Comments on Large Loads Draft Tariff Language

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Please see attachment.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Please find attached the BAMx redlines to the Large Loads Enhancements draft tariff language.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

The California Community Choice Association (CalCCA) appreciates the opportunity to comment on the Large Loads Enhancements draft tariff language. CalCCA’s recommended redlines acknowledge that there is the need to identify additional data related to large load operations, but provide the CAISO’s proposed implementation working group the opportunity to further develop these requirements with sufficient input from required stakeholders. CalCCA’s comments on the Draft Final Proposal identify the reasons why additional time and process is required before adopting comprehensive requirements for data reporting from the SC to the CAISO.  

25.7.3   Load Serving Entity Scheduling Coordinator Requirements Large Load Operational Requirements

Day-ahead forecasts, hourly forecasts, operational status, real-time consumption in accordance with the CAISO’s standards for direct telemetry and consistent with the requirement for telemetry set forth in Section 7.6.1, and other operational data the CAISO requires to maintain sufficient operational visibility must be provided to the CAISO for each Large Load. The entity responsible for providing each category of data, the applicable data exchange requirements and communication protocols, and any additional data requirements will be as specified in the applicable Business Practice Manual.

The SC representing the Load Serving Entity’s service area for the Large Load will include the Large Load in its Bids, Scheduled Demand, and Meter Data, as applicable, for that area. The Scheduling Coordinator also must provide the CAISO the following, specific to each Large Load it represents:

1. Daily and hourly forecast data otherwise required for the CAISO Forecast of CAISO Demand;
2. Any real-time, material change from provided forecasts, including changes resulting from energization activities, material operational changes, curtailments, Outages, derates, operating limits, operating envelopes, or co-located generation impacts that materially affect expected Demand;
3. Planned Outages, forced Outages, derates, and other operating conditions that materially affect the Large Load’s expected consumption or operating capability; and
4. Operational status and real-time consumption to the CAISO in accordance with the CAISO’s standards for direct telemetry and consistent with the requirement for telemetry set forth in Section 7.6.1

25.7.3.1            Load Serving Entity Scheduling Coordinator Requirements

The Scheduling Coordinator representing the Load Serving Entity’s service area for the Large Load will include the Large Load in its Bids, Scheduled Demand, and Meter Data, as applicable, for that area.

25.7.3.1 2         Large Load Scheduling Coordinator Requirements

If permitted by the Local Regulatory Authority to be its own Load Serving Entity, a Non-Generator Resource, or a Participating Load, the Large Load may elect to comply with the requirements of Section 25.7.3 and participate in the CAISO Markets through its own Scheduling Coordinator in lieu of the service area Load Serving Entity Scheduling Coordinator. A Large Load participating as a Proxy Demand Resource or Reliability Demand Response Resource will have the service area Load Serving Entity Scheduling Coordinator comply with Section 25.7.3 and submit Scheduled Demand including the Large Load, but may have the Demand Response Provider or other Scheduling Coordinator comply with Section 4.13.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

CDWR-SWP opposes CAISO’s definition of Large Load because it does not specify that the definition applies only to new large load interconnections. CDWR-SWP asks CAISO to adopt the following definition instead:

Large Load – A new End User located at a single site whose Point of Interconnection is to the CAISO Controlled Grid, and that has a peak load of 50 MW or greater.

 Adopting this revised definition would be consistent with the potential definition suggested by FERC’s Show Cause Order (at P 1 n.2) which limits the definition to “a new commercial or industrial customer…” and FERC’s stated intention not “to disrupt existing commercial arrangements, but rather to establish prospective reforms.” Order at P 5. It is also consistent with CAISO’s statements in the Draft Final Proposal. See, e.g. Proposal at 3 (“CAISO offers this proposal to establish new procedures for fast and reliable interconnection of new large loads.”).

Without this change, the proposed definition of Large Loads would appear to encompass existing End Users with significant loads located at a single site, including potentially CDWR-SWP. That would subject such existing End Users to significant new tariff obligations (such as those included in new tariff section 25.7.3) without any change to their existing operations and without any stakeholder review of the need for or feasibility of imposing those new tariff obligations on existing End Users. CDWR-SWP does not believe that this is CAISO’s intended outcome based on the Draft Final Proposal and CAISO’s previous comments that the Large Load definition only applies to new interconnections. If CAISO believes the proposed Large Load definition and tariff revisions cannot be read to apply to existing End Users, CDWR-SWP requests that CAISO explain in detail why that is the case. 

CDWR-SWP again requests clarification of whether large loads are retail or wholesale customers. In particular, Footnote 34 says a Participating Load Agreement isn’t required because it applies only to loads receiving wholesale service, “which are not relevant to this initiative at this time.” CDWR-SWP requested this clarification in its September 2 Comments, but CAISO did not provide any clarification. Instead, CAISO introduced additional uncertainty by including Draft Tariff Language that allows Large Loads to “participate in the CAISO Markets using any model where they are capable of complying with the CAISO Tariff requirements, including without limitation as…Participating Loads.”

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

CLECA offers the following revision to the Appendix A definition, with additions underlined:

Large Load – A new End User located at a single site whose Point of Interconnection is to the CAISO Controlled Grid at a voltage level greater than 69 kV, and that has a peak load of 50 MW or greater. Where load is added at a site at which an End User was receiving service before the effective date of these tariff revisions, only the incremental load is evaluated against the 50 MW threshold.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Constellation appreciates CAISO’s substantial progress in developing tariff provisions for Large Loads and co-located generation. The draft language establishes useful study, modification, metering, operational, and market-participation provisions.

Constellation recommends targeted revisions to ensure the tariff implements CAISO’s stated policy that co-location and continued wholesale market participation can coexist. The tariff should also clearly assign responsibilities where the Eligible Customer, Load Serving Entity, Utility Distribution Company, retail supplier, and Scheduling Coordinator are different entities.

A. Section 25.5.1: Post-COD Modifications

Section 25.5.1 creates a pathway for adding co-located Large Load after COD, but states that the modification will be denied if CAISO determines Section 25.1 applies. The provision does not explain the basis for that determination, distinguish between curable and disqualifying changes, or identify the alternative process available to the generator.

Constellation recommends the following redline:

Section 25.5.1

Prior to making any modification after the Generating Facility’s Commercial Operation Date, including the addition of a co-located Large Load, the Generating Unit owner must first request that the CAISO evaluate whether Section 25.1 would apply to the modification.

In response to the Generating Unit owner’s request, the CAISO, in coordination with the affected Participating TO, will evaluate the proposed modification. The CAISO may engage the services of the applicable Participating TO to assess the modification.

The CAISO will inform the Generating Unit owner in writing whether Section 25.1 would apply to the modification and therefore be denied and will provide the technical and tariff basis for that determination. If Section 25.1 applies, the CAISO will identify the applicable Interconnection Request, modification, study, or other tariff process through which the Generating Unit owner may proceed.

Cots incurred by the Participating TO and the CAISO, if any, shall be borne by the party making the request under Section 25.5, and such costs shall be included in any CAISO invoice for modification assessment activities.

B. Section 25.7.6: Continued Wholesale Participation

Draft Section 25.7.6 appropriately requires studies to reflect the net impact of co-located generation and load, preserves access to RIS rights and services, and provides for the combined configuration to be reflected in the GIA.

The draft should also state the central policy principle reflected in the DFP and the October 1 discussion: serving co-located load does not require a generator to leave the CAISO market.

Constellation recommends adding the following paragraph after the first paragraph of Section 25.7.6:

An existing or new Generating Unit may serve a co-located Large Load while retaining all or a portion of its Interconnection Service and continued participation in the CAISO Markets, to the extent supported by the applicable Interconnection Studies, the operating capabilities of the combined configuration, the GIA, and applicable CAISO Tariff requirements. Serving a co-located Large Load will not, by itself, establish an intent to terminate, or constitute an event to trigger termination of wholesale market participation or retirement of the Generating Unit.

The CAISO and Participating TO will evaluate the requested configuration based on the maximum injections and withdrawals, requested Interconnection Service Capacity, expected operation of the Generating Unit and Large Load, applicable control technologies, and any enforceable limitations on simultaneous wholesale injections and service to the Large Load.

This language would implement the study-based, project-specific approach Constellation requested in its Straw Proposal comments. Constellation asked CAISO to evaluate what the combined configuration can provide rather than impose a categorical choice between serving load and remaining in the wholesale market.

C. Retirement Scenario 3

The draft tariff does not expressly connect the co-location provisions to CAISO’s Retirement Scenario 3 policy outlined in CAISO’s interconnection service capacity and deliverability retention for non-operating generating facilities initiative. The DFP states that Scenario 3 applies when a Participating Generator intends to terminate wholesale market participation while continuing to generate to serve load.

Constellation requests CAISO add the following paragraph to Section 25.7.6:

Retirement Scenario 3 applies only where the Generating Unit owner notifies CAISO it intends to terminate the Generating Unit’s participation in the CAISO wholesale market while continuing to generate to serve load through an applicable retail program. A Generating Unit that retains wholesale market participation and continues to satisfy its applicable bidding, availability, dispatch, metering, telemetry, and operating obligations will not be considered retired solely because it also serves co-located load.

The addition or service of a co-located Large Load will not, standing alone, terminate or reduce the Generating Facility’s existing Interconnection Service or eligibility to participate in the CAISO Markets. Any resulting limitation will be based on the electrical, reliability, operational, or studied impacts of the proposed configuration and the applicable requirements of the CAISO Tariff, GIA, and Participating TO tariff.

This language would align the tariff with CAISO’s policy distinction and avoid uncertainty for existing generation considering co-location.

D. Qualifying Capacity, NQC, Deliverability, and Market Participation

At the October 1 meeting, CAISO stated that a generator meeting its must-offer obligations and responding to dispatch would not have QC or NQC affected solely because it also serves onsite load, subject to project-specific review.

Constellation does not request that CAISO revise substantive RA eligibility rules in this initiative. The tariff should nevertheless prevent co-location itself from being treated as an automatic loss of QC, NQC, deliverability, or market eligibility.

Constellation recommends adding the following language to Section 25.7.6:

This Section does not alter the Qualifying Capacity, Net Qualifying Capacity, Deliverability Status, or eligibility to provide Energy, Ancillary Services, or Resource Adequacy Capacity of a Generating Unit serving a co-located Large Load. Any such treatment will be determined under the otherwise applicable CAISO Tariff and Local Regulatory Authority requirements based on the Generating Unit’s retained Interconnection Service, Deliverability Status, availability, performance, and compliance with applicable market obligations.

Where a co-located Large Load can reduce consumption in a measurable and enforceable manner, the CAISO may account for the resulting generation capability available for wholesale market participation consistent with applicable market, metering, telemetry, scheduling, dispatch, and performance requirements.

E. Section 25.7.3: Third-Party Scheduling Coordinators

Draft Section 25.7.3 assigns the relevant obligations to the Scheduling Coordinator representing the LSE’s service area. Section 25.7.3.1 allows a Large Load to use its own Scheduling Coordinator only if it is permitted to be its own LSE, NGR, or Participating Load.

Those provisions may not clearly address existing direct-access arrangements or other lawful structures in which the retail supplier, LSE, UDC or MSS, Eligible Customer, and Scheduling Coordinator are different entities.

FERC’s order defines an Eligible Customer to include a power marketer and a retail customer taking unbundled transmission service under a state retail-access program. The order also notes that Scheduling Coordinators identify the Eligible Customers they represent.

Constellation recommends revising Section 25.7.3 as follows:

Section 25.7.3 Load Serving Entity and Scheduling Coordinator Requirements

The Scheduling Coordinator representing the Load Serving Entity’s service area for the Large Load**, or another Scheduling Coordinator authorized under the CAISO Tariff and applicable Local Regulatory Authority requirements to represent the Large Load or the Eligible Customer taking transmission service on behalf of the Large Load,** will include the Large Load in its Bids, Scheduled Demand, and Meter Data, as applicable, for that area.

The applicable Eligible Customer, Load Serving Entity, Utility Distribution Company, MSS Operator, retail supplier, Large Load, and Scheduling Coordinator may satisfy the requirements of this Section through coordinated arrangements that clearly assign each tariff obligation and avoid duplicative submissions. The applicable arrangement must identify the Scheduling Coordinator responsible for submitting Bids, Scheduled Demand, Meter Data, forecasts, and real-time operational updates for the Large Load.

The Scheduling Coordinator also must provide the CAISO the following, specific to each Large Load it represents:

• Daily and hourly forecast data otherwise required for the CAISO Forecast of CAISO Demand.
• Any real-time material change from provided forecasts.
• Planned Outages, forced Outages, derates, and other conditions materially affecting consumption or operating capability.
• Operational status and real-time consumption in accordance with CAISO telemetry standards.

This revision would assign responsibility without requiring the service-area LSE’s Scheduling Coordinator to perform every function where another authorized Scheduling Coordinator lawfully represents the load or Eligible Customer.

F. Section 25.7.3.1: Large Load Scheduling Coordinator Requirements

Constellation recommends replacing the first sentence with the following:

If permitted by the Local Regulatory Authority to be its own Load Serving Entity, a Non-Generator Resource, or a Participating Load, the Large Load may elect to comply with the requirements of Section 25.7.3 and participate in the CAISO Markets through its own Scheduling Coordinator in lieu of the service-area Load Serving Entity Scheduling Coordinator.

A Large Load or Eligible Customer also may use another Scheduling Coordinator authorized under the CAISO Tariff and applicable Local Regulatory Authority requirements to perform scheduling, forecasting, market participation, or other responsibilities for the Large Load, provided that the responsible parties clearly assign all obligations under Section 25.7.3 and avoid duplicate or inconsistent submissions.

A Large Load participating as a Proxy Demand Resource or Reliability Demand Response Resource will have the service-area Load Serving Entity Scheduling Coordinator comply with Section 25.7.3 and submit Scheduled Demand including the Large Load, but may have the Demand Response Provider or other Scheduling Coordinator comply with Section 4.13.

Constellation also recommends adding:

Nothing in Sections 25.7.3 or 25.7.3.1 modifies or restricts direct-access, community-choice, municipal, or other retail-service arrangements authorized by the applicable Local Regulatory Authority.

G. Add “Eligible Customer” to the Operative Large Load Provisions

The draft tariff rarely uses the term “Eligible Customer,” even though FERC framed the Section 206 proceeding around transmission service provided by Eligible Customers on behalf of Large Loads. This omission contributes to the ambiguity discussed at the October 1 meeting.

Constellation recommends adding the following language at the beginning of Section 25.7:

End Users, including Large Loads, interconnect to the CAISO Controlled Grid pursuant to Participating TO tariffs.

Transmission service on behalf of a Large Load will be taken by an Eligible Customer consistent with the CAISO Tariff and applicable Participating TO tariff. The Eligible Customer may be a different entity from the Large Load, Load Serving Entity, Utility Distribution Company, MSS Operator, retail supplier, or Scheduling Coordinator. The applicable agreements will identify the rights and responsibilities of each entity.

This would not determine retail-service rights. It would clarify the identity and role of the FERC-jurisdictional transmission customer.

H. Section 25.7.2: FILI

Draft Section 25.7.2 requires a FILI agreement describing the circumstances and mechanisms for temporary curtailment. It does not specify the minimum terms necessary to make those obligations predictable and enforceable.

Constellation recommends that at minimum, the pro forma agreement specifies the processes including applicable operating standards, responsible decision-makers, communication, and maximum authorized withdrawals. As such, we propose the following revision to the second paragraph:

Prior to the synchronization of the Large Load to the CAISO Controlled Grid, the CAISO, Participating TO, Eligible Customer taking transmission service on behalf of the Large Load, and Large Load will execute an agreement describing:

1. The circumstances in which CAISO or the Participating TO may temporarily curtail the Large Load.
2. The mechanism used to perform the curtailment.
3. The maximum withdrawal level and applicable operating range.
4. The transmission constraints, contingencies, or operating conditions supporting curtailment, to the extent they can be specified in advance.
5. Curtailment notification, response time, duration, restoration, testing, and verification requirements.
6. The respective responsibilities of CAISO, the Participating TO, Eligible Customer, Large Load, Load Serving Entity, and Scheduling Coordinator.
7. The treatment of the Large Load in scheduling, forecasting, telemetry, planning, and real-time operations.
8. The conditions for transition to firm service after completion of the applicable Network Upgrades or Interconnection Facilities.

I. Section 4.19: Market Participation

Draft Section 4.19 affirmatively recognizes that Large Loads may participate through existing CAISO market models.

Constellation recommends one clarifying addition:

Large Loads may participate in the CAISO Markets using any model where they are capable of complying with the CAISO Tariff requirements, including without limitation as Proxy Demand Resources, Reliability Demand Response Resources, Participating Loads, and Non-Generator Resources. A Large Load may participate through its own Scheduling Coordinator or another Scheduling Coordinator authorized to represent the Large Load or applicable Eligible Customer under the CAISO Tariff and Local Regulatory Authority requirements. Large Loads participating in the CAISO Markets are eligible for all rights and subject to all obligations of the CAISO Tariff under those participation models.

This revision would align Section 4.19 with the requested clarification to Sections 25.7.3 and 25.7.3.1.

J. Appendix A: Large Load Definition

Constellation generally supports the proposed 50 MW definition but recommends addressing phased and commonly operated facilities.

Proposed redline:

Large Load means an End User located at a single site whose Point of Interconnection is to the CAISO Controlled Grid, and that has a peak load of 50 MW or greater. For purposes of this definition, CAISO and the applicable Participating TO will consider commonly owned, commonly controlled, or operationally integrated loads at the same site that share a Point of Interconnection or Interconnection Facilities based on their combined peak load. Separate metering, phased development, or separate equipment will not alone determine whether facilities constitute separate Large Loads.

K. Appendix KK Section 3.1

Appendix KK Section 3.1 allows Interconnection Service Capacity below Generating Facility Capacity.

Constellation recommends adding:

For a Generating Facility serving a co-located Large Load, the requested Interconnection Service Capacity may reflect the maximum expected net injection onto the CAISO Controlled Grid, subject to Interconnection Studies, enforceable operating limitations, and control technologies established in the GIA. The Generating Facility serving co-located Large Load shall not lose its Interconnection Service rights on the sole ground that it is serving the co-located Large Load.

L. Appendix KK Section 6.7.2.9

The final sentence allows CAISO and the PTO to note a changed co-location configuration in the GIA without updating the study results. That could create ambiguity over which rights and operating assumptions are effective.

Constellation recommends revising the final sentence:

For any co-located load addition or removal pursuant to the Participating TO tariff, if the CAISO and Participating TO determine that the change is a Material Modification or otherwise cannot be reflected in the Generating Facility’s Interconnection Study results, the CAISO and Participating TO will note the change in the GIA, but without modifying the Interconnection Study results.

The CAISO and Participating TO will provide the Interconnection Customer a written explanation of the determination, identify the affected study assumptions and Interconnection Service rights, and identify any available restudy, modification, downsizing, or new Interconnection Request process. The GIA will distinguish between the studied Interconnection Service and any additional configuration information included solely for notice or operational coordination.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Persistence Analytics Group LLC’s comments are provided in the attached document, “PAG_CAISO_Large_Loads_Draft_Final_Proposal_Comments_2026-10-09.docx.”

PAG is not proposing line-by-line tariff redlines in this submission. These comments address the Large Loads Draft Final Proposal and focus narrowly on evidentiary maturity, evidentiary currency, flexible-load capability, material change, and revalidation.

The attachment contains PAG’s complete comments.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

LS Power appreciates the opportunity to comment on CAISO’s draft large load tariff language. LS Power is also submitting proposed tariff redlines.

The draft does not clearly address large loads interconnecting to a non-load-serving Participating Transmission Owner (PTO), or the role of an affected PTO whose facilities may be impacted by an interconnection to another PTO. CAISO should specify the respective responsibilities of the interconnecting PTO, any affected PTO, and the applicable load-serving PTO, Utility Distribution Company (UDC), and Load Serving Entity (LSE), including how they will coordinate.

The Flexible Interim Load Interconnection (FILI) provisions should identify the UDC’s role when a large load interconnects to a non-load-serving PTO. They should specify which entity directs, implements, and verifies required load reduction or disconnection, and require coordination with any affected PTO whose facilities are implicated.

The data required under Section 25.7.1 may be held by an LSE or UDC rather than the PTO responsible for submitting it. CAISO should specify who obtains, validates, submits, and updates each data element, including after energization. The language should also require LSEs and UDCs to provide the information a PTO needs in order to meet its obligations.

LS Power supports public posting of aggregate proposed large load additions, planned network upgrades, and upgrade cost estimates. The draft places this information in the Transmission Plan. As CAISO moves to a biennial transmission planning cycle, relying on the plan alone could leave up to two years between updates. CAISO should update the public information following monthly concurrence decisions and material changes to planned upgrades.

CAISO should provide clear criteria for determining which planned transmission additions or upgrades require review through the Transmission Planning Process and which receive monthly concurrence review. In particular, CAISO should clarify what constitutes “high operational risk or uncertainty based on NERC Reliability Standards” and “planned transmission additions or upgrades,” and specify how it will coordinate its review with the interconnecting PTO and any affected PTO.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

ModsSys LLC appreciates the opportunity to provide comments on the California ISO Large Loads Initiative, Draft Final Proposal, and associated draft tariff language.

ModsSys LLC is not proposing specific tracked changes to the draft tariff language at this time.  Rather, ModsSys offers the following comment for consideration in the Large Loads Initiative and in future related stakeholder efforts concerning management of large electrical loads.

As California evaluates how to integrate increasingly large electrical loads while maintaining reliability and managing infrastructure requirements, ModsSys encourages consideration of measureable load-side efficiency measures that reduce the underlying cooling demand of buildings, in addition to operational strategies that curtail, shift, or otherwise manage electrical load.

For many commercial and industrial facilities, including warehouses, manufacturing facilities, commercial buildings, and certain large load facilities such as data centers, a portion of cooling demand may be influenced by solar heat gain and outdoor thermal conditions affecting the building envelope and cooling equipment.

Passive thermal measures may provide a complementary approach by reducing heat gain before mechanical cooling is required.  Examples may include elevated roof shading, exterior thermal barriers, HVAC-equipment shading, and other approaches intended to reduce solar exposure or improve localized thermal conditions around heat-exposed building and cooling-system components.

ModsSys is field-testing an Environmental Thermal Envelope concept using passive exterior thermal barriers.  Preliminary residential-scale field measurements have demonstrated measurable reductions in shaded roof-surface temperatures and measurable changes in roof, attic, and localized thermal conditions.

These preliminary results have not yet been validated at commercial or large-load scale.  The magnitude of resulting electricity and peak-demand reduction is expected to depend on factors including building type, insulation, roof area, internal heat loads, climate, cooling-system configuration, and the porportion of cooling demand attributable to exterior heat gain.

The relevant research question is which building types and operating conditions convert measurable thermal-load reductions into meaningful reductions in cooling electricity consumption and coincident peak demand.

ModsSys encourages CAISO, where appropriate in future large-load, demand-flexibility, or related stakeholder efforts, to preserve pathways for evaluating technologies that can demonstrate measurable reductions in underlying electrical demand through energy efficiency.

Potential evaluation metrics could include:

• reduction in coincident peak kW during high-temperature periods;
• reduction in cooling-system electricity consumption;
• changes in HVAC or heat-rejection equipment runtime;
• measured changes in roof, attic, intake-air, or surrounding thermal conditions;
• persistence of load reduction across weather and operating conditions;
• cost per kW and kWh of verified reduction; and
• scalability and reliability at commercial and large-load facilitites

Passive efficiency would not replace the interconnection, operational flexibility, reliability, or cost-allocation mechanisms addressed in the current Large Loads Initiative.  Rather, where independently verified, it could complement those mechanisms by reducing a portion of the electrical demand that ultimately must be supplied or managed.

ModsSys also encourages a distinction between temporary load curtailment or shifting and reductions in underlying demand achieved through verified efficiency measures.  Both may have value, but they represent different approaches and should be evaluated using appropriate measurement and verification requirements.

ModsSys is pursuing additional independent engineering analysis and commercial-scale validation to determine the building types and configurations where this approach provides the greatest energy and peak-demand benefit.

Thank you for the opportunity to participate in the Large Loads stakeholder process.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Please seee attached redlines. 

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

• Section 24

PG&E generally supports the inclusion of Large Loads in the discussion of the Overview of the TPP, specifically mentioning both interconnections pursuant to the PTO interconnection processes and Large Load data as inputs to the TPP. Although such data presumably already fell within other subsections of Section 24.3.1, the specificity provides clarity.

PG&E objects to the wording of Section 24.19 and 24.19.1 because “transmission or upgrades for Large Loads” should ensure that it accounts for transmission or upgrades for Eligible Customers (UDCs and MSSs) on behalf of Large Loads.” The OSC at Paragraph 66 indicates that FERC expects the provision of data on CAISO’s website … regarding the cost for network upgrades needed to provide transmission service to Eligible Customers on behalf of large loads.” Similarly, the reference to “Large Loads with executed interconnection agreements,” should refer to Eligible Customers with executed agreements on behalf of Large Load.”

• Section 25 – Interconnecting Large Loads

The CAISO has modified Section 25.1.1 to require non-exporting generators interconnected under Local Regulatory Authority jurisdiction to “ensure the Generating Units have sufficient control technologies, tested and validated by the Participating TO, to ensure Energy cannot be injected onto the CAISO Controlled Grid.” This provision could be read as if the CAISO were imposing a new obligation, unrelated to Large Loads or the OSC, on PTOs, under which PTOs could be found to have violated the CAISO Tariff if a non-exporting generator’s control technologies fail and power is inadvertently injected onto the CAISO Controlled Grid. This provision is unreasonable and exceeds the CAISO’s authority. PG&E suggests that the provision read:

…The interconnecting Participating TO for any Generating Units subject to this exemption is expected to abide by the testing and validation requirements established by, and subject to the jurisdiction of, the Local Regulatory Authority, which testing and validation requirements are intended to ensure Energy cannot be injected onto the CAISO Controlled Grid.

In any case, the CAISO should clarify that it cannot and will not impose liability on PTOs in connection with CPUC Rule 21 obligations.

Section 25.7—“Large Load Interconnections” should be titled Eligible Customer for Large Load Interconnections.”[1] Similar, the text of Section 25.7 starts by stating:

End Users, including Large Loads, interconnect to the CAISO Controlled Grid pursuant to Participating TO tariffs. The CAISO will coordinate with the Participating TOs to account for Large Load interconnections to the CAISO Controlled Grid in all Interconnection Studies.

It should be modified as follows:

End Users, including Large Loads, Eligible Customers that provide retail transmission service to Large Loads, interconnect Large Loads to the CAISO Controlled Grid pursuant to Participating TO tariffs. The CAISO will coordinate with the Participating TOs to account for Eligible Customer’s Large Load interconnections to the CAISO Controlled Grid in all Interconnection Studies.

Section 25.7.1 also should refer to the Eligible Customer. For example, the first sentence should read: “Participating TOs will apprise the CAISO of Eligible Customer for Large Load interconnections…”

Further discussion is necessary with regard to how the division of obligations as between Participating TOs and Eligible Customers should be split, particularly if the Eligible Customer and Participating TO are different entities.

Section 25.7.2 suffers also from the inclusion of the term “Large Load,” without the Eligible Customer being mentioned. The Eligible Customer must be a party to the agreement described by the CAISO in this section as “an agreement describing the circumstances in which the CAISO or Participating TO may temporarily curtail the Large Load receiving FILI.” This section contemplates that prior “to the synchronization of the Large Load to the CAISO Controlled Grid, the CAISO, Participating TO, and Large Load will execute an agreement describing the circumstances in which the CAISO or Participating TO may temporarily curtail the Large Load receiving FILI, and the mechanism the CAISO or Participation TO will use to perform the curtailment.” Yet, the LLE Proposal makes no mention of such agreement, and it needs to include the Eligible Customer in any case. Additionally, the CAISO’s discussion of FILI should refer to the interconnection service as being non-firm.

Section 25.7.3 is confusing in that it refers to: “The Scheduling Coordinator representing the Load Serving Entity’s service area for the Large Load…” The Scheduling Coordinator for a Large Load may not have a “service area,” given that a service area typically refers to an area in which a state regulatory body has imposed an obligation to serve. It is very unclear, in particular, if CCAs have “service areas,” particularly when a retail customer can opt out of CCA service. Moreover, some Scheduling Coordinators may represent the few Direct Access customers left in the CAISO, and such Scheduling Coordinators have no service area. Thus, this section should simply apply to the Scheduling Coordinator responsible for scheduling the load of the Large Load retail customer.

Section 25.7.4 appears to be unnecessary; also the term “Interconnection Customer” is used in  error. An Interconnection Customer includes anyone who has merely submitted a resource interconnection application. The Section also is confusing in that the entities listed, other than the Large Load, already must abide by Good Utility Practice and the purpose and need for the Section is thus unclear given such existing requirements. If the CAISO seeks to bind a Large Load retail customer directly to a CAISO Tariff obligation, that obligation should be in the agreement described in Section 25.7.2, not in a provision that is repetitive when applied to the Interconnection Customer, Scheduling Coordinators, and Participating TOs.

Section 25.7.6 continues the trend of the CAISO forgetting about the Eligible Customer. It even assumes the (resource) Interconnection Customer will submit an application to the Participating TO, when it is the Eligible Customer taking transmission service for the Large Load who would make the request.

• Section 4

New Section 4.19 states that “Large Loads may participate in the CAISO Markets using any model where they are capable of complying with the CAISO Tariff requirements, including without limitation as Proxy Demand Resources, Reliability Demand Response Resources, Participating Loads, and Non-Generator Resources.” The entire provision is inappropriate because each model has applicability requirements and they do not and should not vary between Large Loads and other retail customers. There is nothing special about a Large Load and other retail load as with regards to participation in such models. Some such models may have minimum MW requirements, that a Large Load readily meets or surpasses, but that is not reason to specifically call out Large Loads in a new section. Large Loads simply are no more and no less eligible “to provide, without limitation limitation, Demand Response Energy, Curtailable Demand, Resource Adequacy Capacity, and Ancillary Services consistent with their participation model and subject to the requirements of the CAISO Tariff” than any retail customer. Moreover, the sentence is confusing in using the term “without limitation,” when a Local Regulatory Authority may well have imposed a limitation on retail customer participation models, if FERC has permitted the Local Regulatory Authority to do so. Likewise, participation in a Local Regulatory Authority program also could disqualify a Large Load from participating in some CAISO participation models.

• Appendix A

Interconnection Facilities. PG&E strongly opposes changing the definition of “Interconnection Facilities,” which includes both Interconnection Customer-owned and Participating TO-owned facilities connecting a generator to the CAISO Controlled Grid. Wholesale generators deliver energy over Interconnection Facilities to the CAISO Controlled Grid in interstate commerce subject to FERC jurisdiction. In contrast, the previously discussed “intervening facilities” between a Large Load’s facilities, and the CAISO Controlled Grid are not used for transmission in interstate commerce but function as high voltage distribution facilities. A definition that reflects the concept of “intervening facilities” should replace this modification.

Large Load. See supra, § 1.a.

Point of Interconnection. Because the CAISO’s amended definition relies on the Interconnection Facilities definition it also causes PG&E concern. Moreover, it should remain, as defined by the CAISO Tariff, as associated with generator interconnections. PG&E proposes that this definition be left unchanged. As discussed above, Point of Withdrawal can be used in the Large Load definition instead.

• Appendix KK

Section 2.4.4. (Section relates only to co located Large Load, as, it resides in Appendix KK.) This new section begins with the erroneous statement that “End Users, including Large Loads, interconnect to the CAISO Controlled Grid pursuant to Participating TO tariffs.” No End Users including Large Loads, interconnect to the CAISO Controlled Grid pursuant to the TO Tariffs. End-Use customers interconnect pursuant to retail tariffs under state or Local Regulatory Authority jurisdiction. Once again, the term “Large Load interconnection” is problematic given the lack of any mention of the Eligible Customer, an entity that also should be coordinated as to “intervening facilities.” Finally, the last sentence again assumes that TO Tariffs cover the interconnection of large loads, not Eligible Customers acting on behalf of large load.

[1] Again, PG&E does not oppose the use of a term other than “Eligible Customer,” given that term has multiple uses.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

PARS Energy appreciates the opportunity to provide comments on the Large Load draft Tariff.

Our specific comments are listed at the bottom of the attached draft tariff language

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Please see SCE's attached comments.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Consistent with SunZia Transmission's comments on Issue 5 of the CAISO's Final Draft Proposal, the proposed tariff changes to address Electrically Proximate Large Loads are attached.

1. Please provide your organization’s comments on the Large Loads Enhancements draft tariff language in tracked changes.

Please see attached redlines.