Oklahoma Gas & Electric (OG&E) plans to spend more than $7bn on transmission improvements by 2022, covering 25 new projects and upgrades including high priority projects and balanced portfolio projects identified in the Southwest Power Pool’s (SPP) transmission expansion plan (STEP) as well as regional reliability projects.
The integrated resource plan (IRP), which the utility issued Oct. 9, includes seven “major 345-kV transmission projects” that are underway and expected to be in service in 2014 or sooner. Two “high priority” projects, the 110-mile Thistle to Woodward District EHV line from the Thistle substation near Medicine Lodge, Kan., to Woodward, Okla., and the 122-mile Hitchland to Woodward EHV in northwest Oklahoma, are estimated to cost $151.5m and $188m respectively, and are expected to be placed in service in 2014.
Major projects include three “balanced portfolio” projects: the 36-mile Sooner to Cleveland line in central Oklahoma; the 100-mile Seminole to Muskogee project in the eastern part of the state; and the 250-mile Woodward District EHV line from Woodward, Okla., to the Oklahoma/Texas border and on to Tuco, Texas. Those projects, estimated to cost $4m, $175m, and $161.2m respectively, are expected to be placed in service in 2012, 2013, and 2014 respectively.
The two remaining major projects listed are the 106-mile Rose Hill, Kan., to Sooner, Okla., line, which is a regional reliability project, and the 120-mile Hugo to Sunnyside project, which is a transmission service project. Those projects, which cost $80m and $200m respectively according to TransmissionHub data, are currently in service.
In addition to the major projects listed, the utility has committed to 20 other projects, including building four new 345-kV lines and substations, reconductoring two 138-kV lines and one 161-kV line, and converting a 69-kV line to 161-kV.
Additional new 345-kV lines include the Gracemont to Elk City line, the Arcadia-Redbud project, the Woodward EHV to Mathewson line, and the Mathewson to Cimarron project. Those projects are estimated to cost $75.5m, $18m, $154m, and $53m. The Gracemont to Elk City line is projected to be in service in 2018, while the Arcadia-Redbud project has a projected in-service date of 2019. The Woodward EHV to Mathewson line and the Mathewson to Cimarron project are projected to be in service in 2021.
Reconductoring of the Ft. Smith – Colony 161-kV line, the Woodward District-FPL Switch 138-kV line and the Glass Mountain-Mooreland 138-kV line will cost $2.5m, $7.8m, and $16m respectively. The Ft. Smith – Colony line is expected to be completed by 2013, while the Woodward District-FPL Switch line and the Glass Mountain-Mooreland line are expected to be completed by 2022.
Converting the 69-kV Crescent-Cottonwood Creek line to 161-kV is expected to cost $5.4m and be completed in 2014.
Other projects include installing a 345-kV substation at the Canadian River facility; building a new Trans-Canada Pipeline substation; and upgrading the Van Buren Interconnect, the Bryant, and the Classen substations.
Additionally, the utility will install new transformers and capacitor banks and upgrade existing transformers at six substations.
More generation means more transmission
OG&E estimates it will need to invest $4.3m by 2023 to build the transmission needed to accommodate the planned addition of two 562-MW generating units at the Seminole generating station near Konawa, Okla.
In addition, the utility’s IRP acknowledges that additional transmission will also be needed to accommodate an additional 3,000 MW to 5,000 MW of wind generation. Wind generation within SPP’s area sometimes accounts for “upwards of 40% of area requirements,” the utility said, addng that the level of wind generation is beginning to have significant impacts on congestion.
“Only when there are major new transmission lines built in the western part of the system such as the balanced portfolio and [high] priority projects will this area see substantial congestion relief,” OG&E said.
However, the utility noted that the cost of those upgrades “has been allocated to the SPP members and, therefore, OG&E assumes no additional transmission improvement costs associated in its wind generation expansion analysis.”