Hays Energy Project
Vistra · Hays County · ERCOT
Hays Energy Facility is a four-block natural-gas combined-cycle station near San Marcos in Hays County, Texas. EIA's May 2026 inventory reports 989 MW of nameplate capacity, 931 MW of net summer capability, and 1,048 MW of net winter capability. ERCOT's September 2026 resource outlook separately lists the four HAYSEN resources at 988 MW installed and 844 MW of summer capability. Hays Energy, LLC is the registered owner and operator; Vistra identifies Hays in its Texas generation fleet.
Overview
Key fields
- EIA net summer
- 931 MW
May 2026 · four operating blocks
- EIA nameplate
- 989 MW
1,048 MW net winter capability
- ERCOT summer
- 844 MW
988 MW installed · Sep 2026
- 12-month generation
- 5.65 TWh
May 2025–Apr 2026 · EIA Form 923
- Capacity factor
- 69.27%
Current EIA net-summer denominator
- Resource stack
- 4 resources
HAYSEN_HAYSENG1 · HAYSEN_HAYSENG2 · HAYSEN_HAYSENG3
Profile
- Market mapping
- Four ERCOT South-zone resources mapped to HAYSEN1_2 and HAYSEN3_4.
- Capacity records
- EIA: 989 MW nameplate, 931 MW summer, 1,048 MW winter. ERCOT September 2026: 988 MW installed, 844 MW summer.
- Environmental record
- TCEQ Regulated Entity RN100211689; Federal Operating Permit and Acid Rain Permit O2079, effective through September 18, 2029.
Structured profile
- Owner / operator
- Hays Energy, LLC
Vistra generation subsidiary
- Settlement points
- HAYSEN1_2 · HAYSEN3_4
ERCOT Resource Node to Unit Mapping
- Commercial operation
- Apr–Aug 2002
Four block-specific operating dates
- TCEQ entity
- RN100211689
Federal Operating Permit O2079
Units and generators
Operating generator records and technology attributes reported through EIA-860.
| Generator | Capacity | Technology | Operation | Status |
|---|---|---|---|---|
| U1 | 241.7 MW 234 MW summer | Natural Gas Fired Combined Cycle Natural Gas · CS | May 2002 | Operating |
| U2 | 241.7 MW 232 MW summer | Natural Gas Fired Combined Cycle Natural Gas · CS | Apr 2002 | Operating |
| U3 | 252.8 MW 231 MW summer | Natural Gas Fired Combined Cycle Natural Gas · CS | Aug 2002 | Operating |
| U4 | 252.8 MW 234 MW summer | Natural Gas Fired Combined Cycle Natural Gas · CS | Aug 2002 | Operating |
Performance
Monthly EIA generation history and recent market-resource behavior where linked telemetry is available.
Peer context
- Technology capacity
- 989 MW
- National rank
- #97
- TX rank
- #13
Monthly generation
Download CSVMonthly generation is reported through EIA-923. Capacity factor uses the current EIA nameplate capacity and is shown only for complete calendar years.
ERCOT disclosed dispatch
4 ERCOT market resources · Gas turbine
Output by hourlocal time · 90 days through May 22, 2026
Latest disclosed outputhourly · 2 weeks ending May 22, 2026
Generation from ERCOT's 60-Day SCED Disclosure (≈60-day lag), summed over this site's market resources.
Grid and market context
Deterministic links to ERCOT market resources, price records, outage disclosures, queue records, and nearby infrastructure. Candidate joins remain labeled until corroborated.
Market registration
ERCOT public disclosuresOperating context
ERCOT market recordsNearby substations
HIFLD infrastructure inventoryCommercial, land, and environmental record
Source-backed project transactions, agreements, land records, permits, and environmental disclosures. Portfolio and adjacent-project facts remain explicitly scoped.
Land and environmental record
Related parties and identifiers
Parties, market resources, and identifiers tied to this asset, with owner, operator, developer, EPC, compliance provider, and interconnecting entity roles kept separate.
Relationship graph
Drag organizations to explore the network. Select a node to pin its details and available page link.
Parties and identifiers
| Relationship | Entity | Basis |
|---|---|---|
| Market resources | HAYSEN_HAYSENG1, HAYSEN_HAYSENG2, HAYSEN_HAYSENG3, HAYSEN_HAYSENG4 | Linked ERCOT resources. |
| Grid selection | plant:plant-55144 | Canonical asset page /ercot/assets/plant/hays-energy-project. |
Reporting portfolio
Portfolio membership follows the latest EIA-860 reporting entity. It does not imply ultimate ownership.
Timeline and sources
Project milestones and public references behind the asset profile.
Project timeline
- Block 2 entered serviceEIA May 202...
EIA reports April 2002 for generator U2; ERCOT reports April 19, 2002 for HAYSEN_HAYSENG2.
- Block 1 entered serviceEIA May 202...
EIA reports May 2002 for generator U1; ERCOT reports May 28, 2002 for HAYSEN_HAYSENG1.
- Blocks 3 and 4 entered serviceEIA May 202...
EIA reports August 2002 for generators U3 and U4; ERCOT reports August 16 and August 15 respectively.
- Federal operating permit renewedTCEQ Federa...
TCEQ renewed Federal Operating Permit and Acid Rain Permit O2079 through September 18, 2029.
- Latest disclosed generation interval
ERCOT SCED disclosure is delayed, so plant performance windows end at the latest disclosed interval.
Sources
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