Oncor submitted the Treadway 138-kV switch and Expanse to Tredway 138-kV second circuit project in September last year.
The project is a tier one project with an estimated cost of $119,030,000 and does not require CCN.
Its in-service date is expected to be in December this year, targeting post-contingency thermal overloads and voltage violations on the Vealmoor to Buzzard Draw to Expanse 138-kV transmission line.
ERCOT has provided updates and conducted independent reviews.
The study area includes Far West regions, focusing on Martin, Howard, and Borden Counties.
Study assumptions included the 2023 RTP 2026 summer planning case, with an addition of 515 megawatts confirmed load to the study base case.
Three main options were evaluated: Oncor's proposed project (Option 1), an ERCOT alternative (Option 3), and another ERCOT option (Option 5).
Option 1 includes various construction and reconfiguration measures for the Treadway 138-kV circuits.
Option 3 proposes creating a new Red Salt 345-kV substation and building new transmission lines.
A planned maintenance outage analysis was conducted with no thermal or voltage violations under options.
Additional assessments included long-term load-serving capability, cost estimates, and feasibility assessments.
Option 1 was ultimately selected as it addresses project needs, improves long-term load serving capability, and has the highest ability to serve future loads without requiring CCN.
ERCOT recommended Option 1 with estimated costs of $119,030,000; option’s final approval will occur across various stages, seeking board endorsement by June.
No additional SSR adverse impacts were identified.
Clarifications were provided on the study assumptions and the historical reference case used (2023 RTP case) without further project additions from 2024 updates.
▶️4 - EIR Status Update – Baytown Area Load Addition Project
Oncor has submitted the Delaware Basin Stage 5 project for RPG review, with an estimated cost of $744,600,000 and an in-service date of December 2029.
The project addresses reliability issues due to load growth in the oil and gas sectors in the Delaware Basin area.
WETT submitted an alternative option with a portion estimated to cost $305.5 million, offering potential savings of $67,000,000 with an in-service date of December 2028 for WETT's portion.
ERCOT is conducting a single EIR by combining both project plans for evaluation.
Both projects have no identified reliability issues and meet ERCOT and NERC reliability criteria based on initial reliability analyses.
Oncor's option provides more significant incremental load serving capability and has a lower estimated cost compared to WETT's option.
Oncor's total estimated cost is approximately $868,400,000, while WETT's projected total cost is $907,700,000.
Both options are feasible, but Oncor's option is preferred due to lower cost, less CCN mileage, and improved load growth capability.
ERCOT will continue to evaluate the preferred Oncor option and provide updates in future meetings with a final recommendation expected in Q2 2025.
Recap of the Southwest Houston 345-kV reliability project submitted for RPG review October 2024.
Project cost estimated at $569,300,000; anticipated in-service by summer 2028.
Project aims to address thermal overloads observed by Centerpoint in 2023 RTP.
ERCOT's independent review of the project is ongoing.
Preliminary study results showed no unsolved power flow or voltage issues for various contingencies.
Speaker: Wes Woitt from CenterPoint
Project submitted based on 2023 RTP results identifying certain circuits as reliability needs due to historical congestion.
Request for ERCOT to explain changes affecting project necessity from 2023 to present.
Speaker: Robert Golen from ERCOT
Explained changes from 2023 RTP due to several projects relieving constraints and optimizing dispatch in the Houston area.
Current studies show high flows but no reliability violations.
Speaker: Craig Wolf with RES
Inquired about loads updated in 2024 RTP and the decision to resubmit the project as an economic evaluation.
Received answers on confirmed loads added and potential economic resubmission consideration.
Speaker: Raja Kakarla from CenterPoint
Requested ERCOT report detail on generation redispatch for thermal overload mitigation.
Speaker: Andrew Hamann from LCRA
Asked about generator redispatch process and how it relates to planning criteria.
Clarification on renewable dispatch flexibility and compatibility with deliverability criteria was provided.
Speaker: Kevin Hansen from Invenergy
Inquired about the Wharton GTC impact, with ERCOT clarifying there was no direct examination of this impact for the project.
Main Outcome: ERCOT will not recommend a project for RPG submission due to lack of identified reliability needs. However, discussions indicated potential for resubmission as an economic project, and ERCOT committed to detailing their findings and dispatch scenarios in the EIR report.
▶️7 - EIR Status Update – Aransas Pass to Rincon 69-kV Line Rebuild Project
The project is a Tier 2 with an estimated cost of $33,000,000 requiring a CCN, and is expected to be in service by June 2026.
It addresses post contingency thermal overloads in San Patricio County.
AEP and ERCOT presented the project overview and scope at the January RPG meeting.
The project is focused on areas north of the Corpus Christi Bay, particularly Rincon, Gregory, and Aransas Pass.
Base case analysis showed no violations from P1 to P7 contingencies.
AEP identified thermal overloads from Gregory to Aransas Pass, matching ERCOT’s findings.
Option 1 from AEP will rebuild the existing Aransas Pass to Gregory 69-kV position line, making it 138-kV capable, with emergency and normal ratings of 239 MVA over an 8.5 mile distance.
Option 1 includes rebuilding the Gregory to Rincon line and associating equipment, with similar rating over 0.03 miles.
ERCOT’s Option 2 includes additional Gregory to Gibbs 138 kV line and transformer with emergency ratings of 339 MVA over 0.36 miles.
Option 3 proposes a double circuit line from Ingleside Dupont switch to Ingleside 138-kV with ratings of 478 MVA over 3.25 miles.
No violations were observed during the N-1, G-1+N-1, X-1+N-1 analyses.
Future objectives include long-term load serving capabilities and congestion analysis with updates in future RPG meetings leading to a final recommendation in Q2 2025.
No questions were raised during the meeting.
▶️8 - EIR Status Update – Hartring to Upland 138-kV Line and Benedum Autotransformer Addition Project
Oncor and LCRA presented a joint project for a 138-kV line and autotransformer addition for RPG review, estimated cost is $94 million with completion contingent on the 22RPG010 project.
Project aims to address post-contingent thermal overloads and voltage violations due to oil and gas industry growth.
ERCOT is currently conducting an independent review of this project.
Various voltage violations in Upton and Reagan County and a thermal violation observed.
The proposed project involves reconfiguring existing substations and constructing new transmission lines and transformers with associated upgrades needed.
Reliability analysis conducted showing various voltage violations, thermal overloads, and unsolved power flows under different contingency categories.
David Herring from Bryan Texas Utilities (BTU) presented on the RELLIS campus reliability project.
The Texas A&M University System RELLIS campus in Bryan is projected to reach 377 megawatts by 2030 due to data centers, semiconductor research, and national defense research.
Studies show thermal and voltage violations at projected 2030 load levels, indicating a need for larger-scale projects.
BTU modeled smaller-scale upgrades including additional 138-kV lines and capacitors, but these were inadequate for projecting 2030 levels.
Larger project alternatives considered include upgrades to tie line capacities and new import paths.
Project Alternative 11 was recommended by BTU for being the most cost-effective and improving system reliability, introducing a new 345-kV source for potential future expansion.
The proposed project involves constructing new 345-kV and 138-kV lines, expanding substations, and installing transformers and capacitors.
Total cost estimated at $271.5 million, with a four-year completion timeline.
Comments suggest concerns about possible congestion due to interconnected 345-kV and 138-kV systems, though initial studies did not predict significant issues.
After addressing a question from Austin Energy, no further questions were raised in the meeting.
▶️10 - ERCOT Independent Review Scope: Texas A&M University System RELLIS Campus Reliability Project
Presentation by Ying Li from ERCOT planning, discussing the independent review study scope from the BTU Texas A&M University System RELLIS Campus reliability project.
Ying Li skipped the introduction as David already covered it.
There are numerous reliability violations in the BTU system as shown in a map.
BTU proposed the project for addressing the violations.
Study assumptions include using 2024 RTP base case and 2030 case (summer peak and maintenance).
Study regions focus on the east weather zone with transmission elements in Brazos and surrounding counties.
New transmission projects as per February 2025 TPIT report included in study base case; placeholders from 2024 RTP related to RPG removed for need analysis.
New generation projects meeting Planning Guide 6.9(1) conditions as per February 2025 GIS report will be added.
Load and reserves will be consistent with 2024 RTP; no load scale down needed for a newly confirmed load of about 378 MW by 2030.
Contingency plans include studying specified units and transformers; conduct needed analysis and project evaluation.
Next steps involve providing status updates at future RPG meetings and final recommendations planned for the three of this year.
No questions or comments from the attendees at the end of the presentation.
AEP representative inquired about RTP scope assumptions for this year; no definitive answer given.
Pushkar Chhajed inquired about load forecast timing; expected around April but not confirmed.
