PAC: MTEP24 Study Scope (20230830)

The TDU Sector provides the following feedback on MISO’s MTEP24 scope of work. 

• Underbuild or supporting transmission facilities for system buildout:  Substantial planning and buildout of the backbone transmission system in MISO is underway with LRTP.  The sector requests MISO begin focusing on the underbuild of the system which will be required to support the new overlay and connect local planning to regional planning.  The sector views this issue as an important gap in current planning efforts.  MISO noted during September’s Board Week that the Tranche 2 effort is not focused on finding solutions to all problems identified in the analysis, but on finding solutions to regional problems in particular.  While MISO has not clearly articulated how they distinguish regional problems, we suspect that—in part—MISO plans to focus on new facilities 345 kV and above, consistent with Tranche 1.  This leads us to question what MISO planning process will consider potential lower-voltage projects that may be part of a cost-effective plan to facilitate footprint-wide transfer capability.  The sector requests that MISO begin giving thought to this question in the MTEP24 process, recognizing that this would be a multi-cycle effort.  This work is needed to understand the complete picture of the transmission buildout necessary in the MISO footprint.  The sector also has concerns not focusing on this topic now could lead to sub-optimal solutions and potential unexpected congestion and other constraints issues popping up in the future.

• Congestion:  The sector requests continuation of the near-term congestion analysis performed in MTEP23, with the goal of developing ability to better replicate actual operational results and identify highly cost-effective potential upgrades.  The sector also sees a need for MISO to consider more how congestion will be managed as the buildout of the backbone system continues.

• Storage:  For several years the sector has requested that MISO perform focused study work related to on the potential impacts from widescale deployment of energy storage resources (including stand-alone and hybrid resources). This study would go further than the storage related analysis performed as part of the Renewable Integration Impact Assessment and seek to better understand the impact of storage resources on addressing renewable energy curtailments and providing fast ramping/flexibility benefits to MISO energy markets and operations.  In addition, this analysis should not just focus on 4-hour storage but also consider the potential impacts from 8-hour duration storage and longer.  The sector renews this request.   As the interconnection queue is continuing to show, the interest in storage and hybrid resources is continuing to grow rapidly.  Further, substantial storage resources will potentially be brought on by surplus and generation replacement processes.   MISO should work with stakeholders to understand how storage resources can best work with and optimize system expansion planning and renewable resource generation.

• Grid Enhancing Technologies (GETs):  The TDU Sector believes MISO should focus not only on system expansion but also how the system can be optimized.  With this in mind, the sector requests that MISO perform focused work on GETs, specifically on flow control and ways to better manage/optimize flows on the system.  For example, members of the sector have been involved with an effort with how the consideration of line compensation could be integrated into planning which was presented at the PAC in 2023.  LRTP Tranche 1, potential future tranches of LRTP projects and ongoing traditional MTEP projects are all helping to provide more system capability; a focus should now be placed on how increased capability, as well as existing capability on the system, can be better managed through flow control solutions.

Mississippi Public Service Commission (MPSC) Response to PAC: MTEP24 Study Scope (20230830)

In the August 30, 2023, meeting of the Planning Advisory Committee (PAC) MISO opened a feedback request for the MTEP24 study scope with a focus on additional/modified planning study work.

Each year, in accordance with Section 2.8.2.1 of the MISO Transmission Planning Business Practices Manual, MISO requests feedback regarding the study scope for the MISO Transmission Expansion Plan (MTEP). While the MTEP scope is fixed in part by provisions of the Owners Agreement, Tariff, and Business Practices Manuals, additional study items may be added, as necessary, from cycle to cycle. Please be aware that in addition to the core MTEP studies, MISO is performing the important Long Range Transmission Planning study requiring a significant commitment of resources limiting MISO’s ability to take on additional studies. Scope input received in stakeholder forums will be presented for discussion at the Planning Advisory Committee later this year.

Comments are due by September 20, 2023.

Feedback

The MPSC offers the following three comments:

1. Studies based on Future 2A should be revised to reflect:
• Realistic changes to load forecast.
• Dispatch of storage consistent with how those resources will be operated in the market.
• Inclusion of hybrid solar/storage projects with an appropriate accreditation that may change over time.

2. Given the Independent Market Monitor’s (IMM) pointed comments during September MISO Board Week, identifying methodological shortcomings in the study of transmission needs under Future 2A, the MPSC believes the capacity accreditation assumptions used in the EGEAS expansion plan analysis must be corrected so that they are consistent with (i) MISO’s current renewable resources accreditation proposal, and (ii) include hybrid solar-storage resources offered to EGEAS as a single joint resource.

3. Most importantly, MISO needs to study the ancillary services needs of the system consistent with the forecasted/reported retirement plans for thermal dispatchable generation and a corrected forecast for renewables likely to interconnect. Furthermore, MISO should discontinue, or otherwise address, reliance on hypothetical flexible non-pollution emitting resources in the economic modeling of energy adequacy.