Two Mississippi PSC orders issued involving 230-kV, 115-kV projects

The Public Service Commission (PSC) of Mississippi finds that the public convenience and necessity will be served by issuing a certificate of public convenience and necessity to the South Mississippi Electric Power Association (SMEPA) and Mississippi Power Company (MPC) that will authorize the construction, acquisition, extension, operation and maintenance of transmission and related facilities in Jasper County, Miss., according to a July 25 recommended order signed by a hearing examiner.

As noted in the recommended order, SMEPA and MPC filed the joint petition last November. MPC seeks authority to design, build, own, and operate a new 230-kV switching station, while SMEPA seeks authority to undertake the additional work required to upgrade its transmission line and interconnect its existing facilities with the new substation, the recommended order added.

The proposed facilities will be used in connection with MPC’s service to customers within its certificated area in the 23 counties of southern Mississippi. The recommended order also noted that no objections or protests to the granting of a certificate have been filed, no protestants have intervened, and no objections have been made to the granting and issuance of the recommended order.

The proposed project would be sited at the intersection of MPC’s Laurel East to Enterprise 230-kV line and SMEPA’s existing Missionary–Waynesboro 161-kV transmission line, which as part of the petitioners’ agreement, SMEPA will convert to 230-kV.

From SMEPA’s perspective, the proposed facilities are needed to establish a second transmission interconnection with MPC; provide voltage support to the nearby Missionary area, thereby improving transmission reliability in the area of the interconnection; to relieve loading on the existing 230/161-kV tie with PowerSouth in Waynesboro, Miss.; and increase the transfer capability between the SMEPA and MPC transmission systems.

From MPC’s perspective, the project will alleviate transmission line loadings, improve voltage profiles in the surrounding area, increase operational maintenance flexibility, and increase the load growth margin in the Meridian area, the recommended order added.

The estimated total cost of the project is about $10.7m, with MPC’s portion being $5.4m, which MPC plans to finance using a mix of debt and equity. SMEPA’s share of the project costs totals about $5.3m, the recommended order added, noting that SMEPA may fund the project using a combination of general funds, CFC, and/or CoBank loan funds and possible insured and guaranteed RUS loan funds. Additionally, SMEPA will receive open access transmission tariff credits from MPC in the amount of $1m, which will be credited to SMEPA transmission invoices over a period of two years.

Construction is expected to take about 18 months.

The recommended order further noted that exceptions to the recommended order may be filed with the PSC within a period of 15 days from the date that the order is issued, and if no exceptions are timely filed, then the recommended order is to become the PSC’s order.

Order on 115-kV project

As noted in a July 22 recommended order signed by PSC Commissioner Cecil Brown, SMEPA and Delta Electric Power Association (Delta) in February filed a joint petition seeking a certificate of public convenience and necessity authorizing SMEPA to build, maintain and operate a 115-kV electric transmission line and switching station in Sunflower County, Miss., and authorizing Delta to build, maintain and operate a 115:13.2-kV substation facility in Sunflower County, together with all the necessary switches, buses and related equipment and facilities.

The requested facilities are commonly referred to as the Steiner Project. The recommended order also noted that no objections or protests to the granting of a certificate have been filed, no protestants have intervened, and no objections have been made to the granting and issuance of the order.

SMEPA’s proposed 115-kV switching station will be located at a point adjacent to Entergy Mississippi’s existing 115-kV transmission line and just north of Hwy 442. Its estimated cost is $500,000, the recommended order said.

SMEPA estimates that about 0.2 miles of 115-kV transmission line may be required between the proposed switching station and the new Delta substation. The estimated cost of that line is $75,000.

The recommended order added that Delta’s new substation will be designed to use one 12/16/20 MVA transformer, built on a four-acre lot in the Steiner community. The estimated cost of the substation is $1.8m.

The facilities are expected to completed within 24 months after approval, the recommended order added.

The proposed electric transmission line, switching station and substation facilities purport to provide sufficient capacity and improve reliability and quality of service in Sunflower and Bolivar counties. The evidence submitted in the case indicates that that area has experienced an increase in demand in recent years due to significant irrigation growth.

The recommended order also said that it “finds that the public convenience and necessity will be served by issuing unto petitioners a certificate of public convenience and necessity authorizing them to acquire the necessary sites and rights-of-way, and to own, construct, install, maintain and operate the electric transmission line, switching station, and substation facilities.”

The recommended order further noted that the facilities are needed and required for Delta to have the power supply necessary to meet the present and immediately foreseeable needs of its members within its certificated area in Sunflower County, and for SMEPA to provide a reliable source of power from its transmission system to the new Delta delivery point.

Exceptions to the recommended order may be filed with the PSC within a period of 15 days from the date that the order is issued, and if no exceptions are timely filed, then the recommended order is to become the PSC’s order.

About Corina Rivera-Linares 3264 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 15 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at clinares@endeavorb2b.com.