The Southwest Power Pool and the Midcontinent Independent System Operator joined forces to consider a possible transmission project involving parts of Oklahoma, Texas, Arkansas and Louisiana.
The project would possibly involve two sets of 500-kV projects to provide reliability, economic and transfer benefits across their southern seam, according to a report by the two power grids.
“This report documents the completed analyses and findings from the SPP-MISO 2024–25 CSP Study, conducted to identify interregional transmission solutions that improve reliability,
increase transfer capability, and reduce congestion along the southern seam (OK, AR, TX, LA),,” stated the draft report entitled “SPP-MISO 2024-25 Coordinated System Plan Study Report,” and released on Friday.
The study explained 70 solution proposals were considered while 46 stakeholder solutions were submitted and 24 alternative solutions were proposed.
“Based on initial results, three key corridors were identified within the study focus area in need of transmission support to address load growth and generation additions:
• Area A: Norther Arkansas – Oklahoma
• Area B: Texarkana / Southwest Arkansas
• Area C: Northwest Louisiana”
The two power grids are requesting feedback from stakeholders on the two combinations and plan to work with the states to consider any joint operating agreements or tariff enhancements to support interregional cost allocation.
The price tags on each of the proposals are in the one to nearly $4 billion range. One project called Core would cost nearly $1.3 billion while the other project, called Core+, would cost nearly $3.6 billion.
As reported by Utility Dive, the Core+ projects fix more MISO and tie‑line reliability issues and deliver the greatest 2034 congestion relief, especially in SPP, while providing “moderate” import capability gains, the grid operators said in the draft report.
The report on the proposals was presented last Friday to the SPP-MISO Interregional Planning Stakeholder Advisory Committee.