Entergy’s (NYSE:ETR) Entergy Texas Inc., (ETI), in an April 7 application for a certificate of convenience and necessity filed with the Public Utility Commission (PUC) of Texas, said that it is proposing to build two new 230-kV substations and to install a new 230-kV transmission line between those substations to alleviate power flow limitations and low voltages in the Port Arthur area.
The proposed Garden 230-kV substation would be located on a new 43-acre site near Central Gardens, Texas, and would be built with three 230-kV breaker and a half bays. The three 230-kV breaker and half bays would include eight new 230-kV breakers, 17 230-kV disconnect switches, bus work, substation dead end and support structures, a new control house, relay panels, and control cables.
ETI also said that the new substation would provide for five transmission line positions. Two existing transmission lines – the McFadden Bend-China (Line 496) and Nederland-Mid County (Line 539), would be cut-in to the new Garden substation and installed into four of the new line positions. ETI added that the new Garden-Legend (Line TBD) 230-kV transmission line would be installed in the remaining line position.
The proposed Legend 230-kV substation would be located on a 16-acre site near Port Acres, Texas, and would be built with one 230-kV breaker and a half bay operated as a ring bus. The breaker and a half bay would include three new 230-kV breakers, 13 230-kV disconnect switches, bus work, substation dead end and support structures, a new control house, relay panels, and control cables. ETI added that the new substation would provide for three transmission line positions. One existing transmission line – the Port Acres Bulk-Keith Lake (Line 829) – would be cut-in to the new Legend substation and installed into two of the new line positions. ETI also said that the new Garden-Legend (Line TBD) 230-kV transmission line would be installed in the remaining line position.
Steel or concrete monopole structures were selected for the proposed Port Arthur Reliability 230-kV Transmission Line Project in Jefferson County, Texas, due to their relatively small footprint compared to H-frame structures (two poles) or four leg steel lattice towers, the company said, adding that they are also easier to engineer and are aesthetically more appealing to property owners than the other two alternatives.
ETI said that the project involves 10.4 miles to 15.4 miles of 125-feet-wide right of way (ROW), along with about 11.42 miles to 15.78 miles of circuit.
Most of the study area is in a rural setting with the exception of urban residential neighborhoods within the Central Gardens community in the northeastern portion of the study area and the Port Acres community situated in Port Arthur near the southern portion of the study area. ETI also said that most of the rural areas of the study area are predominantly flat topography, with a system of canals and levees, associated with agricultural uses. Overall, most of the study area consists of land use improvements associated with agriculture, residential and commercial structures, roadways, and various utility corridors, the company said.
ETI said that the Port Arthur area of its service territory encompasses 62 substations serving loads within ETI’s certificated area, including the cities and communities of Central Gardens, Groves, Nederland, Port Acres, Port Arthur, Port Neches, Sabine Pass and Viterbo.
Considering the present system topology, planned network resource additions, and planned transmission upgrades, ETI and the Midcontinent ISO have determined that the proposed 230-kV transmission line and substations would be necessary before the summer of 2020 in order to continue to provide adequate and reliable service to customers in the southeastern area of ETI’s service territory.
According to the estimated schedule, ROW and land acquisition – as well as engineering and design – would begin in March 2018, and be completed in February 2019; material and equipment procurement would begin in May 2018, and be completed in April 2019; construction of facilities would begin in July 2018, and be completed in May 2020; and the facilities would be energized in June 2020.
ETI also said that it retained Black & Veatch to prepare the route selection study and environmental assessment for the project.
Black & Veatch used a detailed evaluation process to independently recommend “Route 11” as the primary alternative route that Black & Veatch and ETI representatives believe best addresses certain requirements. ETI added that Route 11:
- Has the fourth lowest estimated cost at about $70.3m
- Is tied for third with Routes 8 and 9 for the most length of route utilizing existing transmission line ROW
- Is tied with Routes 1, 3, 5, 6, 7, 10, 12, 13, 14, and 16 for the fewest number of parks/recreational areas within 1,000 feet at zero
- Is tied for first with Routes 5, 9, 10, 12, 13, 14, 15, and 16 for the least estimated length in pineywoods small stream and riparian herbaceous wetland at zero
- Avoids the tidal marsh area west of Port Acres, which is environmentally sensitive, a habitat for waterfowl and migratory birds, and presents possible challenges by the Texas Parks and Wildlife Department and U.S. Army Corps of Engineers
Among other things, the company added that Route 11 has 60 habitable structures within 300 feet of the proposed route centerline, and 20 structures within 300 feet of the proposed route centerline not adjacent to existing lines.