SD — Power Infrastructure Updated 2026-07-17

South Dakota

MISO/SPP Data Center PPAs Queue Bottlenecks Transmission Constraints

1) Grid operator and market structure

  • RTO/ISO / balancing authority footprint: South Dakota load and generation sit across the Southwest Power Pool (SPP) and MISO footprints; SPP identifies South Dakota in its regional footprint, and MISO identifies South Dakota among the states it serves. SPP, accessed 2026-07-17; MISO, accessed 2026-07-17.
  • Retail market structure: South Dakota remains a regulated retail electricity market; EIA’s state profile shows retail sales through full-service providers and no energy-only provider sales, which is consistent with no broad retail-choice market. EIA South Dakota State Profile, accessed 2026-07-17.

2) Interconnection queue (status, wait times, data center requests, reforms)

  • Queue timing benchmark: Berkeley Lab’s 2025 Queued Up materials report that the median duration from interconnection request to commercial operation exceeded four years for projects built in 2018-2024, providing the best public national benchmark for queue timing rather than a South Dakota-specific data-center queue metric. Berkeley Lab Queued Up, 2025-12-15.
  • SPP HILL/HILLGA reform: FERC accepted SPP’s High Impact Large Load (HILL) and High Impact Large Load Generation Assessment (HILLGA) processes in January 2026; Commissioner Rosner’s concurrence described them as pairing large loads and associated generation to reduce reliability and customer-cost risks. FERC, 2026-01-14.
  • SPP CHILLS reform: FERC approved SPP tariff revisions for Conditional High Impact Large Load Service (CHILLS) on June 5, 2026, allowing non-firm, as-available transmission service for qualifying high-impact large loads while needed resources or network upgrades are put in place; the order states CHILLS has a one-year minimum term, seven-year maximum term, and is subject to curtailment during constraints or emergencies. FERC order hosted by SPP, 2026-06-05.
  • FERC show-cause proceedings for both South Dakota RTOs: On June 18, FERC opened separate Federal Power Act section 206 proceedings for SPP (EL26-68-000) and MISO (EL26-70-000), directing each RTO and its transmission owners within 60 days to justify existing large-load tariff provisions or propose reforms. The orders address application and study procedures, operational requirements, network-upgrade cost transparency and cost-shift protection, co-location, flexible transmission service, and expedited study of generation serving nearby large loads. FERC SPP show-cause order, 2026-06-18; FERC MISO show-cause order, 2026-06-18.
  • MISO large-load framework remains under development: FERC’s MISO order records that MISO lacks a consistent, transparent large-load evaluation framework and is developing large-load definitions and reliability requirements, a zero-injection generator interconnection agreement pathway for generation serving co-located load, and possible incremental or non-firm transmission service. MISO’s current public materials describe large-load projects seeking connection in 18-36 months and a three-part framework responding to the June 18 order. FERC MISO show-cause order, 2026-06-18; MISO Large Load Additions, accessed 2026-07-17.
  • Computational-load reliability standards ordered: On July 16, FERC directed NERC to file new or modified reliability standards for computational-load integration and associated registration criteria by December 31, 2026. This national reliability action applies to the bulk-power reliability risks posed by data centers and other computational loads, including those connecting in MISO and SPP. FERC July meeting summary, 2026-07-16.
  • MISO-SPP seam: SPP’s JTIQ page says the five-project MISO-SPP Joint Targeted Interconnection Queue portfolio was approved by SPP’s board on December 9, 2024, and by MISO’s board as part of MTEP24 on December 12, 2024; SPP says the portfolio is intended to address seam barriers and enable about 28.6 GW of generation interconnection. SPP-MISO JTIQ, accessed 2026-07-17.
  • Data center-specific public queue evidence: Public queue and transmission-planning materials identify large-load reforms that include data centers, but they generally do not disclose named South Dakota data-center load requests by customer; South Dakota-specific public evidence is instead concentrated in PUC electric-service dockets and local project records. FERC SPP show-cause order, 2026-06-18; South Dakota PUC EL24-027 docket page, accessed 2026-07-17; South Dakota PUC EL26-008 docket page, accessed 2026-07-17.

3) Ratepayer protection (PUC/PSC tariffs, cost allocation, dockets)

4) Generation adequacy (major projects, storage, shortfall concerns)

5) Utility load forecasts (data center demand, IRP filings)

6) Behind-the-meter / co-location / direct PPA activity

  • No South Dakota-specific direct PPA or co-location approval found in the February 1-July 17, 2026 public docket search; the new public South Dakota docket is instead an interruptible blockchain service agreement between Black Hills Power and CSRE Properties South Dakota, LLC. South Dakota PUC EL26-008 docket page, accessed 2026-07-17; Black Hills Power EL26-008 application, 2026-03-19.
  • Regional co-location pathways: SPP’s HILL/HILLGA framework creates an expedited study pathway for high-impact large loads and associated generation, while CHILLS creates conditional transmission service for high-impact large loads while firm service requirements are resolved. MISO is developing a zero-injection generator interconnection agreement process that would allow co-located generation to serve load without injecting onto the transmission system, but FERC’s June 18 order describes that work as still under development. FERC SPP show-cause order, 2026-06-18; FERC MISO show-cause order, 2026-06-18.
  • Sequitor/Steppe distributed-energy partnership: On May 26, Sequitor Edge announced a national partnership under which Steppe Energy would support natural-gas infrastructure, behind-the-meter generation, solar, battery storage, and microgrid-ready systems for future Sequitor projects, expressly including planned facilities in South Dakota. The announcement says definitive agreements would still be negotiated project by project, so it is not evidence that a specific South Dakota behind-the-meter system or PPA has been approved. Sequitor Edge, 2026-05-26.
  • Self-generation reporting did not pass: HB 1301 would have added broader reporting and decommissioning obligations for large data centers, but it failed in committee. South Dakota Legislature HB 1301 text, 2026-02-04; South Dakota Legislature HB 1301 action log, 2026-02-18.

7) Transmission constraints and upgrades

  • MISO-SPP seam constraints: The SPP-MISO JTIQ portfolio remains the main identified seam upgrade framework affecting South Dakota-adjacent interconnection economics; SPP says it addresses significant barriers to new generation at the seam and enables about 28.6 GW of generation to interconnect. SPP-MISO JTIQ, accessed 2026-07-17.
  • SPP large-load service reform: FERC accepted CHILLS on June 5 with the requested July 1, 2026 effective date, making conditional, non-firm transmission service available to qualifying high-impact large loads while firm service requirements are resolved. FERC then opened EL26-68-000 on June 18 to test whether SPP’s broader tariff still needs additional large-load, co-location, cost-allocation, and transparency reforms. FERC CHILLS order hosted by SPP, 2026-06-05; FERC SPP show-cause order, 2026-06-18.
  • No MDU South Dakota build identified in the July plan: MDU says it continues studying transmission options but is not currently proposing new transmission facilities in South Dakota, while its July 2027 IRP will be the next identified integrated-resource update. Montana-Dakota Utilities ten-year South Dakota plan, 2026-07-01.

Notes on scope and evidence gaps