By Tom Kleckner
MISO staff said Friday they will recommend three economic projects be included in the 2015 MISO Transmission Expansion Plan. The projects in Southern Indiana, East Texas and Central Arkansas have a projected cost of $281 million, including $85 million that PJM will pay for its share of the Indiana project.
Digaunto Chatterjee, MISO’s director of economic studies, told a special meeting of the Planning Advisory Committee that staff selected the Duff-Rockport-Coleman 345-kV project from among three under consideration near the RTO’s eastern seam with PJM in Southern Indiana.
Chatterjee said the MISO portion of the project — the Duff and Coleman substations and a 28.5-mile single circuit between them — has a benefit-cost ratio of 16.1 based on MISO’s estimated cost of $67.2 million.
The project, expected in service in 2021, should eliminate congestion around Newtonville and Coleman and provide slightly higher economic benefits than the Duff-Coleman alternative. MISO’s cost will be the same as the $67.2 million Duff-Coleman because PJM will pay $85.3 million for improvements that will allow it to eliminate the special protection scheme at its Rockport substation.
“It’s no difference to us whether it’s one project or two projects connecting with each other,” Chatterjee said.
The PJM portion of the project includes two 765/345-kV transformers in Rockport and a 14-mile double circuit between the substation and Duff-Coleman.
Reacting to concern that the PJM portion of the project could result in unexpected costs, Chatterjee said staff “will make it clear to the board MISO stakeholders don’t want any issues from the PJM side to keep us from going ahead with the project.”
“We fully expect Duff to Coleman will be connected to Rockport,” he told the PAC, “but we won’t let PJM’s processes interfere with our portion of the project.”
Chatterjee said he had received a commitment from PJM saying that will approve the project and pay the incremental costs. (See “AEP Agrees to Pay Share of Market Efficiency Project” in MISO Planning Advisory Committee Briefs.)
East Texas Project
MISO is also recommending two economic projects in its South region, including a two-part construction/rebuild that would ease congestion around an East Texas load pocket.
MISO recommends constructing a new 230-kV transmission line between the existing Lewis Creek substation and a new 345/230-kV substation that will cut into the Grimes-Crocket 345-kV line. In addition, it will rebuild the Newton Bulk-Leach 138-kV line.
Chatterjee said the project cleared the benefit-cost ratio under two different future generation scenarios, with a B/C of 1.5 assuming future generation inside the load pocket and a 2.88 B/C with generation added outside the pocket.
The project has an estimated cost of $122.5 million and a projected in-service date of 2021. It would ease congestion on three 138-kV lines.
Arkansas Project
The third project, rebuilding the Mabelvale-Bryant South 115-kV line, would reduce congestion in the southwest Little Rock area. It has a projected cost of $6.1 million and a weighted B/C ratio of 5.88, with an estimated 2020 in-service date.
Staff will accept stakeholder input on the three projects through Oct. 2. Previous feedback and MISO’s responses to the South projects have been posted in the Oct. 2 Market Congestion Planning Study meeting materials.
The PAC will consider MTEP 15 during its Oct. 14 meeting, before the plan goes on to the System Planning Committee in October and Board of Directors in December.
