Aioi is a 1,125 MW oil power station in Hyogo, Japan. It is operated by Kansai. Based on its capacity (estimated), it can supply roughly 845k homes (estimated). It ranks #88 of 692 Japan power plants by installed capacity. Commissioned in 1982, it is around 44 years old — long-established. Its modelled annual emissions are 892,440 t CO₂/yr (Climate TRACE), equivalent to about 208k cars driven for a year. In context, oil supplies about 2.5% 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 WRI1000657.
Data status
Known data
Modelled source 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 1,125 MW, Aioi is well above the median oil plant in Japan (1,000 MW). Technically it is described as Steam. Oil-fired plants burn heavy fuel oil or diesel, usually as peaking or backup capacity on islands and grids without gas pipelines; high fuel cost keeps their utilisation low.
Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.
~892,440 t CO₂/yr (modelled) — in everyday terms
This facility's annual emissions are roughly equivalent to:
Equivalencies via US EPA Greenhouse Gas Equivalencies; modelled emissions from Climate TRACE.
Key facts
- Share of Japan oil capacity
- 2.3% of 48,987 MW across 41 plants in this dataset
- Age among peers
- 20 of 28 dated oil plants in Japan are older
Calculated from the capacity and generation records in this dataset (WRI Global Power Plant Database (CC BY 4.0)).
Capacity vs largest oil plants in Japan
Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).
Owner
Operated by Kansai. All plants by this company →
Local climate & thermal context
This oil plant burns oil or diesel to drive turbines or reciprocating engines. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 34.8°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 26% 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: 40/100 — this site sits in the mid 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 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 #17 largest oil power plant of 41 in Japan by capacity.
Japan has 41 oil power plants in this dataset, together about 48,987 MW of capacity.
Nearby power plants
- Ako · Oil · 1,200 MW · Hyogo
- Nihonkaisui Ako power station · Other · 54.8 MW · Hyogo
- Ako Cement Plant power station · Coal · 102.5 MW · Hyōgo Prefecture
- Hirohata Works power station · Coal · 298 MW · Hyogo
- Himeji Daiichi · Gas · 1,442 MW · Hyogo
- Himeji Daini · Gas · 2,919 MW · Hyogo
Location
Coordinates 34.7742, 134.4568 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Frequently asked questions
What type of power plant is Aioi?
Aioi is a 1,125 MW oil power plant in Hyogo, Japan, commissioned in 1982.
Who operates Aioi?
Aioi is operated by Kansai.
How much CO₂ does Aioi emit?
Aioi has modelled emissions of about 892,440 tonnes of CO₂ per year (Climate TRACE).