Yanai is a 1,578 MW gas power station in Yamaguchi, Japan. It is operated by Chugoku. Based on its capacity (estimated), it can supply roughly 1.8 million homes (estimated). It ranks #56 of 692 Japan power plants by installed capacity. Commissioned in 1992, it is around 34 years old — long-established. Its modelled annual emissions are 2,347,100 t CO₂/yr (Climate TRACE), equivalent to about 547k cars driven for a year. In context, gas supplies about 32.8% 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 WRI1000658.
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
The public capacity above is the current source-record value. A 2026 tracker candidate lists 1,578 MW for Yanai power station, but it is not used as the public primary value until scope is verified (unit vs operating vs installed/project total).
Capacity claim grade: A2_GENERAL_REVIEW - recommended action: manual_source_check - confidence: medium_low. This follows a claim-based data model: value + scope + source + confidence, rather than silently overwriting records.
The capacity and/or fuel fields on this page include a source-backed provenance label from GEM, an official registry, Wikidata, OSM, or a cross-source match.
capacity: GEM tracker 2026 (location L100000405194); fuel: WRI source-record fuel
At 1,578 MW, Yanai is well above the median gas plant in Japan (847 MW). Technically it is described as CCGT; combined-cycle with a heat-recovery steam generator (HRSG). Gas plants burn natural gas either in open-cycle turbines for fast peaking, or in combined-cycle units that recover exhaust heat in an HRSG to reach roughly 55–62% efficiency — the cleanest-burning fossil option.
Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.
This facility's annual emissions are roughly equivalent to:
Equivalencies via US EPA Greenhouse Gas Equivalencies; modelled emissions from Climate TRACE.
Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).
Operated by Chugoku. All plants by this company →
This gas plant burns natural gas in a turbine — often in a combined-cycle setup — to generate electricity. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 34.0°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 28% 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: 39/100 — this site sits in the mid third of the power plants we cover by heating degree-days.
A gas turbine here also runs ~0% below its ISO (15°C) rating at this annual mean (typical CCGT curve, 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.
For a plant’s outdoor hardware — heat-recovery steam generators (HRSG), expansion joints, valves, flanges and their insulation — the local climate sets how fast unprotected steel and coatings degrade. This site sits in a corrosive environment (estimated ISO 9223 class C4 — High), with humidity / wetness the leading environmental stress.
Higher environmental severity is exactly where protective removable insulation pays back most: a sheltered micro-climate slows corrosion, UV and thermal-cycling damage and extends outdoor hardware service life. This is an indicative site-climate context — not a condition assessment of any specific plant or operator.
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.
The #17 largest gas power plant of 66 in Japan by capacity.
Japan has 66 gas power plants in this dataset, together about 74,949 MW of capacity.
Coordinates 33.953, 132.1248 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Yanai is a 1,578 MW source-record gas power plant in Yamaguchi, Japan, commissioned in 1992.
Its output is enough to supply roughly 1,777,278 homes (estimated).
Yanai is operated by Chugoku.
Yanai has modelled emissions of about 2,347,100 tonnes of CO₂ per year (Climate TRACE).
