---
title: "Sigma Storage"
description: "Sigma Storage: 408 MW Battery project in Harris County, ERCOT HOUSTON developed by AES Distributed Energy, Inc. Currently Construction; build-chance 64%. Independent ERCOT queue tracking by Matt Prusak."
canonical: "https://www.ercotqueue.com/project/23INR0126"
markdown: "https://www.ercotqueue.com/project/23INR0126.md"
resource_type: "project"
source_report: "July 2026"
generated_at: "2026-08-07T17:27:53.695Z"
license: "https://creativecommons.org/licenses/by/4.0/"
---

# Sigma Storage

Sigma Storage is an ERCOT generation interconnection record identified by INR 23INR0126.

## Current reported project fields

| Field | Value |
| --- | --- |
| INR | 23INR0126 |
| Developer | [AES Distributed Energy, Inc](https://www.ercotqueue.com/developer/aes-distributed-energy-inc.md) |
| Fuel / technology | Battery / BA |
| Capacity | 408.4 MW |
| County | Harris County |
| ERCOT zone | HOUSTON |
| Point of interconnection | 40460 Deepwater 138kV |
| Projected commercial-operation date | 2029-10-01 |
| Reported status | SS Completed, FIS Started, No IA |
| Funnel stage | Construction |

County is the public geographic precision used by ERCOTQueue. Map symbols are county-level evidence and are not exact project coordinates.

## Independently derived Build Chance

| Measure | Value |
| --- | ---: |
| Validation-selected Build Chance | 64% |
| P05 | 46% |
| P50 | 65% |
| P95 | 83% |

### Score factors

| Factor | Percentage-point contribution |
| --- | ---: |
| Stage base rate | +76.9 pp |
| Fuel adjustment | -2.6 pp |
| Developer-history adjustment | 0.0 pp |
| Stage-velocity adjustment | 0.0 pp |
| COD-slippage adjustment | -10.0 pp |
| FIS-progress adjustment | 0.0 pp |
| Capacity adjustment | +0.1 pp |

These factors are ERCOTQueue derivations. The displayed probability is not an ERCOT forecast or an official project status.

## Reported milestones

| Milestone | Date |
| --- | --- |
| screening started | 2021-05-11 |
| screening complete | 2021-07-30 |
| fis requested | 2022-02-04 |
| construction start | 2028-05-01 |
| construction end | 2029-05-01 |

## Observed monthly history

- First seen: 2022-02
- Last seen: 2026-07
- Appearances: 54
- Score-series basis: Monthly points use the as-of seven-factor raw model on the validation-selected raw scale because the current isotonic candidate did not pass the project-purged application guard. The final point is anchored to the published current project score. The series shows trajectory, not a previously published frozen forecast.

The 30 most recent observed changes are shown below. The public JSON contains the complete history.

| Report month | Change | Detail |
| --- | --- | --- |
| 2025-08 | Projected COD | 2026-05-15 to 2029-10-01 (+41 months) |
| 2025-08 | Funnel stage | No IA to Construction |
| 2024-02 | Projected COD | 2024-12-31 to 2026-05-15 (+17 months) |
| 2022-02 | Funnel stage | First observation to No IA |

Complete project-history JSON: [https://www.ercotqueue.com/data/project_history/23INR0126.json](https://www.ercotqueue.com/data/project_history/23INR0126.json)

## Field provenance

- Reported fields: INR, name, developer, capacity, fuel, county, zone, point of interconnection, projected COD, status, and dated milestones.
- Derived fields: funnel stage, COD-delay indicators, Build Chance, factor contributions, and uncertainty range.
- Current project dataset: [https://www.ercotqueue.com/data/projects.json](https://www.ercotqueue.com/data/projects.json)
- Current flat CSV: [https://www.ercotqueue.com/data/projects.csv](https://www.ercotqueue.com/data/projects.csv)

## Source, citation, and reuse

- Human-readable page: [Sigma Storage](https://www.ercotqueue.com/project/23INR0126)
- Markdown representation: [https://www.ercotqueue.com/project/23INR0126.md](https://www.ercotqueue.com/project/23INR0126.md)
- Source report: July 2026
- Site refresh: August 2026
- Methodology: [ERCOTQueue methodology](https://www.ercotqueue.com/methodology)
- License: [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)
- Source data (application/json): [https://www.ercotqueue.com/data/projects.json](https://www.ercotqueue.com/data/projects.json)

ERCOTQueue distinguishes reported source fields from independently derived analysis. Queue capacity records development and interconnection activity; it does not establish financing, construction, or commercial operation. Build Chance is a research signal, not a guarantee or investment recommendation.