Vacaville — United States of America
Solar power plant in California, United States of America. Approximate location 38.3994, -121.9603.
SolarCaliforniaUnited States of America
Vacaville is a 1 MW solar power plant in California, United States of America. It is operated by Janssen Pharmaceutical Co. Based on reported annual generation of 2 GWh, it can supply roughly 571 homes. It ranks #10835 of 10,884 United States of America power plants by installed capacity. Commissioned in 2007, it is around 19 years old — relatively modern. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, solar supplies about 8.6% 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 USA0059058.
Data status
Known data
Calculated from dataset
Not available
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
Capacity provenance
The public capacity above is the current source-record value. A 2026 tracker candidate lists 2 MW for Vacaville Hospital solar farm, but it is not used as the public primary value until scope is verified (unit vs operating vs installed/project total).
Data provenance
Source of the capacity and fuel values:
capacity: Wikidata P2109; fuel: WRI GPPD
In context: how this plant compares
At 1 MW, Vacaville is below the median solar plant in United States of America (3 MW). Solar PV converts sunlight directly into electricity with no moving parts or fuel; output varies by time of day and weather, so it pairs with storage or flexible backup.
Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.
Key facts
- Load factor
- 23%, from 2 GWh of reported generation; the median for 3185 solar plants in United States of America that report generation is 19%
- Generation trend
- 2 GWh in 2013 and 2 GWh in 2019 (+0%)
- Highest and lowest year
- 2013: 2 GWh; 2016: 0 GWh
- Share of United States of America solar capacity
- less than 0.1% of 38,093 MW across 3,283 plants in this dataset
- Age among peers
- 10 of 3,277 dated solar 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 Janssen Pharmaceutical Co.
Local climate & thermal context
This solar plant converts sunlight directly into electricity with photovoltaic panels. It sits in a hot-summer Mediterranean climate (Köppen Csa) — Northern Hemisphere, latitude 38.4°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 48% 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: 30/100 — this site sits in the bottom third of the power plants we cover by heating degree-days.
Solar PV loses ~0.35%/°C above 25°C cell temperature — roughly 0.0% at warm-season highs here (estimate).
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 a moderately corrosive environment (estimated ISO 9223 class C3 — Medium), with humidity / wetness 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 #3251 largest solar power plant of 3283 in United States of America by capacity.
United States of America has 3283 solar power plants in this dataset, together about 38,093 MW of capacity.
Nearby power plants
- Mariani Packing Vacaville Solar · Solar · 1 MW · California
- Genentech Vacaville Meter #1 · Solar · 6.1 MW · California
- Vacaville Hospital · Solar · 1.5 MW · California
- Vaca Dixon Battery Storage System · Storage · 2 MW · California
- CalPeak Power Vaca Dixon Peaker Plant · Gas · 60.5 MW · California
- Vaca Dixon Solar Station · Solar · 2 MW · California
Location
Coordinates 38.3994, -121.9603 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Frequently asked questions
What type of power plant is Vacaville?
Vacaville is a 1 MW solar power plant in California, United States of America, commissioned in 2007.
How much electricity does Vacaville generate?
Vacaville generates about 2 GWh of electricity per year.
Who operates Vacaville?
Vacaville is operated by Janssen Pharmaceutical Co.