How big is Dion R Holm?

Dion R Holm reports 180.2 MW hydroelectric of operating nameplate capacity. These technology ratings do not establish a common export limit. Source: EIA Sep 2026.

What kind of plant is Dion R Holm?

Dion R Holm is a Conventional Hydroelectric facility in Tuolumne County, CA, participating in the CAISO market.

Where is Dion R Holm located?

Dion R Holm is in Tuolumne County, CA, inside the CAISO balancing area.

Who operates Dion R Holm?

Dion R Holm is operated by City & County of San Francisco - (CA) according to the EIA generator inventory. Reporting membership does not by itself establish ultimate ownership.

How much electricity does Dion R Holm generate?

Dion R Holm reported 552 GWh over the twelve months to 2026-07. Figures are net generation as filed to EIA-923.

Where does Dion R Holm connect to the grid?

Dion R Holm on the City & County of San Francisco system.

How does Dion R Holm compare to other plants?

By capacity, Dion R Holm ranks #77 of 1,356 operating plants of the same technology nationally. It ranks #10 of 210 in CA.

Dion R Holm — 180 MW hydro plant, Tuolumne County, CA

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Dion R Holm — 180 MW hydro plant, Tuolumne County, CA · Ask the Grid

Generation and physical site

EIA plant 380 · Inventory for Sep 2026.

Reported operating nameplate by technology

Hydroelectric: 180.2 MW

Operating generators only. Battery power is in MW; stored energy is in MWh. These ratings do not establish a shared export limit.

Generator records (2)

EIA generator status and nameplate capacity for Dion R Holm
Generator	Technology	Status	Power (MW)	Energy (MWh)
1	Conventional Hydroelectric	Operating	90.1	Unknown
2	Conventional Hydroelectric	Operating	90.1	Unknown

Physical map location · OpenStreetMap: 37.89662, -119.96858
Filed location · EIA: 37.89665, -119.96750

Sources and observation dates

Inventory source: EIA-860M workbook (preliminary)
EIA reporting month: Sep 2026
EIA retrieved: Oct 24, 2026
OSM extract: Oct 9, 2026
OSM last mapped edit: Dec 5, 2025
Map prepared: Oct 24, 2026
Field verification: Not reported

Reporting month describes the inventory. Retrieval and map preparation describe processing; an OSM edit does not establish an in-service date.

EIA source inventory

Units and generators

Current generator records and technology attributes reported through EIA-860.

Generator	Capacity	Technology	Operation	Status
1	90.1 MW 90.1 MW summer	Conventional Hydroelectric HY	Aug 1960	Operating
2	90.1 MW 90.1 MW summer	Conventional Hydroelectric HY	Aug 1960	Operating

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.

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AssetOwner / operatorContractor

Parties and identifiers

OrganizationRoleBasis

Reporting portfolio

EIA reporting entity

City & County of San Francisco - (CA)

Entity 16612

Operating portfolio

5 plants

1 states

Reported capacity

421.6 MW

Conventional Hydroelectric · Other Waste Biomass

Largest reported plants in this portfolio
Largest reported plants	Capacity	State
Dion R HolmCurrent	180.2 MW	CA
R C Kirkwood	132.8 MW	CA
Moccasin	103.6 MW	CA
Moccasin Low Head Hydro Project	2.9 MW	CA
SF Southeast Cogen Plant	2.1 MW	CA

Portfolio membership follows the latest EIA-860 reporting entity. It does not imply ultimate ownership.

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Overview

Overview

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Infrastructure record

Profile

Structured profile

Generation and physical site

Reported operating nameplate by technology

Mapped facility footprint

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Units and generators

Performance

Peer context

Monthly generation

Grid and market context

Nearby substations