# Clairemont Energy Storage

CAISO asset profile · https://askthegrid.com/assets/facilities/clairemont-energy-storage

## Current generation inventory

EIA plant 66266 · Inventory reporting month: 2026-08.

- batteries: 10 MW operating nameplate
- Capacity basis: operating_generator_nameplate_mw
- Source inventory: [EIA-860M workbook (preliminary)](https://www.eia.gov/electricity/data/eia860m/xls/august_generator2026.xlsx)
- Inventory retrieved: 2026-10-10T22:49:53.020309+00:00
- Filed coordinate (longitude, latitude): -117.1832, 32.825604
- OSM extract: 2026-10-09T20:21:04Z
- OSM mapped edit: 2026-01-05 14:44:54+00:00
- Map prepared: 2026-10-10T23:05:21.599793+00:00

Battery power (MW) and stored energy (MWh) are separate measures. Shared physical-site membership does not establish electrical connectivity, settlement or a common export limit.

## Reviewed overview

Clairemont Energy Storage is SDG&E’s battery microgrid beside Clairemont Substation in San Diego. The utility’s August 2024 financing report describes 9 MW / 29 MWh, while the August 2026 EIA inventory records 10 MW / 10 MWh and an operating start in March 2024. These are distinct reported capacity figures. The microgrid was designed to support local critical facilities during grid outages and participate in CAISO under normal conditions.

## Reviewed metrics

- **Nameplate capacity:** 10 MW — Canonical EIA plant baseline.
- **Registry anchor:** Plant 66266 — plant-66266
- **EIA nameplate energy:** 10 MWh — August 2026 EIA inventory; utility project-design energy is a separate reported basis.
- **Utility project rating:** 9 MW / 29 MWh — SDG&E August 2024 report.

## Facts

- **Technology:** Batteries
- **Operator:** San Diego Gas & Electric Company
- **Operating status:** Operating

## Related parties

- **Owner / operator:** San Diego Gas & Electric Company — utility owner and operator ([source](https://www.sdge.com/))
- **Construction contractor:** Morrow Meadows Corporation — Balance of Plant (BOP) contractor ([source](https://www.morrow-meadows.com/))
- **Regulator:** California Public Utilities Commission — regulatory authority ([source](https://www.cpuc.ca.gov/))
- **Market operator:** California Independent System Operator (CAISO) — wholesale market operator ([source](https://www.caiso.com/))

## Sources

- [docs.cpuc.ca.gov](https://docs.cpuc.ca.gov/PublishedDocs/Efile/G000/M238/K011/238011178.PDF) — docs.cpuc.ca.gov · authoritative — Source retained for exact-record publication review.
- [docs.cpuc.ca.gov](https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M428/K827/428827925.PDF) — docs.cpuc.ca.gov · authoritative — Source retained for exact-record publication review.
- [docs.cpuc.ca.gov](https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M490/K125/490125839.PDF) — docs.cpuc.ca.gov · authoritative — Source retained for exact-record publication review.
- [docs.cpuc.ca.gov](https://docs.cpuc.ca.gov/PublishedDocs/SupDoc/A2405007/7811/544870396.pdf) — docs.cpuc.ca.gov · authoritative — Source retained for exact-record publication review.
- [mbrweb.ferc.gov](https://mbrweb.ferc.gov/SearchlkpEIA/Index?page=756) — mbrweb.ferc.gov · authoritative — Source retained for exact-record publication review.
- [EIA August 2026 operating generator inventory](https://www.eia.gov/electricity/data/eia860m/) — www.eia.gov · authoritative — Exact asset capacity, commissioning month or approved design scope.
- [CPUC Resolution E-5219](https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M490/K125/490125839.PDF) — docs.cpuc.ca.gov · authoritative — Exact asset capacity, commissioning month or approved design scope.
- [SDG&E August 2024 Sustainable Financing Report](https://www.sempra.com/sites/default/files/2024-08/SDGE-Green-Bond-Report-080924-Final.pdf) — www.sempra.com · official_source — Exact asset capacity, commissioning month or approved design scope.

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Canonical page: https://askthegrid.com/assets/facilities/clairemont-energy-storage
Website: [San Diego Gas & Electric Company](https://www.sdge.com/)

Source: Ask the Grid — https://askthegrid.com/