By Amanda Durish Cook

CARMEL, Ind. — Preliminary results of MISO and SPP’s 2016 coordinated system study are in, and the RTOs say one South Dakota project has potential even though it fails MISO’s $5 million interregional cost threshold.

Davey Lopez, MISO advisor of planning coordination and strategy, said the project — the Split Rock-Lawrence 115-kV circuit into Sioux Falls, S.D. — costs $4.56 million but is still a strong contender at a 4.79 benefit-cost ratio. The RTOs would split the benefit of the transmission project at 56% for MISO and 44% for SPP.

“This project still shows high potential to be an interregional project. … Both MISO and SPP are open to removing that hurdle,” Lopez said of MISO’s threshold. MISO won FERC approval to shed its $5 million cost minimum and 345-kV limit with PJM last year in favor of no cost floor and a 100-kV threshold. But the commission said the order did not apply to the MISO-SPP process. (See FERC Signals Bulk of NIPSCO Order Work Complete.)

The RTOs looked at seven needs for the coordinated study: two shared tie-lines, one MISO project and four SPP projects. Three of the seven possible projects are unlikely to move forward, MISO stakeholders learned at a March 15 Planning Advisory Committee meeting.

Three other projects passed joint operating agreement cost and benefit tests, but the RTOs still have reservations:

• The $8 million Lyon County 345/115-kV transformer in South Dakota has a 1.14 B/C ratio and could be split 8% to MISO and 92% SPP according to regional benefit. However, MISO and SPP say those preliminary results are “highly dependent” on solar expansion in the area and said more analysis is needed before recommendation.
• The $8.3 million Crosstown-Blue Valley 161-kV line in Missouri has a 3.34 B/C ratio and could be portioned 32% to MISO and 68% to SPP. SPP staff is currently evaluating whether its own solution could be more cost-effective, and MISO says that to pursue the project, it would have to revise its cost allocation process because the line is below 345 kV.
• The $25 million New Brookline-James River 345-kV line and new 345/161-kV James River transformer in Missouri has a 2.06 B/C ratio and could be divided 19% to MISO and 81% to SPP. But SPP is again examining its own regional solution and MISO is testing its own regional criteria because the project is located wholly outside of MISO and because MISO’s adjusted production cost is not in synch with SPP’s.

PAC Chair Cynthia Crane said the RTOs’ mismatched adjusted production cost calculations seem to be driving a lot of MISO’s cost allocation issues.

Lopez said both RTOs will make efforts in the future to align their adjusted production cost calculation. He also said the study’s sub-345-kV projects must be regionally approved on a case-by-case basis because of the 345-kV prerequisite.

The remaining three projects in the coordinated study either failed the 5% minimum regional cost benefit percentage or the $5 million project floor. In all three cases, either MISO or SPP will continue to evaluate the projects in their own regional processes.

More testing is needed to come up with a final list of projects, Lopez said.

The RTOs will finalize the coordinated study’s findings and publish a report in late April. At that time, the Interregional Planning Stakeholder Advisory Committee will vote on which recommended projects might proceed. The MISO side of the IPSAC vote will be conducted through the PAC.

MISO still maintains that the coordinated study will influence a longer-term joint study between the RTOs in 2017, although it’s unclear when they will work together on future interregional projects. Stakeholders learned earlier this month that a comprehensive MISO-SPP joint study is unlikely to occur in 2017. (See “Long Odds for 2nd MISO-SPP Joint Study,” SPP Briefs.)

The coordinated study was originally meant to focus on needs along SPP’s Integrated System in North Dakota, South Dakota and Iowa, and some stakeholders were doubtful that any projects would materialize. (See MISO-SPP Study Scope Finalized; Stakeholders Doubtful Projects will Result.) Last year, the IPSAC identified an initial list of high priority seams efforts for the study.