Azusa — United States of America

Azusa is a 3 MW hydro power plant in California, United States of America. It is operated by City of Pasadena - (CA). Based on its capacity (estimated), it can supply roughly 3.0k homes (estimated). It ranks #8053 of 10,884 United States of America power plants by installed capacity. Commissioned in 1949, it is around 77 years old — an older, legacy facility. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, hydro supplies about 5.3% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0006449.

Data provenance

Source of the capacity and fuel values:

capacity: Wikidata P2109; fuel: WRI GPPD

In context: how this plant compares

At 3 MW, Azusa is below the median hydro plant in United States of America (8 MW). Hydropower converts the energy of falling or flowing water into electricity; output depends on rainfall and reservoir level, and large dams also provide grid balancing and storage.

Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.

Key facts

Share of United States of America hydro capacity

less than 0.1% of 102,513 MW across 1,449 plants in this dataset

Age among peers

546 of 1,444 dated hydro plants in United States of America are older

Calculated from the capacity and generation records in this dataset (WRI Global Power Plant Database (CC BY 4.0)).

Reported generation trend

Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by City of Pasadena - (CA).

Local climate & thermal context

This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a warm-summer Mediterranean climate (Köppen Csb) — Northern Hemisphere, latitude 34.2°N — which shapes how much energy it can produce and how its output varies through the year.

Monthly mean temperature

Heating degree-days here run 67% below the median power plant in this dataset — a proxy for how much extra energy heated equipment must replace through its surfaces in winter.

Climate heat-demand index: 24/100 — this site sits in the bottom third of the power plants we cover by heating degree-days.

Climate normals: WorldClim 2.1 (1970–2000 monthly normals, 10 arc-min, CC BY 4.0); zone: Köppen-Geiger world climate classification (Kottek et al. 2006, 0.5° grid). Degree-days & heat-demand index computed by PowerAtlas — a modelled heat-demand proxy, not a measured site figure.

Site climate & environmental severity

This site sits in an aggressive, high-corrosion environment (estimated ISO 9223 class C5 — Very high), with marine salt corrosion the leading environmental stress.

Indicative estimate via the ISO 9223:2012 informative method (atmospheric corrosivity from temperature, time-of-wetness and airborne salinity), using WorldClim climate normals, the Köppen-Geiger class and coast distance. Indicative, not a measured corrosion rate.

How it compares & nearby plants

The #1045 largest hydro power plant of 1449 in United States of America by capacity.

United States of America has 1449 hydro power plants in this dataset, together about 102,513 MW of capacity.

Nearby power plants

• MolsonCoors Irwindale Brewery · Gas · 13.9 MW · California
• San Gabriel Hydro Project · Hydro · 5 MW · California
• San Dimas Wash Generating Station · Hydro · 1 MW · California
• San Dimas · Hydro · 9.9 MW · California
• Weymouth Solar Plant · Solar · 3 MW · California
• MM West Covina · Waste · 6.8 MW · California

Location

Coordinates 34.1548, -117.9093 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions