Hiwassee Dam

Hydro power plant in North Carolina, United States of America. Approximate location 35.1509, -84.1775.

HydroNorth CarolinaUnited States of America

Hiwassee Dam is a 166 MW hydro power station in North Carolina, United States of America. It is operated by Tennessee Valley Authority. Based on reported annual generation of 342 GWh, it can supply roughly 98k homes. It ranks #2219 of 10,938 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).

166Source-backed capacity
342GWh reported / yr
97,771homes powered
1949commissioned (~77 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0002780.

Data status

Known data

FacilityHiwassee Dam WRI
CountryUnited States of America · North Carolina WRI
Coordinates35.1509, -84.1775 WRI
FuelHydro WRI
MW installed capacity166 MW WRI source record; scope not independently normalised
OwnerTennessee Valley Authority WRI
Commissioned1949 WRI
GWh reported / yr342 GWh/yr WRI

Calculated from dataset

Capacity rank in country#2219 of 10938 calculated
Fuel-specific rank in country#114 of 1449 calculated
Capacity vs country/fuel peers20.70× · 8 MW median · 1449 peers calculated
Homes-powered equivalent97,771 calculated from reported generation
Climate13.3°C · HDD 2,152 derived from coordinates
Environmental severityC3 · 33/100 derived from coordinates

Not available

TechnologyNot available not in dataset
GWh reported / yrNot available not in dataset
CO₂ emissionsnot applicable not applicable

Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.

Data provenance

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 L100000603820); fuel: WRI source-record fuel

In context: how this plant compares

At 166 MW, Hiwassee Dam is well above 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.

Reported generation trend

2013: 431 GWh20132014: 251 GWh20142015: 308 GWh20152016: 245 GWh20162017: 180 GWh20172018: 352 GWh20182019: 342 GWh2019431 GWh

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

Owner

Operated by Tennessee Valley Authority. All plants by this company →

Local climate & thermal context

This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 35.2°N — which shapes how much energy it can produce and how its output varies through the year.

13.3°Cannual mean temp
2,152heating degree-days (base 18°C)
467cooling degree-days (base 18°C)
545 melevation

Monthly mean temperature

J: 2 °CJF: 4 °CFM: 9 °CMA: 13 °CAM: 17 °CMJ: 21 °CJJ: 23 °CJA: 23 °CAS: 20 °CSO: 14 °CON: 9 °CND: 4 °CD23 °C

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: 45/100 — 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

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 moderately corrosive environment (estimated ISO 9223 class C3 — Medium), with humidity / wetness the leading environmental stress.

C3ISO 9223 corrosivity (indicative)
33/100environmental-severity index
20.8°Cseasonal temperature swing
450 kmdistance to coast

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.

How it compares & nearby plants

The #114 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

Location

Coordinates 35.1509, -84.1775 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions

What type of power plant is Hiwassee Dam?

Hiwassee Dam is a 166 MW source-record hydro power plant in North Carolina, United States of America, commissioned in 1949.

How much electricity does Hiwassee Dam generate?

Hiwassee Dam generates about 342 GWh of electricity per year.

How many homes can Hiwassee Dam power?

Its output is enough to supply roughly 97,771 homes.

Who operates Hiwassee Dam?

Hiwassee Dam is operated by Tennessee Valley Authority.

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