Onahama 1 Solar Power Plant is a 12 MW solar power plant in Fukushima, Japan. It is operated by Onahama Solar LLC. Based on its capacity (estimated), it can supply roughly 5.1k homes (estimated). It ranks #533 of 692 Japan power plants by installed capacity. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, solar supplies about 9.8% of Japan's electricity; the national grid averages 477 gCO₂/kWh (32.7% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id WRI1026541.
Data status
Known data
Calculated from dataset
Not available
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
Data provenance
Capacity and fuel are the upstream open-dataset record, not yet matched to a 2026 registry or GEM entry.
capacity: WRI GPPD; fuel: WRI GPPD
In context: how this plant compares
At 12 MW, Onahama 1 Solar Power Plant is around the median solar plant in Japan (13 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
- Share of Japan solar capacity
- 0.2% of 5,680 MW across 324 plants in this dataset
Calculated from the capacity and generation records in this dataset (WRI Global Power Plant Database (CC BY 4.0)).
Capacity vs largest solar plants in Japan
Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).
Owner
Operated by Onahama Solar LLC.
Local climate & thermal context
This solar plant converts sunlight directly into electricity with photovoltaic panels. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 36.9°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 12% 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: 46/100 — this site sits in the mid 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 corrosive environment (estimated ISO 9223 class C4 — High), 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 #167 largest solar power plant of 324 in Japan by capacity.
Japan has 324 solar power plants in this dataset, together about 5,680 MW of capacity.
Nearby power plants
- Onahama power station · Coal · 400 MW · Fukushima Prefecture
- Iwaki Onahama Biomass power station · Biomass · 75 MW · Fukushima
- Onahama 2 Solar Power Plant · Solar · 6 MW · Fukushima
- Nakoso power station · Coal · 1,975 MW · Ibaraki
- Iwaki II · Solar · 22.6 MW · Fukushima
- Kureha Iwaki Factory power station · Coal · 45 MW · Ibaraki
Location
Coordinates 36.9442, 140.8939 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Frequently asked questions
What type of power plant is Onahama 1 Solar Power Plant?
Onahama 1 Solar Power Plant is a 12 MW solar power plant in Fukushima, Japan.
Who operates Onahama 1 Solar Power Plant?
Onahama 1 Solar Power Plant is operated by Onahama Solar LLC.