Comments on April 5, 2022 meeting discussion

Interconnection process enhancements 2021

Comment period
Apr 06, 11:00 am - Apr 19, 05:00 pm
Submitting organizations
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Submitted 04/19/2022, 03:26 pm

Submitted on behalf of


Caitlin Liotiris (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

There are a variety of ways that data transparency for interconnection queue and transmission information could be improved upon in order to help provide better information to developers, Load Serving Entities (LSEs), and other stakeholders. As CAISO has heard from stakeholders in the IPE initiative, the hope is that by continuing to make progress towards better data availability and transparency, there may less unviable interconnection queue requests going forward, as developers concentrate on the locations on the system that are best situated for development.

All efforts that CAISO can take to improve data transparency and accessibility will be appreciated. In these comments, ACP-California requests additional information from the TPD Allocation reports, and supports additional information or a new supplemental report to the Phase 1 study to illustrate where there is still TP Deliverability on the system. Additionally, we reiterate requests for improvements in the reporting of project tracking/status within the Transmission Development Forums.

First, with respect to the TPD Allocation reports, ACP-California supports item #9 on the data transparency matrix, which would provide additional information on where there is TP Deliverability remaining on the system within the TPD allocation report itself of as a supplemental report to the Phase 1 study. Provision of this type of information would be helpful and should be pursued. Additionally, CAISO should provide the results of the TPD allocation study, the 5% dfax circle for identified constraints and deliverability in tabular or online map formats so they can be easily visualized by stakeholders and used for their assessments. Without having this information in tabular or online map format, it can be challenging for developers to understand what projects/substations fall within the 5% dfax circle and which ones do not. Having this information in a more usable format would be greatly beneficial to developers seeking to site and develop projects in areas where there is deliverability.

Under item #4 within “Transmission Information,” ACP-California reiterates our appreciation for CAISO and the PTOs holding the quarterly Transmission Development Forums. The first Forum was very useful in understanding project status and we look forward to participating in the next Forum later this month. In past comments, ACP-California requested that the information provided in those forums be standardized and improved upon. Specifically, we requested that all updates being provided include:

  1. The original anticipated in-service date for the project was first approved/included in a LGIA
  2. The expected in-service date that was presented at the prior Transmission Development Forum
  3. The current expected in-service date
  4. Metrics on the amount of capacity in the queue which are dep on the relevant project to interconnect or achieve deliverability
  5. Primary cause of any delays in development that are occurring


We continue to believe that the standardization and augmentation of information presented at the Transmission Development Forums, in line with ACP-California’s recommendations in past comments, will be helpful in addressing transmission development delays.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:

As mentioned above, ACP-California requests that CAISO provide Cluster deliverability study and TPD study results in excel or csv format.  And we request that CAISO provide 5% dfax circle data from the TPD Allocation reports in an online map or GIS format.

3. Please provide a description of what value it brings by providing such data:

ACP-California believes data visualization will enable stakeholders to easily identify locations on the grid with available transmission deliverability and to easily understand which substations are included within the 5% dfax circle.

4. Please provide the priority of the change being requested (high, medium, low):


5. Other comments:

ACP-California appreciates CAISO’s efforts to improve data transparency and looks forward to continuing to work with CAISO and stakeholders to improve data accessibility and transparency of interconnection queue and transmission-related information.

AES Clean Energy
Submitted 04/19/2022, 03:16 pm


Bridget Sparks (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

AES appreciates the CAISO’s effort to document the location and availability of existing data of value to interconnection customers, and the CAISO’s willingness to consider what additional data may be necessary to facilitate a more robust interconnection process. AES submits eight data requests for the CAISO’s consideration and would be happy to discuss any of these requests in further detail with staff.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:
    • Request 1: The CAISO should list all equipment (line and substation) under CAISO control. This data should be provided in excel to enable it to be filtered and searchable. We would like to see the ownership and operator of all lines and substations in a central location, but if coordination with the other PTOs is too burdensome, then the CAISO should just provide information on the equipment it controls.


    • Request 2: The CAISO should provide real time updates on project status, parking status, as well as portions of queue positions that are already online (along with their resource IDs), and GIA suspension status within the existing interconnection queue. This data already exists and should be made transparent to all stakeholders.


    • Request 3: The CAISO should provide Monthly or Quarterly updates on ongoing studies status done by CAISO. The CAISO should also include in the interconnection report when a queued project impacts an affected system and which system is affected.  This information could be served through market notices and should be sent to all parties not just those with projects in the relevant queue. For example, MISO provides regular updates on its Definitive Planning Phase (DPP) Study Cycle through a report presented at its Interconnection Process Working Group Meetings.[1]


    • Request 4: The CAISO should release the deliverability assessment base cases for each cluster as soon as they are created. This data can be provided in its existing format, but there is often a delay in publication, and we would like access to base cases sooner.


    • Request 5: The CAISO TPD report should include the list of Non-Operational Prior Commitments by queue position and status.


    • Request 6: The CAISO should provide more information on Short Circuit Duty capacity per main substation equipment type. Ideally, this data should be provided through a heat map that shows a short circuit duty gradient per substation voltage/ bus.


    • Request 7: The CAISO should provide an open bay position list or list of substations able to be expanded within existing fence. This information could be provided as a PDF list, excel sheet, or map.


    • Request 8: The CAISO should provide more visibility in the TPD area reports of the results of the Local Capacity Technical Study reports, which shows the need of generation at each local area and sub area. Currently the deliverability reports are broken out by PTOs and constraints. It would be helpful to provide additional information about how these areas map onto the local area and sub areas as designated in the LCRs. It would also be helpful to provide information on what additional capacity needs have been identified in the LCR reports in the TPD reports, to help inform future interconnection queue requests.


[1] See for the most recent example of the DPP Study Cycle Update. 

3. Please provide a description of what value it brings by providing such data:
    • Request 1: This would enable developers to know which process they should use- CAISO interconnection study process or the PTOs WDAT. This would also save CAISO staff time from having to field questions by developers on what assets are CAISO controlled.


    • Request 2: These reports would provide greater transparency on resource build out.


    • Request 3: These reports would provide greater transparency on the CAISO’s progress through each study and milestones. It could also enable generators to better coordinate with the affected system.


    • Request 4: Access to the base cases sooner would allow project developers to review the interconnection projects deliverability as soon as possible, and to allow more time to prepare for the next cluster’s project submissions.


    • Request 5: The list of projects and their status would help developers understand where stalled projects exist and TPD allocations may free up in the future.


    • Request 6: Overstressed Circuit Breakers in cluster studies have been carrying very long timeframes to replace. Having some way to understand and avoid overstressed CB’s in the system is just as important as avoiding overloaded transmission lines and transformers. A large percentage of overstressed equipment at a substation can result in less preferable alternative methods to solving SCD. This can result in additional power flow studies, higher costs, longer durations, and changes in POI. Additionally, the state has mandated the sunset of SF6 equipment, which has resulted in using these alternative methods. Having the data would help developers avoid these known areas of SCD issues.


    • Request 7: Some substations are completely maxed out and would require acquisition of new land at great cost and long schedule duration that makes projects non-viable. PTO’s should find a way to let developers know which substations are more easily able to accommodate incoming gen-ties.


    • Request 8: The 2022 TPD report shows that most areas have little to no remaining deliverability, which could deter developers from pursuing projects in California since these projects will likely require more upfront costs to finance these in additional upgrades. However, if the TPD reports provided more information on how each TPD area maps onto the Local RA areas and projected capacity needs this could provide clearer market signals to encourage developers to continue to site projects that can fulfill these identified Local RA needs.
4. Please provide the priority of the change being requested (high, medium, low):
  • Request 1: High
  • Request 2: Medium
  • Request 3: Medium
  • Request 4: Medium
  • Request 5: High
  • Request 6: Medium
  • Request 7: Low
  • Request 8: Low


5. Other comments:

AES appreciates the CAISO’s openness and willingness to explore opportunities to provide greater data transparency to interconnection customers. As a complement to these data transparency efforts, the CAISO should also review its process for getting access to the Market Participant Portal. Likely much of the data requested by stakeholders in this initiative will need to be accessed through signing NDA agreements. In AES’s experience, this process can be lengthy. Some AES staff that have had to wait almost nine months to gain access to the portal due to administrative and technical barriers and burdens. The CAISO should look for opportunities to streamline or further automate this process to prevent additional delays for interconnection customers.


California Energy Storage Alliance
Submitted 04/19/2022, 06:04 pm


Jin Noh (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

CESA appreciates the ISO’s Data Transparency Initiative as a key Phase 1 item since these efforts will facilitate smarter siting decisions (especially where there is available transmission deliverability), inform decisions to proceed or withdraw from the queue (thereby potentially managing the overheated queue), and support procurement decisions by load-serving entities (LSEs). With much of this information in an accessible format, the ISO may mitigate (though not eliminate) superclusters in the future, where interconnection customers would more logically select points of interconnection (POIs) that make the overall interconnection process smoother, efficient, and manageable. At a high level, CESA believes that the preliminary Data Transparency Matrix is generally comprehensive but could be presented or summarized in a more useful way, such as in one consolidated format without looking at multiple reports or in a way that is consistent between resource and transmission planning activities.

CESA offers comment on select data categories included in the preliminary Data Transparency Matrix:

  • Availability of existing and interim deliverability: CESA believes that several transmission data categories capture information that could be used to calculate remaining deliverability, such as the MW available without upgrades, as well as where and how much Transmission Plan Deliverability (TPD) remains. CESA supports efforts to make available deliverability information more centralized and readily available and accessible. Additional information on the phasing of projects could support these ends as well. Moreover, CESA requests further information on interim deliverability that is available that could support near-term projects and allow some projects to come online earlier and be procured to meet near-term reliability challenges until the actual, necessary upgrades are constructed to support all relevant projects in a cluster. This information may be readily available somewhere, but it was not captured in the preliminary Data Transparency Matrix.
  • Resource ID, technology type, and fuel type: CESA generally supports greater transparency into the status (e.g., online, suspended, withdrawn) and ID of projects in the queue. To the degree that this information is already available, this information will be helpful for all interconnection customers and LSEs to assess the prospects and costs of interconnection relative to other projects in the queue. The ISO’s proposed efforts to restructure and simplify the column for resource “fuel type” is helpful and could presumably be implemented with minimal effort. In addition, CESA believes information on the selection of either the hybrid versus co-located market participation option, as well as the MWh and technology type of energy storage resources likely represent low-lift implementation tasks that could also inform procurement activities and policy discussions.

As the ISO aims to make it easier to access information across multiple reports in a consolidated way, CESA also requests that the ISO consider ways to structure the information to make it easier for stakeholders to follow the “bread crumbs” of all the presented information. That is, the ISO should consider ways to establish a consistent list of data fields used in reports that flow between resource and transmission planners. For example, some CESA members have reported on the different zones used by resource planners for the purposes of the Integrated Resource Plan (IRP), in contrast to those used by ISO transmission planning. Such discrepancies create an additional burden for stakeholders to identify how planned transmission upgrades may align with planned or future generation and storage, or it could lead to error on the part of interconnection customers in making these calculations and determinations for rationally siting new-build generation and storage. While not a transparency issue per se, this recommendation would support the accessibility and usability of information, which advances the goal of the Interconnection Process Enhancements (IPE) Initiative to manage the overheated queue and facilitate rational siting decisions.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:

CESA supports the following additional specific data to be made transparent and publicly available:

  • Site exclusivity information: Notwithstanding the ISO’s IPE Draft Final Proposal on site exclusivity requirements, CESA recommends that the ISO also include information on whether interconnecting projects have site control as part of generator-related data transparency efforts, which is likely easy to implement and could support efficient decision-making for interconnection customers to move forward in the process. For example, knowing that many other projects in the queue and at a given area have site control, it may inform developers on whether to move forward with submitting a deposit in lieu of site exclusivity, which is currently being proposed to have a greater portion of the deposit at risk.
  • Appropriate interconnection queues by POI: In line with the Phase 1 proposal included in the IPE Draft Final Proposal, CESA supports the implementation of the proposal to differentiate POIs and locations by whether the interconnection is jurisdictional to the ISO-controlled grid versus the Wholesale Distribution Access Tariff (WDAT). This information should be provided in Excel format in the near term, with long-term plans to make it available in an online map.
3. Please provide a description of what value it brings by providing such data:

CESA supports the following additional specific data to be made transparent and publicly available:

  • Site exclusivity information: By making this data transparent, developers will have better information on their project viability relative to others in the queue, and it can potentially facilitate management of the current overheated queue. 
  • Appropriate interconnection queues by POI: This proposal would avoid inefficiencies and lost time and resources to moving through the wrong interconnection process. 
4. Please provide the priority of the change being requested (high, medium, low):

CESA provides our recommended prioritization of some of the select data categories or areas above:

  • Availability of existing and interim deliverability: High
  • Site exclusivity information: High
  • Appropriate interconnection queues by POI: Medium
  • Resource ID, technology type, and fuel type: Medium
5. Other comments:

While generally supportive of the efforts to increase data transparency, CESA also cautions that the any implementation of the above be balanced or pursued in a way that does not pull already-stretched ISO staff away from timely and efficiently completing technical studies in support of mid-term procurement needs. As ISO staff have discussed, a good portion of the information listed in the Preliminary Data Transparency Matrix is already available in the prior-cluster Area Reports accessible in the Market Participant Portal, but it requires the interconnection customer to obtain the desired information in multiple different reports and summarize themselves. To this end, CESA recommends that the ISO staff focus initially on presenting the disparate information into an Excel format and automate the process for updating and refreshing this information, while implementing some other data presentation features, such as online maps for the transmission system that may take a lot of time, resources, and IT-related considerations, to a later implementation phase.

However, we also note that efforts around organizing and making various data available in online maps is still worthwhile and important. Like the hosting capacity maps that the California distribution utilities have developed for distributed energy resources (DERs),[1] the ISO should also consider making information about deliverability, site exclusivity, queues by POI, and resource ID, technology, and fuel type available in a user-friendly online map. For reference, the Alberta Electric System Operator (AESO) just recently launched a Transmission Capability Map.[2]

Overall, before finalizing which areas to improve data transparency, CESA requests that the ISO staff provide information on the implementation challenges, costs, and timelines of any of the stakeholders’ requests, which may help all stakeholders to assess which are worthwhile and/or which are critical for near-term implementation. In addition, the feasibility of the frequency of data refreshes will be a critical criterion to whether and how to move forward with various transparency efforts.




Submitted 04/19/2022, 05:10 pm

Submitted on behalf of


Raeann Quadro (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

EDF-R is excited to engage with the CAISO in this effort to improve upon the existing interconnection data and overall interconnection and transmission process efficiency. As discussed on the call, providing data in a transparent and accessible way serves both stakeholders and the CAISO. EDF-R encourages the CAISO to undertake these data transparency efforts requested by stakeholders even in the event that implementing the change requires some technical changes to CAISO systems. These efforts will have compounding benefits over time and are very much needed at this critical inflection point for generation and transmission development.

EDF-R acknowledges that the wider stakeholder community is interested in many different kinds of data being made available, however EDF-R requests CAISO keep this IPE Data Transparency effort limited to Generator Interconnection and Transmission related data. With the specific exception of curtailments and outages, market data is out of scope for the Interconnection Process Enhancements initiative.

EDF-R’s highest priorities in this initiative are:

  • Interconnection queue improvements
  • Interconnection Queue resource_ID level phase level reporting
  • The creation of unique transmission upgrade numbers to eliminate confusion caused by changing transmission naming conventions between engineers and various reports

In order to facilitate progress tracking for the data transparency effort itself, we would appreciate the CAISO continue to add to its data transparency matrix and publish a final comprehensive list of the requested data points as and for the CAISO to provide a routine update on the transparency efforts, perhaps in the context of the existing Transmission Development Forum.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:

Below is a list data we hope the CAISO will make transparent, and by transparent data we mean data that is accurate, available to the interconnection customers, and accessible to the average stakeholder. This specifically means (1) clear definitions on what the data represents, (2) clear naming conventions that allow the data to be mapped and related to other CAISO data, and (3) formatted in a manner that allows analysis of the data.

Generator Interconnection Data


Data point

Format and Implementation



Resource ID

Please provide Resource ID in the RES_ID format as shown in RIMS NRI module as well as the MasterFile.

Please provide this information in a new column on the CAISO Queue Report. The Queue Position: RES_ID relationship is many to many, and it is understood that in some project arrangements it may take additional analysis to understand the data.

Resource IDs are already public information and published all over OASIS and For example: master control list, NQC sheet, outage information, various OASIS reports


Transmission Planning Study Area and Sub Area

This information would be provided in text, and ideally would be controlled for consistency. For example, East of Pisgah should only be shown as "East of Pisgah" or "EOP" but not both.

This information currently exists in the APP&STUDY module. Please make this information public in a new column on the CAISO Queue Report.

See below, planning sub areas.


Partial Capacity Deliverability Status percent or MW amount

This information currently exists in the APP&STUDY module. Please make this information public in a new column on the CAISO Queue Report.

CAISO queue already shows which projects have, or have requested FCDS, but the same clarity on PCDS projects is not provided; this is inequitable.

The information will also be helpful in understanding deliverability constraints and TPD results. This information is also helpful for developers during contract solicitation processes.


Phase level nameplate MW, interconnection capacity MW, Fuel Type, Technology, In-Service Date, COD

Please provide this information either as an additional tab on the CAISO queue report, or a new report in the RIMS_PUB module. Please provide this report in the RIMS module so that it is updated on an automatic cadence as the CAISO Queue Report is, rather than an excel workbook that would have to be updated manually.

It is understood that this information would be on a RES_ID basis that may not reflect Phasing as it is organized in the LGIA. It is also understood that ISD and COD may not match exactly to contract dates. These clarifications could be provided in a public data dictionary.


Very high

Restructure the fuel type by column (wind, solar, BESS) rather than Fuel-1, Fuel-2, Fuel-3

Example attached in xlsx format.

This small change will significantly the functionality of the data already in the report.

CAISO reports this is complete internally as of March 2022.

CAISO’s queue organization seems to have been changed this March, but the change does not reflect the requested ask.

CAISO’s change took column order from:

  • Type-1
  • Type-2
  • Type-3
  • Fuel-1
  • Fuel-2
  • Fuel-3
  • MW-1
  • MW-2
  • MW-3
  • MW Total

And changed them to:

  • Type-1
  • Fuel-1
  • MW-1
  • Type-2
  • Fuel-2
  • MW-2
  • Type-3
  • Fuel-3
  • MW-3

This does not represent the ask to restructure the fuel type by column.

In order to portray data in a consistent and organized way and facilitate data accessibility the request is for the data to be presented in a column order form that looks like:

  • Storage-1
  • Battery-1
  • MW-1
  • Solar-2
  • PV-2
  • MW-2
  • Turbine-3
  • Wind-3
  • MW-3

An example of this is also attached in xlsx format.


POI Data

Please clean up POI data and add a data quality control feature

POI consistency

Currently the POIs in the queue are created via text box. This leads to inconsistent POI listing and the need to manually clean data. Here is an example:

  • Whirlwind Substation 220 kV
  • Whirlwind Substation 230 kV
  • WHIRLWIND Substation 230 kV
  • Whirlwind Substation 230 kV
  • Whirlwind Substation 230kV

Instead, these should all show up in the queue as one listing:

  • Whirlwind Substation 230 kV

A dropdown list, editable via UI or with IT driven updates, could address changes needed as new POIs come about via transmission changes or in new interconnection requests.


Application LGIA suspension information

Please provide GIA Suspension information in the CAISO Queue Report.

Either the Interconnection Agreement Status or Project Status would be an efficient place to add this data.

Currently CAISO only has three statuses in the CAISO Queue Report: "Active" "Complete" and "Withdrawn" and two statuses Interconnection Agreement Status column. The CAISO's report does not indicate if an LGIA has been suspended.

This information is crucial to understanding the state of the queue, and CAISO's PTOS and other ISOs provide this information in their queues.




Transmission Planning Data


Data point

Format and Implementation



1.       Transmission Planning data improvement opportunities:

 Transmission upgrades are called by many different names over various reports. EDF-R requests CAISO apply unique identifiers to transmission planning process (TPP) upgrades approved by the Board as well as transmission that is identified as needed in the Generator Interconnection Deliverability Allocation Process (GIDAP). The format for this identifier could be consistent with projects as they appear in the RIMS TRANS module:

  • 22TRANS21353

 Creating this primary key for transmission upgrades (similar to queue position or resource_IDs) will allow for stakeholders to better understand the progression and status of network upgrades, and will enable developers take a proactive approach to monitoring the transmission projects critical to their projects, and will facilitate their ability to provide good feedback at the CAISO’s Transmission Forum.


EDF-R hopes the CAISO will make many of the transmission data improvement changes requested by stakeholders, but views this item as foundational and as having the highest return on investment to stakeholders and the CAISO.

Very High

a.       Share study report data available across multiple reports in an excel document (posted on NDA site) 




b.       Create a transmission project tracking report with information from TPP appendices and RIMS Transmission module

 EDF-R requests the CAISO produce this report from RIMS, and have it be a complete set of identified transmission upgrades from inception (either TPP or GIDAP) through completion. This would require the CAISO and PTOs to reconcile what PTOs are submitting into RIMS TRANS module to avoid duplicates.


As with interconnection requests, CAISO could apply its unique label to these proposed transmission upgrades to facilitate transparency and tracking from the bid to build process.  



c.       Ideally transmission data would include, element upgrade name, description, region, expected in service date, From_Sub, To_Sub, model identifier, voltage, project status, line miles, and facility rating MVA

 In line with item b above.



d.       Implement online maps for the transmission system that details where capacity is available, similar to existing distribution information;




2.       Define what MW level could move forward without upgrades;

 Please provide this as information in each area study report.

 This information will give developers more information on the viability of the interconnection area and of the queue cluster’s marketability.


3.       Information on resource curtailments by specific planning sub-areas;


 EDF-R is also interested in better understanding the relationship between the system location of one or more RAS implementation as it compares to curtailment. The CAISO provides a daily look at renewable curtailment here: California ISO - Managing Oversupply ( but the information is not at the appropriate granularity for correlating it to specific areas. EDF-R requests the CAISO provide some more data related to the congestion and curtailment for RAS zones, including specific areas where RAS schemes increase congestion and curtailment, how many MWh are curtailed annually, and what the cost to the system is. 


4.       Project transmission upgrade tracking/status information; - Transmission Forums

 As described in item one, EDF-R requests CAISO apply unique transmission ID numbers to facilitate tracking.



5.       Data on constraints, TPD allocation remaining and areas; percentage of PCDS; project in service dates; and % of projects that reach completion. 


EDF-R requests this information be added to the Public Queue Report in a new column, and included on the new proposed “phase report” to be reported at the resource_ID level


6.       Define the study area boundary in the area reports.

 Similar to the Transmission Planning Study Area and Sub Area in the Generator Interconnection section above.



7.       Transmission grid data transparency including transfer capability, deliverability constraints, curtailment based on local congestion.




8.       Better differentiation within clusters – specifically define the amount of overload that requires the upgrade to be added to the project.  This information should be available in all PTO reports.




9.       Information provided about areas where TP Deliverability is still available, and how much. The annual TPD Allocation Reports contain useful information about areas where deliverability has run out but relatively little information about where, and much, deliverability remains.

 This information would be helpful, as well as specific content for what projects makeup the deliverability held in reserve for non-operational generation



10.   ADNUs/other upgrades: This TPP cycle has included a useful discussion about use of the ISO’s Transmission Capability report to identify potential cost-effective transmission upgrades to provide additional TP Deliverability in areas of high commercial interest. LSA/SEIA would like the ISO to refine this information to make it useful in identifying “low-regrets” transmission upgrades, for policy purposes.




3. Please provide a description of what value it brings by providing such data:

  With timely access to accurate and complete data stakeholders and CAISO will experience multiple benefits:

  • Improved quality of submissions to the CAISO’s transmission planning process
  • Improved ability to present the CAISO with empirically supported policy proposals in stakeholder initiatives
  • Help market participants make more informed decisions when going through the procurement process, likely leading to reduced number of interconnection requests
  • More thoroughly consider requests of the CAISO before submitting those requests to the CAISO (such as material modification assessments)
  • Better understand CAISO’s generator interconnection and transmission planning processes because specific context breeds familiarity

With CAISO’s own analysis we can see that many of the data points requested by stakeholders are already available in other CAISO provided resources. This information highlights two important points 1) any confidentiality hurdles, if they exist, are known and 2) an enormous amount of productivity is being lost to stakeholders independently cleaning up CAISO data sources so that the data is coherent and can be related to non-CAISO sources. This data analysis is performed by businesses for all kinds of reasons, development strategy planning, financial projections and analyses, public policy development, independent reviews; et cetera.

4. Please provide the priority of the change being requested (high, medium, low):

  Provided in context above.

5. Other comments:

EDF-R reiterates its request for transparency in the context of this transparency effort.

EDF-R requests CAISO record and share progress tracking for the data transparency effort itself, we ask that the CAISO update its data transparency matrix and publish a final comprehensive list of the data points stakeholders requested. EDF-R also asks for the CAISO to provide public listing of the status of each ask, CAISO’s position, and the priority and timeline for the ask (or reason for refusal to deliver. We request CAISO provide a routine update on the transparency efforts, perhaps in the context of the existing Transmission Development Forum.

Submitted 04/19/2022, 06:21 pm

Submitted on behalf of
Large-scale Solar Association


Susan Schneider (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

LSA appreciates the CAISO’s follow-through on stakeholder requests for additional data transparency in the interconnection and related processes.  LSA’s comments below are focused in two main areas:

  • Enhancing developer ability to bring projects on-line faster.  LSA supports the CAISO’s recent establishment of a quarterly transmission-information update and has a few suggestions for additional transparency.  We also continue to support our earlier request that the CAISO perform additional analyses in interconnection studies to identify capacity that could reach COD before all upgrades for the cluster are complete.
  • Identifying areas where projects might drop out and/or potential deliverability-transfer opportunities. 

Until CPUC portfolios reflect actual deliverability needs in the market and trigger additional upgrade, and/or until the CAISO’s annual Transmission Planning Process (TPP) is reformed to reflect the longer-term needs identified in the 20-Year Outlook, deliverability will continue to tighten throughout the CAISO system. 

For example, the TPD (non-) award table for the Desert Constraint area in the 2022

TPD Allocation Report, limiting deliverability of generators in the Arizona and Riverside East renewable zones, shown below.  (The fornat did not transfer well into this comment tool.)

Table 3.17 - TPD Allocation for Generation behind the Devers-Red Bluff Area Constraint

Non-Operational Prior Commitment (MW)


Eligible TPD Candidate (MW)


TPD Allocated (MW)


Remaining TPD available (MW)


At best, any relief of the constraints causing these limitations may take years to be approved in the TPP and more years to come on-line.  Any near- or medium-term success in such areas, for projects needing deliverability, will depend on developer ability to find, obtain, and utilize deliverability already awarded to projects that may not be progressing – either through deliverability transfers that allow such projects to monetize their deliverability award and drop out, or through drop-outs likely to occur anyway that would free up previously awarded deliverability. 

This is especially true for energy storage capacity, which is expected to play such a critical role in the state’s significant efforts to reduce greenhouse-gas (GHG) emissions through renewables integration and fossil-fuel phase-out.

LSA’s recommendations below are classified into the same categories as the CAISO data matrix – Interconnection Queue and Transmission Plan Deliverability (TPD)/Transmission information. 

LSA’s suggestions for content, venue, and format are not definitive.  Generally, we would support information that is broadly available (public, to the extent possible), and we rely on responsive information from the CAISO about the reasonableness of providing this information in different ways.

Consistent with that perspective, LSA encourages the CAISO not to overestimate the specificity of stakeholder-requested information.  Instead, LSA hopes that the CAISO will try to understand the objectives of these information requests and, if the requested information cannot be provided exactly as requested, suggest other information that could be provided that might meet stakeholder objectives nearly as well, or even better. 

The CAISO has a better picture of its own capability than any stakeholder, and we hope this initial effort will transform into a two-way dialog to reach mutually beneficial solutions, and continue beyond this initial workshop.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:

Interconnection Queue information

  • Starting point:  LSA supports Gridwell’s suggestion to: (1) examine the CAISO tariff to determine the information that must be kept confidential; and (2) survey other ISO/RTO jurisdictions to determine their rules and practices.  This will provide a starting point for the discussion concerning data confidentiality.
  • Updating:  LSA supports SDG&E’s suggestions to “clean up” the queue listings, e.g., projects that have gone past their listed CODs by more than 6 months (Construction Sequencing deadline) or do not have GIAs after many years in the queue.  (This may be more of an “enforcement” update, i.e., rather than an issue with the listings, the CAISO needs to make sure it is keeping up its efforts to ensure that projects do not languish in the queue.)
  • Organization:
  • LSA supports SDG&E’s suggestions to:
  1. Standardize characterization of POI names.  For example:
  • Substation names, e.g., “Red Bluff 220 kV” vs. “Red Bluff Sub 230kV Bus” vs. “Red Bluff Substation 220 kV”
  • County names, e.g., “San Bernadino” vs. “San Bernardino” vs. “San Bernardino County”

2. Show technology/fuel types by individual columns, instead of Fuel 1, Fuel 2, etc.

  • LSA supports New Energy Works’ suggestion to provide project suspension status and GIA status information (not just “Executed” or blank).
  • LSA also recommends adding:
  1. PCDS information, for projects as a whole and individual phases (see below), so developers can see how much deliverability was awarded to those projects and phases.
  1. Information for different project phases, where a project is formally phased (information already available in public GIAs anyway but laborious to track down individually). 

LSA wonders if inconsistency in defining “COD” may be responsible for listings of projects that have come on-line in phases, e.g., perhaps one phase has reached Commercial Operation by the “COD” in the listing but the entire project has not, and the CAISO usually defines a project “COD” as when the entire project reaches commercial Operation.

  1. TPD allocation group.  For example, a project with a Group 3 allocation that is close to its stated COD but has not yet begun construction may be a potential drop-out candidate, while more Group 2 allocations will likely have been awarded than projects actually retaining those awards through executed PPAs.
  1. PPA status.  As the CAISO recognizes, this is a key viability indicator.


Transmission/TP Deliverability information

  • Differentiation within clusters:  LSA continues to support our earlier recommendations that the CAISO:
  • Include in Phase II Studies an examination of the longest lead-time Network Upgrade and determine/state the MWs that could connect without it; and
  • Allow projects with earlier requested CODs (before the upgrade would be triggered) to use a COD in their GIAs without the upgrade, subject to change if they later delay their CODs to be after others in the cluster. 

This element is particularly important with late identification (after the first Phase II Studies were complete) of upgrades significantly delaying project CODs – e.g., the recent SDG&E circuit-breaker upgrades, where nearly the entire affected cluster could come on-line without the upgrades.  The CAISO should minimize the significant harm from such late-identified changes by limiting the delays to projects that actually require those upgrades.

  • Transmission project information:  Where project names have changed, provide information enabling tracing back to the earlier names (e.g., “Lockeford-Lodi” to Lode-Lockeford” to “South San Joaquin Transmission Project”).  This should be done in the new quarterly transmission status updates, as well as the annual Transmission Plan and other PTO information forums.
  • Annual TPS Allocation Reports:  Provide much more information about:
  • Estimated available TPD in areas where it has not “run out.”  We understand the analytical difficulties involved with this estimation, but the information is critical for project siting analyses.

For example, MISO provides a “heat map,” shown below, indicating constrained areas of the system where constraints limit deliverability.  MISO also provides an accompanying tool that screens for constraints and provides information for potential POI testing.  Further information is available at


  • More information about the projects holding the already-allocated TPD in each area, e.g.  
  • Queue clusters of the projects
  • Allocation groups
  • Projects/capacity holding executed PPAs
  • Time in queue

In areas where TPD has “run out,” this information may help determine the likelihood that any TPD might become available from project drop-outs in the future, like the information suggested for addition to the Interconnection Queue above.


3. Please provide a description of what value it brings by providing such data:

Rather than repeat its requested list, LSA included that information in its responses to Q2 above.

4. Please provide the priority of the change being requested (high, medium, low):

The highest-priority items above that are aimed at identifying remaining available TPD and speeding CODs – updating and enhancing the queue listings, identifying areas were TPD is still available, and allowing projects within clusters to proceed faster.

5. Other comments:

No additional comments.

Nancy Rader
Submitted 04/19/2022, 01:28 pm

Submitted on behalf of
California Wind Energy Association


Songzhe Zhu (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

CalWEA appreciates that the CAISO is open to publishing any data with stakeholders’ consent. CalWEA supports including the following information in the public queue report: study area, PCDS information, and phasing information. Resource ID to interconnection queue mapping should also be publicly available, but maybe in a separate document from the queue report. 


Study area boundary is not provided in all the area reports. CalWEA recommends all area reports including the boundary description like the SCE reports. The public document “Affected System Contact List” on the CAISO website currently has a description of each study area. The description should be updated to match the area reports and clearly identify the electrical boundary, instead of the general geographic locations.


CalWEA urges the CAISO to establish a timeline in the BPM for posting study data and include the anticipated posting dates as part of the study schedule in the study plans available on MPP. Study data should be posted a few weeks after the CAISO completes the corresponding study task through the study process. Timely posting the data helps developers make development decisions.


The TPD allocation report could include a PTO-level summary of how many candidates (and associated MW) received an allocation in the current cycle.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:

CalWEA has no comments.

3. Please provide a description of what value it brings by providing such data:

CalWEA has no comments.

4. Please provide the priority of the change being requested (high, medium, low):

CalWEA has no comments.

5. Other comments:

CalWEA has no other comments.

Rev Renewables
Submitted 04/18/2022, 04:20 pm


Renae Steichen (

1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

See below

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:

See below

3. Please provide a description of what value it brings by providing such data:

See below

4. Please provide the priority of the change being requested (high, medium, low):

See below

5. Other comments:

REV would like to request CAISO as part of Phase 2 IPE issues to re-include item 6.8 from the Revised Straw Proposal (requesting the PTO/ISO should start planning for all upgrades after NTP that are required for a project to attain FCDS). CAISO stated previously that it would raise this issue in the data transparency forum, but it was not a part of the agenda and the forum does not address our concerns regarding the PTO delays to plan and build transmission upgrades to attain FCDS after notice to proceed is issued by a developer.

This issue applies to both standalone and shared network upgrades. There have been instances where upgrades such as new Remedial Action Schemes are triggered by a group of projects, but CAISO/PTOs wait to start planning for these upgrades until enough projects achieve commercial operations. This delay can cause material risk to the first project, which stays under an Interim Deliverability status until the required upgrade is built. The deliverability status of this project is tested every year under the annual process which is conducted around middle of the year (annual NQC deliverability study) and if enough deliverability is available this project is allowed to be full capacity for the upcoming year. The concern with this approach is if the annual deliverability process does not show enough deliverability, CAISO and the PTO may then decide to build the required upgrade but this may be too late for this project to sell full capacity Resource Adequacy for the upcoming year. It also may too late for the project to meet its obligation to provide Resource Adequacy to its counter party if it already has a contract, thereby leading to material financial implications for the project. In addition, this could cause a reliability risk for CAISO if supply conditions for the upcoming year are constrained.


Therefore, REV proposes that in situations described above when the first project issues NTP to the PTO, PTO/CAISO should either:

  1. start planning for all upgrades required for FCDS status, including upgrades triggered by a group of projects (note that in this instance the first project could post security for the new RAS scheme as needed), or
  2. allow the project that is ready to achieve COD to proceed as FCDS if CAISO/PTO make a determination that the network upgrade doesn’t get triggered if only this project proceeded forward.


In addition, it will be helpful to further discuss issues related to deliverability status if the project achieves COD and does not trigger the need of shared upgrade itself based on annual NQC studies. In this instance, REV strongly believes that giving FCDS status to projects creates financial incentive to bring the project online in a timely manner and reduces development risks for projects.

San Diego Gas & Electric
Submitted 04/19/2022, 06:21 pm


Eusebio Arballo




1. Please provide your organization’s comments on the Interconnection Process Enhancements (IPE) 2021 - Data Transparency April 5, 2022 stakeholder call discussion:

SDG&E requests CAISO include the following in the list of improvements for increased data transparency and accuracy:

  • Consistency in Generation Types as they are entered in RIMS. 
    • For Mixed generation types, Solar, Wind or any other should be listed first, with BESS listed second. A BESS should be listed first only for stand-alone BESS systems.
  • Consistency in naming convention for POI locations. 
    • Solicit PTO input for preferred naming convention for each POI. 
    • Consider adding POI to CAISO Grid Assets (non-granular)
    • Use a different method of uploading the POI information from the IC.  A field that is automatically filled from the Interconnection Request to RIMS would be preferable.
    • This request aligns with stakeholders’ request for all POIs within the PTO’s study area to be made available. 
  • Utilize 3rd party software for interconnection applications and data/file management.
    • Move to a web-based interconnection application for both initial IR and MMAs
    • Create drop-down list of POIs in each study area
    • Version documents for rounds of IR validation
    • Maintain “final” version from IR validation for future IC use during Appendix B and MMAs
    • None of the files from App & Study (Appendix 1, Attachment A, SLD, kmz, inverter data, short circuit data, P/Q curves, EPCs, DYDs, flat run and bump tests, MW plots from Phase I, Phase II, Reassessments, MMAs, etc.) are the same as the ones that are uploaded to RIMS by the PTO (or the IC) in advance of the backfeed date (sliding scale based on FMN schedule, between 84 and 160 days). 
    • NRI process can be managed separately to upload the necessary files, etc. to ensure the connection to the Network Model, etc. are maintained
  • Show Project Phasing in RIMS
    • Separate line items for each
    • Separately show phases ISD, TOD and COD and accurately reflect project status when each phase is complete.
    • Show associated phase capacity (MW)
  • Utilize RIMS for MMA processing (unless 3rd party software proposal is adopted)
    • Move away from emailing IC files to PTOs for review
    • When MMAs begin, the IC is expected to essentially provide a complete interconnection request worth of documents. The IC often uses an old version of the documents as a starting point, which puts a lot of burden on the IC, PTO and CAISO to start the IR validation over, not just make the minimal change as the MMA requested. 


SDG&E requests CAISO to elaborate on the following:

  • Why is CAISO not in a position to move away from RIMS? 
  • What is driving the reliance on RIMS?  Within CAISO there isn’t consistency between groups (Queue Management, Interconnection Specialists, Contracts) on the use of RIMS. 
  • What is the essential connection between RIMS and other systems within CAISO that drives the requirement that RIMS must be used for all aspects of the interconnection process?
    • The CAISO RIMS enhancements initiative workshop showed there is more necessity around the Network Model connection to the market or real-time system, than data from the interconnection application and study process. 
  • Does CAISO have a process map or document that describes each step of the process as it relates to RIMS?


SDG&E requests a regular cycle for “queue clean-up”, quarterly at the same time as quarterly reports

  • Milestone dates kept up to date
    • projects that go past their stated milestone dates
    • projects that park which result in milestone date changes
  • Status of GIA executions        
  • Phasing
  • Capacity changes
  • Technology changes/additions

SDG&E uses RIMS data to perform operational studies which can become inaccurate and obsolete without the data residing in RIMS being updated regularly.

2. Please provide any additional, specific data you believe the CAISO could share publicly and in what format would you like to see such data published:
  • SDG&E is not requesting any additional data to be published, only to clean up the current lists and improve the processes in which data is managed.
3. Please provide a description of what value it brings by providing such data:
  • Increased accuracy and less burden to CAISO, PTO and IC for data validation.
4. Please provide the priority of the change being requested (high, medium, low):
  • Medium. These changes should be implemented in advance of Cluster 15 application period.


5. Other comments: