market experience to better understand the value of each reporting mechanism.  

NV Energy is still opposed to assigning generation from renewable resources to Null Power. The draft final proposal still includes Null Power and the ability to assign 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 Renewable Portfolio Standard (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.

NV Energy acknowledges the comments made by the California Air Resources Board (CARB) to exclude Renewable Energy Credits (REC) accounting. Specifically, CARB recommends, “CAISO limit the scope of its proposal to GHG accounting and exclude REC accounting, as these are separate and distinct accounting approaches.”¹ RECs account for one megawatt-hour generated from a renewable resource to meet RPS metrics rather than the physical emission of a GHG from a resource. Assigning an emissions rate to generation from renewable energy resources as a result of Null Power could overstate the actual emissions of the market.

¹ California Independent System Operator. (2025, July 3). CAISO GHG Issue Paper – CARB Comment Letter. https://stakeholdercenter.caiso.com/InitiativeDocuments/CAISO-GHG-Issue-Paper-CARB-Comment-Letter-July2025-signed.pdf

6. Please provide your organization’s feedback on the calculations for various fuel types.

N/A

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

N/A

8. Please provide the ISO with any additional feedback not already covered.

N/A

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

Yes

2. Does your organization plan to use the public report data?

Once available, Oregon Department of Environmental Quality (DEQ) intends to evaluate the publicly reported data to determine its usefulness in informing the assignment of emissions to purchases from centralized markets under the state’s Greenhouse Gas Reporting Program.  

3. Does your organization plan to request the private report data?

Oregon DEQ plans to request access to the private data to further assess and compare with the public data produced by CAISO. The intent is to better understand how this information compares to the public report and to further inform the agency on the data options available for assigning emissions to purchases from centralized markets under the state’s Greenhouse Gas Reporting Program.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

Excess energy options: Oregon appreciates the inclusion of multiple options for the treatment of excess energy and the flexibility to accommodate state regulatory methodologies, allowing states to determine the appropriate treatment of excess energy based on their specific needs.

Null power: The definition of null power requires further clarification. As currently proposed, it appears to include generation that is not necessarily associated with Renewable Energy Certificates (RECs), while potentially excluding power that does generate RECs under certain programs. It may be more appropriate to defer to individual states to determine what constitutes null power and when it must be reported as such to centralized markets.

Emissions factors: It would be helpful if the final proposal, or a future implementation phase, includes more specificity related to emissions accounting. This could include identifying the pollutants being reported, specifying the units of measurement, and detailing the methodology used to quantify emissions. For example, will emissions be reported in metric tons of carbon dioxide equivalent (CO2e), or broken out by individual greenhouse gases such as CO2, CH4, and N2O? Additionally, clarification on which Global Warming Potentials (GWPs) will be used for emissions quantification would be valuable, as well as whether these parameters can be tailored in the private reports to meet state requirements. 

6. Please provide your organization’s feedback on the calculations for various fuel types.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

The final draft elements appear to allow Oregon to utilize the data as intended, while also preserving other states' ability to separate null power in accordance with their own program needs. 

8. Please provide the ISO with any additional feedback not already covered.

Oregon appreciates CAISO’s consideration of state specific needs and proposing solutions that allow for flexibility.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

PacifiCorp supports with caveats the directionality of the Draft Final Proposal for the Accounting and Reporting approach. PacifiCorp believes that the publication of the report without the optionality would allow stakeholders and regulators the ability to see the most accurate emissions profile of the market. Additionally, without regulations fully developed for how to account transactions in organized markets, it would be prudent to shape policy once the real-world data is attained. Notwithstanding, PacifiCorp does not believe that null power should be included within emissions reporting. 

2. Does your organization plan to use the public report data?

Initially, PacifiCorp intends to use the public report data to better understand the residual mix of the market. PacifiCorp strongly believes that the static unspecified emissions factors, whether they are 0.428 MT CO2e/MWh or 0.437 MT CO2e/MWh, and the state rules and regulations that require them should be updated to allow more accurate unspecified emissions reporting. PacifiCorp seeks to work with regulators and stakeholders to change unspecified emissions reporting and allow unspecified imports from a centralized electricity markets to utilize an emissions factor that changes annually based on data from a public or private report. This process will take time and will be correctly subject to input from many stakeholders and may take months or years to implement.  

3. Does your organization plan to request the private report data?

PacifiCorp supports with caveats as it has not yet seen the contents of the private report.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

?No comment. 

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

As previously commented on, PacifiCorp believes it would be beneficial to see the outcome of the market emissions without the optionality the excess energy option gives. PacifiCorp understands the individual reporting needs of market participants, however, organized market reporting from regulators is still in development and the ability to view the emissions profile of the residual market rate, without the optionality, would provide stakeholders with a more accurate look at what is serving the reporting entities load. The current average emissions rate report produced by the CAISO shows the emissions of the entire WEIM footprint to be less than the current unspecified rate of 0.428 MT CO2e/MWh. PacifiCorp appreciates that the public report will show the selection of the market participants for tracking of how this optionality affects the residual rate. 

PacifiCorp also continues to oppose the inclusion of null power, even on a voluntary reporting basis. Null power is relevant in renewable energy credit (REC) compliance reporting, but this Straw Proposal is solely dealing with emissions. The inclusion of null power will likely only lead to more confusion from regulators and increases the likelihood of omitted or double-counted emissions. This position of excluding REC accounting is supported by many other Working Group participants as well as the California Air Resources Board in their July 3, 2025, issue paper.  

6. Please provide your organization’s feedback on the calculations for various fuel types.

?No comment. 

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

?No comment. 

8. Please provide the ISO with any additional feedback not already covered.

PacifiCorp would like confirmation on the following: 

• Whether the new field for emission factor in the Masterfile will be in MTCO2e/MWh 

• Will the CAISO host the data for registration? If so, do EDAM entities need to add load information? If not, how will coordination be done with the vendor and CAISO for their quarterly reports.  

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

PGE thanks the CAISO for leading this initiative to enhance the accounting and reporting for emissions. PGE directionally supports the draft final proposal but would like to see targeted refinements to the final design and reassess based on the data provided at implementation. The outcome should reflect the CAISO's commitment to policy neutrality across the various jurisdictions of regional market participants.

PGE has long supported the initiative’s primary objective of developing an emissions tracking report across CAISO markets. As stated in the CAISO’s issue paper on GHG accounting and reporting, “a key objective of the Accounting and Reporting approach is to standardize emissions tracking to allow an entity, such as a market participant, to track progress towards its climate goals over time. This means associating the market dispatch with the entity’s owned and contracted resources based on the market footprint the entity operates in. It also enables, to the extent practicable, attribution and assignment of energy from specific resources and associated emissions to states and/or individual market participants (e.g., BAAs, SCs, LSEs).”

However, PGE remains concerned that the Accounting & Reporting approach has deviated from its initial core objective of emissions reporting by focusing instead on null power and renewable energy certificates (REC) accounting. In so doing, the approach violates the commitment to policy neutrality, as RECs have no role to play in emissions reporting in a state like Oregon. RECs are an inaccurate and imperfect tool for measuring GHG emissions. The proposal to remove null power volume from the emissions factor will distort accurate representation of physical emissions on the grid at any given interval. RECs do not equate to greenhouse gas emissions. The definition of REC and REC eligibility can vary state to state as defined in each state’s statutes.  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 would undermine the accuracy and comparability of REC Accounting in a given state. REC accounting is  separate and distinct from GHG emissions reporting.  This further highlights the differences of REC accounting compared to emissions accounting. See our response in Question #5 for additional information. 

PGE recommends that the Accounting and Reporting approach accommodate each state’s regulations and jurisdiction. Null power treatment should therefore be optional based on respective entity’s jurisdictional rules. Furthermore, generation resources should not automatically default as null power.  PGE recommends that the data provided is accurate with sufficient information that allow the respective state regulatory agencies to determine how to treat null power and emissions accounting.

2. Does your organization plan to use the public report data?

As commented in Question #1 and #5, the proposed treatment of null power and REC accounting requirement is still a concern for PGE. In light of WA CETA’s request for null power requirement while maintaining policy-neutrality across western states, PGE proposes that null power reporting be optional and provided in a format that allows the respective state regulatory agencies to determine how to treat null power.

3. Does your organization plan to request the private report data?

PGE does not see a need for a private report at this time. Pending future rulemaking and approval in Oregon, PGE believes a public report is sufficient as long as the data is accurate and the data for null power is provided in a format that allows the respective state regulatory agencies to determine how to treat null power.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

As previously commented, PGE opposes null power reporting for purposes related to GHG accounting. Universal null treatment is not consistent with Oregon law or the Oregon Department of Environmental Quality (DEQ) emissions reporting rule requirements that date from 2009. House Bill 2021(2021), codified in Oregon law, requires the consideration and reporting of the emissions of the underlying generating resource, not its attributes. In Oregon, emissions reporting and REC accounting are separate and distinct regulatory and accounting requirements.

This perspective is also shared by California Air Resources Board (CARB), who also submitted comments opposing the conflation of RECs and emissions in GHG accounting: “CARB recommends that CAISO limit the scope of its proposal to GHG accounting and exclude REC accounting, as these are separate and distinct accounting approaches.”[1]

PGE believes that null power treatment should remain a reporting entity’s decision based on applicable jurisdictional regulatory policy. If null power accounting is implemented:

1. Null power reporting should not be required as currently proposed. Instead, it may be optional to allow entities to flag null power.
2. An entity reporting null power would need to flag the resource accordingly. PGE opposes the CRS design requiring all WREGIS-registered MW default to null power unless the reporting entity flags the REC’s transaction or retirement. PGE believes that requiring the default assumption of null power for any WREGIS-registered resource interferes with the stated objective of maintaining regional policy neutrality.
3. Because definitions of REC eligibility (and, by extension, null power) vary across states, PGE requests clarification on how the CAISO will ensure that its reporting framework remains neutral to differing state policies. For instance, it is unclear how the CAISO would treat a transaction in which a REC is valid in one jurisdiction but not another, even though the associated MWh has been sold.
4. PGE seeks more information for how the CAISO plans to implement optional null power reporting.  For entities subject to null power reporting, (1) how will renewable resources that are dispatched but not yet registered or approved for WREGIS yet and (2) what happens when there is a change in null power designation subsequent to CAISO’s report?

In addition, depending on what is meant by the collection of ownership and contract information, there may be information that PGE or other companies would find confidential either as a business practice or pursuant to a contract with a counterparty. CAISO must provide methods to ensure that the confidentiality of such information is retained, and if potentially subject to public records request, has safeguards in place for ensuring that the data is appropriately redacted or otherwise protected.

[1] https://stakeholdercenter.caiso.com/InitiativeDocuments/CAISO-GHG-Issue-Paper-CARB-Comment-Letter-July2025-signed.pdf

6. Please provide your organization’s feedback on the calculations for various fuel types.

PGE supports the proposed options for reporting emissions factors. PGE looks forward to gaining more information on the updated Business Practice Update for Master File inclusion of emissions factor.

For the calculation of fuel type, PGE recommends including all technology types and its treatment. The current resources listed do not include technology types, such as nuclear or geothermal.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

As referenced above, PGE desires an emissions accounting report reflecting the emissions rate of the residual market, regardless of null power.  Absent this option given WA CETA requirements, PGE recommends that there be sufficient data to allow each jurisdiction flexibility in null power treatment as recommended by the Oregon state agencies.

8. Please provide the ISO with any additional feedback not already covered.

PGE requests that the CAISO provide future opportunities to revisit policy design and methodology during IT implementation and after IT implementation when the data is available. This is in reference to policy questions and decisions that may need to be revisited later based on IT implementation considerations, such as for confirmation of contracts for shared resources.

As noted in prior comments and subsequently discussed in the GHG regulatory subgroup, PGE appreciates the CAISO for including the additional allocation method for jointly shared resources. This method would be based on each entity’s bid award and its share of metered performance to allocate MW and emissions accordingly. The MW and emissions assignment policy design for shared resources may also be impacted based on whether the other party joins a different organized market. PGE looks forward to understanding the implementation and data once available to reassess allocation of MW and emissions for shared resources.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

Support with caveats.

2. Does your organization plan to use the public report data?

Yes, PGP is likely to use the public report data for informational purposes and to inform policy positions on future GHG topics.

3. Does your organization plan to request the private report data?

PGP itself will not request private report data; however, PGP members who are market participants are likely to participate in the accounting and reporting approach and request the private report data. At this time, doing so is not required by state regulators or agencies but it is possible this will change over time.  

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

In general, PGP supports the Draft Final Proposal and appreciates the process the CAISO used, including the working group and sub-group coordination, to solicit and incorporate feedback from stakeholders. Further, PGP generally supports the increased transparency the reporting approach will engender and looks forward to the availability of greenhouse gas (GHG) emissions reporting that aligns with contractual obligations and other emissions reporting requirements.

PGP does have some concern with one aspect of the final proposal’s approach to null power. PGP’s understanding is that under the final proposal, each reporting entity will be able to determine whether or nor the residual rate added to its report when its load exceeds the generation of its resources is inclusive of null power or not. If an entity opts to include null power in its residual mix, incorporating the emissions profile and fuel type of the null power, it appears that this will be used for state reporting purposes. Even though this election is provided through a private report, if the underlying fuel type and emissions profile are used for state reporting purposes, PGP is concerned that Washington’s policies on double-counting could render any associated RECs unusable for compliance with Washington’s Clean Energy Transformation Act (CETA).

PGP understands the interest in remaining neutral across different state policies and program types and appreciates the lengths that CAISO has undergone to accommodate REC-based accounting and programs that do not make adjustments for RECs. Nonetheless, the practical outcome of enabling the use of the underlying fuel type and emissions profile of null power in any residual mix calculations is that it creates a risk for the owner of the associated REC that the underlying non-power attributes will be considered to have been double counted. The owner of the REC is likely to take measures to avoid this outcome – this could include by self-scheduling, not participating in the accounting and reporting program, or other market behavior that would avoid contributing excess energy to the residual rate. This in turn could impact market outcomes and efficient optimization. Accordingly, PGP’s preference continues to be that hourly emissions values associated with null power not be published in the public report nor used for the calculation of residual mix in private reports.

6. Please provide your organization’s feedback on the calculations for various fuel types.

No comment at this time.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

No comment at this time.

8. Please provide the ISO with any additional feedback not already covered.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

SMUD supports with caveats the Draft Final Proposal of the Greenhouse Gas Accounting and Reporting Approach. SMUD requests the CAISO reconsider the potential requirement of null power reporting for entities. SMUD understands the complexities of creating policies that reflect the unique perspectives of all stakeholders, including external CAISO stakeholders. However, SMUD strongly believes this portion of the proposal does not result in accurate emissions accounting. In California, RECs are used for RPS accounting, which is independent of, and significantly differs from, accounting for an emissions profile. An accurate emissions profile can be determined without requiring entities to report power in a resource portfolio that lacks an associated REC. SMUD encourages the CAISO to remove the accounting of null power from the Draft Final Proposal or amend the proposal to no longer require it, regardless of implementation capabilities.

2. Does your organization plan to use the public report data?

Support with caveats – SMUD is generally in support of the GHG Accounting and Reporting proposal caveated with the position in #1. Preliminarily, SMUD anticipates having use for the public reporting data.

3. Does your organization plan to request the private report data?

No position – SMUD sees potential value in the private report data but has not yet determined when or if it may request it. 

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

N/A

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

SMUD recognizes that other entities out of state may have different policies and requirements and is not opposed to the CAISO providing options to address those different needs. However, the CAISO should not impose requirements on any entity to incorporate policies that do not apply to them and ensure appropriate emissions rates are used in the overall system and residual power mix methodologies.

SMUD opposes any requirement or the deferral of a decision on any requirement that would obligate reporting entities to report null power. The working group has discussed at great length that regulators in different states (and even within the same state) differ on whether null power is relevant to GHG accounting. As stated above, in California, RECs and RPS accounting differ significantly from emission accounting and should not be considered as a part of this emission accounting methodology.

SMUD understands CAISO’s desire to adopt a uniform approach but as many other stakeholders have expressed, this is a state policy issue and null power is not needed to determine an accurate emissions profile. Consequently, it is inappropriate for CAISO to impose such a requirement unless all western states are aligned on null power accounting methodologies and CAISO has the information necessary to decide the issue now, without delaying until implementation.

6. Please provide your organization’s feedback on the calculations for various fuel types.

 No response at this time.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

No response at this time.

8. Please provide the ISO with any additional feedback not already covered.

  No response at this time.

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

Western Resource Advocates (WRA) appreciates the opportunity to provide feedback on the Draft Final Proposal and commends the work of CAISO and stakeholders in developing this proposal. WRA generally supports pursuing this proposal while recognizing the areas where further development and decision-making are indicated. It is essential to continue to enhance the accuracy of GHG accounting in the transition to day-ahead markets in the West. It also remains vital to explore options to best support the compliance needs of states with non-pricing GHG emission reduction regulations.

2. Does your organization plan to use the public report data?

WRA supports and will use public GHG reporting.

3. Does your organization plan to request the private report data?

WRA will not request from CAISO any data that is confidential to a reporting entity.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

Not applicable, but WRA encourages CAISO and state regulators in states with non-pricing emission reduction targets (e.g. New Mexico, Nevada, and Colorado) to continue to coordinate regarding state needs.

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

Excess energy methodology. The User Choice option presents concerns regarding accuracy and transparency. WRA recognizes the cited needs in various states to maintain flexibility in selecting an excess energy methodology. If this accommodation is necessary, further safeguards to maximize accuracy should be discussed.

Null power. The proposed required reporting approach appears well-suited to encompass differences in state REC policies under a consistent policy without mandating changes to differing state REC requirements. WRA also supports continued exploration of the CRS proposal for default null power designations for WREGIS-registered generation to mitigate double-counting.

6. Please provide your organization’s feedback on the calculations for various fuel types.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

8. Please provide the ISO with any additional feedback not already covered.

WRA encourages ongoing coordination between CAISO and EDAM stakeholders with other markets operating or entering the West to address seams. This includes exploring mechanisms to mitigate inconsistencies in GHG design and accounting that may result in inaccuracies or inefficiencies. Market operators, state regulators, and stakeholders should also explore options for centralized West-wide emissions tracking, including alignment with REC tracking mechanisms.

WRA also supplies the attached "Enhancing Greenhouse Gas Accounting and Dispatch Support in the CAISO and SPP Markets+" report prepared by Brattle for WRA and Interwest Energy Alliance. The report includes key recommendations for Western market GHG enhancement, including:

1. Expanding reporting support for physical system emissions data (marginal, average, and location-based consumption rates) on a time-granular and locationally granular basis.
2. Providing robust allocation GHG tracking and reporting data, including an accurate residual rate, with essential GHG data categories for each entity; comprehensive and complete data; granular accounting; self-consistency between REC markets, self-supply claims, in-market dispatch, and GHG reporting; and a focus on time and locational accuracy in the residual emissions mix.
3. Enhancing in-market dispatch support for GHG-pricing and non-pricing states, via options such as: aligning qualification requirements for attributable non-emitting MW with exclusive clean energy claims and REC-based accounting, applying the in-market-calculated residual mix for any unspecified market purchases, expanding the use of in-market attribution of MW to apply to both GHG-pricing and non-pricing states, and enhancing representation of transmission system limitations to limit the maximum quantity of market-attributed MW supply.      

1. Does your organization directionally support the Draft Final Proposal for the Accounting and Reporting approach?

WPTF generally supports adoption of the proposed GHG Accounting approach. However, we have significant concerns regarding the proposal to designate all megawatt-hours (MWh) of dispatched energy from resources registered in the Western Renewable Energy Generation Information System (WREGIS) as "null power." This mandatory designation of null power without the explicit direction of a reporting entity is inappropriate and should be eliminated. We address this issue in our response to question 8 below.

2. Does your organization plan to use the public report data?

Yes. We anticipate that the public data report will be of interest to many entities and organizations that are not market participants.

3. Does your organization plan to request the private report data?

No, as WPTF is not a market participant.

4. If your organization is a state agency, are there areas of the proposal where you would like to see more state deference to in the final proposal?

5. Please provide your organization’s feedback on the reporting registration policy items including: collection of ownership and contract information, excess energy option, null power, emission factors, or any other relevant topics related to registration.

No comment.

6. Please provide your organization’s feedback on the calculations for various fuel types.

No comment.

7. Please provide your organization’s feedback on the public report data elements, as reflected in this Draft Final Proposal and the excel workbook.

CAISO should further clarify in both the public and private data reports when null power and unconfirmed MWs is a subset of the MW of residual generation, and when it is entirely separate from the MWs of residual.

8. Please provide the ISO with any additional feedback not already covered.

The mandatory designation of null power is fundamentally incompatible with the stated objective of accurately assigning energy and associated emissions. WPTF believes that the fundamental purpose of the accounting framework is to enable accurate and transparent accounting of GHG emissions associated with serving a market participant’s electricity load based on hourly delivery of electricity. The framework is not intended to support annual or multiyear accounting of renewable energy procurement. Entities with clean energy mandates or goals based on procurement of renewable energy, rather than physical delivery of electricity, already have a mechanism for tracking this procurement outside of the market: retirement of renewable energy credits (RECs).

Advocates of REC-style accounting, including the Washington Utilities and Transportation Commission, believe that RECs contain all possible attributes associated with the underlying generation resource and energy, including the actual emission rate of the resources. These entities argue that when a market participant’s procured renewable energy, as determined by retained RECs, is in excess of load, emissions should be associated with this excess when adding it to the residual market energy. These imputed emissions are completely imaginary, as they are not associated with actual generation in the market.  Multi-year REC-style procurement programs do not align with hourly dispatch and delivery of energy, and in the case of Washington, the MW allocated to utilities based on RECs will not match the MW attributed to the state by the market under the GHG pricing program.

Other market participants and regulators, including the California Air Resources Board, the Oregon Department of Environmental Quality and the Washington Department of Ecology, consider the actual, direct emission rate of a resource to convey with the underlying electricity, and view any imputation of imaginary emissions to ‘null power’ as fundamentally incompatible with the goal of accurate GHG accounting.

The CAISO, to its credit, has attempted to find a way to accommodate both these views. The proposal to publish the residual data set on an hourly basis with null power volumes, but not fuel types of the null power MW, and without the publication of an hourly residual emission factor represents an appropriate compromise that was acceptable to all market participants and state regulators.

However, in the draft final proposal, CAISO now proposed to go beyond this carefully crafted compromise and make designation of null power mandatory. Although this is not suggested in the CAISO’s draft final proposal, it is clear from the history of discussions within the working group and the proposals by CRS, the underlying goal of designating power as ‘null’ power would be to prevent the direct emission rate of the resource that produced the electricity to be used for GHG accounting in any way – not in the calculation of a residual market emission factor, and not as a specified emission factor under a GHG pricing program or GHG non-pricing program such as Oregon’s HB2021. Such an outcome is completely antithetical to the objective of GHG emission accuracy.

The mandatory designation of null power expands the concept of null power beyond that intended by regulators and market participants that use REC procurement accounting and imposes a policy on all market participants. While the concept of null power broadly refers to energy that is transacted without renewable energy credits, within the GHG Accounting Framework it is inseparable from the concept of excess energy. That is, reporting entities need the ability to retain any RECs associated with excess energy and designate the equivalent portion of excess energy as ‘null power’ so that those RECs can be used for compliance with RPS style clean energy standards or goals. WPTF supports this general concept, as we believe that it is the buyer of the REC that appropriately should be able to make the determination of whether the excess energy is null or not (subject to any applicable regulatory requirements).

The CAISO proposal to make all energy dispatched by WREGIS-registered resources takes that decision out of the buying entity’s and state regulator’s hands, and instead imposes a unilateral determination that all energy from a WREGIS-registered resource is null power. This is a policy decision that is inappropriate for CAISO to make. It is also completely unnecessary given the ability of reporting entities to designate their excess MWs as null power. 

The mandatory designation of null power is unfair to independent power producers that own WREGIS-registered resources. Part of the CAISO’s justification for the mandatory designation of null power is that a reporting entity can override the designation. However, much of the generation from IPP-owned WREGIS-registered resources may be sold to counterparties who are not reporting entities. With the exception of IPP’s that own and operate storage resources, it is our understanding the IPPs cannot register as reporting entities as they do not serve load. Thus, unless the IPP’s counterparty is a reporting entity, an IPP will have no means to override the designation of null power for MWs from its WREGIS-registered resources. This would undermine the ability of those IPPs to comply with contractual requirements with different counterparties.

It is not clear how the mandatory designation of null power will interact with specified source resource attribution into the GHG Pricing areas. As noted above, the stakeholders who are most concerned about null power clearly wish to ensure that power designated as null cannot be attributed or reported as a specified import into a GHG pricing programs. Given that it does not currently seem likely any California load-serving entities will elect to be reporting entities for GHG Accounting, it is not at all clear how the mandatory designation of energy as null from WREGIS-regulated resources will impact the ability of IPPs to offer this energy as specified into California and receive a market attribution. Does CAISO intend to prevent this energy from being attributed to California by virtue of the fact that it has been designated as null power within the GHG accounting? If so, this would conflict with the cap-and-trade program rules. If not, it would underscore the absurdity of mixing REC style accounting with GHG emissions accounting and attribution.

CAISO should eliminate the mandatory designation of null power. Given these concerns, we strongly urge CAISO to eliminate the mandatory designation of null power from the adopted GHG Accounting approach. If CAISO chooses to retain the mandatory designation, then it should provide a simple means for IPPs to override the designation without being a reporting entity. CAISO should also clearly state that any null power that is not associated with a reporting entity’s excess energy may be offered and attributed into the GHG pricing areas.