Docket Nos. EL21-77-000, EL21-77-001, EL21-77-002,
ER22-2371-000, ER22-2372-000

I concur with the Commission’s orders in these proceedings because I agree that the conclusions they draw are the correct application of the Commission’s existing precedent regarding “but for” cost causation.  It is reasonable for SPP to use a de minimis threshold when assigning costs to interconnecting projects, and to determine “but for” costs based on network upgrades that would not otherwise be built via the SPP interconnection process or another existing planning process.[1]  Under our current “but for” cost causation framework, this allocation of costs is just and reasonable.  I write separately, however, to express my concern with an issue that these cases highlight with the interplay between SPP’s interconnection and transmission planning processes.  The facts of these cases reveal a status quo design in SPP, and potentially other markets, that involves significant potential for unfairness and delay. 

As demonstrated in these proceedings, even where an individual SPP interconnection process study reveals overloads on transmission lines but does not trigger upgrades because that individual project’s impact is below the applicable TDF threshold,[2] there is no guarantee that the region’s integrated transmission planning process will address those overloads.  The integrated transmission planning process uses different dispatch assumptions than the interconnection study process, as well as different assumptions regarding which supply resources are used in the various scenarios.[3]  This may lead to a scenario where a project like Tenaska’s, when over the TDF threshold, may shoulder significant burdens for network upgrades despite a relatively modest TDF impact that is above the de minimis threshold.  That, in turn, creates the potential for queue withdrawals, and an ultimate need for restudies in the interconnection process, which will cause further delays. 

Given this system, it seems possible or even probable that some network upgrades will be so expensive as to cause a project withdrawal cycle to repeat until finally, at some point, the integrated planning process addresses those upgrades after repeated queue withdrawals.  The misalignment in assumptions and timing between the processes as currently set forth dictates that the integrated transmission planning process, if it ever addresses the overload, will only do so after the interconnection process has proceeded through one or more cycles of study followed by project withdrawal.  Surely it would be more efficient if the integrated planning process could simply identify and spur construction of the relevant projects in the first place, prior to repeated studies and withdrawals in the interconnection process.    

The Commission’s notices of proposed rulemaking on transmission planning and interconnection in Docket Nos. RM21-17[4] and RM22-14[5] hold enormous potential to improve transmission planning and interconnection processes across the country.  But while they will likely help to ameliorate the particular problem I describe, I am concerned that, standing alone, they are not adequate to fully cure this particular underlying issue.  For example, the Commission’s Transmission Planning NOPR proposes that public utility transmission providers will plan using long-term scenarios that better account for the likely influx of interconnecting generators,[6] but does not mandate or guarantee that each region will ultimately pursue projects that address these issues.  It also includes a proposal to better coordinate transmission planning and interconnection processes,[7] but that process, if enacted, would still entail potentially years of delay as projects facing these barriers must wait while the same large network upgrades are repeatedly identified and not built in the interconnection process.  The Interconnection NOPR includes provisions to discourage withdrawal of projects from the interconnection queue,[8] but does not eliminate that possibility, which may still occur with regularity if the costs of the relevant network upgrades are high enough.

Accordingly, I am left wondering if something more is necessary to address the significant disconnect present in the intersection of the SPP integrated transmission planning and interconnection processes that is apparent in this proceeding.  And I wonder whether these flaws are more universal and may occur in other regions as well, such that a generic solution is more appropriate than a region-specific proceeding.  I encourage stakeholders to file comments in Docket Nos. RM21-17 and RM22-14 to address whether the notices of proposed rulemaking put forward by the Commission are adequate to address the interconnection problems discussed herein, and whether SPP and other regions (if applicable) have plans in place to address these challenges.  I am eager to hear stakeholders’ diagnoses of the problem, as well as, if deemed necessary, proposed solutions that may go beyond those fixes the Commission has proposed thus far.  Addressing this problem implicates whether the need for a transmission project derives from the planning or interconnection process, and accordingly holds consequences with regard to who pays for the relevant infrastructure.  So, it may be appropriate for the Commission to address this issue concurrently with participant funding, should the Commission ultimately take up that issue.  Accordingly, I am interested in thoughts on how the Commission may address these issues separately, or together in a holistic manner.

For these reasons, I respectfully concur.


[1] While this fact is not emphasized in the Majority Order, I note that the fact that the relevant upgrades would not necessarily be required through the SPP integrated transmission planning process is relevant to my own decisionmaking on this issue.

[2] See Order at P 98 (“Under SPP’s method, de minimis impacts that do not exceed the TDF threshold may accumulate and ultimately lead to a transmission facility being overloaded in the study model without SPP assigning costs of a network upgrade to mitigate the constraint.”). 

[3] Compare SPP, SPP Integrated Transmission Planning Manual, § 2.1.2 (July 2017) (describing dispatch assumptions used in SPP’s ITP process) with SPP, SPP Guidelines for Generator Interconnection Requests, § 6.3 (Oct. 2019) (describing dispatch assumptions under different scenarios used in SPP’s interconnection study process).  Also, SPP only includes a generator interconnection project in the ITP study model after a GIA is executed while the generator interconnection studies include all higher-queued generation.  SPP Tariff, attach. O, § III.5.c.

[4] Building for the Future Through Elec. Reg’l Transmission Planning & Cost Allocation & Generator Interconnection, 179 FERC ¶ 61,028 (2022) (Transmission Planning NOPR).

[5] Improvements to Generator Interconnection Procedures and Agreements, 179 FERC ¶ 61,194 (2022) (Interconnection NOPR).

[6] See Transmission Planning NOPR at PP 84-90, 104-112, 130-134, 145-153.

[7] See id. at PP 166-174.

[8] See Interconnection NOPR at PP 106-110, 115-123, 128-137, 140-148.

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