Lewis & Clark

Coal power plant in Montana, United States of America. Approximate location 47.6785, -104.1566.

CoalMontanaUnited States of America

Lewis & Clark is a 69 MW coal power plant in Montana, United States of America. It is operated by Montana-Dakota Utilities Co. Based on reported annual generation of 264 GWh, it can supply roughly 75k homes. It ranks #3341 of 10,938 United States of America power plants by installed capacity. Commissioned in 1973, it is around 53 years old — an older, legacy facility. In context, coal supplies about 16.3% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).

69Legacy source-record capacity
264GWh reported / yr
75,285homes powered
1973commissioned (~53 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0006089.

Data status

Known data

FacilityLewis & Clark WRI
CountryUnited States of America · Montana WRI
Coordinates47.6785, -104.1566 WRI
FuelCoal WRI
MW installed capacity69 MW WRI source record; scope not independently normalised
OwnerMontana-Dakota Utilities Co WRI
Commissioned1973 WRI
GWh reported / yr264 GWh/yr WRI

Calculated from dataset

CO₂ emissions263,500 t CO₂/yr calculated
Capacity rank in country#3341 of 10938 calculated
Fuel-specific rank in country#717 of 802 calculated
Capacity vs country/fuel peers0.12× · 558 MW median · 802 peers calculated
Homes-powered equivalent75,285 calculated from reported generation
Climate7.1°C · HDD 4,256 derived from coordinates
Environmental severityC1 · 41/100 derived from coordinates

Not available

TechnologyNot available not in dataset
GWh reported / yrNot available not in dataset

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

Data provenance

The capacity and fuel fields on this page are source-record values from the upstream open dataset. They are useful for identification and ranking, but they have not been upgraded to a 2026 registry/GEM-location verified value.

capacity: WRI Global Power Plant Database source-record (legacy); fuel: WRI source-record fuel

In context: how this plant compares

At 69 MW, Lewis & Clark is below the median coal plant in United States of America (558 MW). Coal plants burn pulverised coal to raise high-pressure steam for a turbine; they run as baseload but are the most carbon-intensive mainstream source and the first targeted for retirement or efficiency retrofits.

Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.

Reported generation trend

2013: 299 GWh20132014: 290 GWh20142015: 222 GWh20152016: 273 GWh20162017: 230 GWh20172018: 243 GWh20182019: 264 GWh2019299 GWh

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

Owner

Operated by Montana-Dakota Utilities Co. All plants by this company →

Local climate & thermal context

This coal plant burns coal to raise high-pressure steam that spins a turbine-generator. It sits in a cold semi-arid steppe climate (Köppen BSk) — Northern Hemisphere, latitude 47.7°N — which shapes how much energy it can produce and how its output varies through the year.

7.1°Cannual mean temp
4,256heating degree-days (base 18°C)
312cooling degree-days (base 18°C)
660 melevation

Monthly mean temperature

J: -10 °CJF: -6 °CFM: 0 °CMA: 8 °CAM: 14 °CMJ: 19 °CJJ: 23 °CJA: 22 °CAS: 15 °CSO: 9 °CON: -1 °CND: -8 °CD23 °C

Heating degree-days here run 73% above 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: 87/100 — this site sits in the top 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 benign, low-corrosion environment (estimated ISO 9223 class C1 — Very low), with dust abrasion the leading environmental stress.

C1ISO 9223 corrosivity (indicative)
41/100environmental-severity index
33.2°Cseasonal temperature swing
660 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 #717 largest coal power plant of 802 in United States of America by capacity.

United States of America has 802 coal power plants in this dataset, together about 621,194 MW of capacity.

Nearby power plants

Location

Coordinates 47.6785, -104.1566 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions

What type of power plant is Lewis & Clark?

Lewis & Clark is a 69 MW source-record coal power plant in Montana, United States of America, commissioned in 1973.

How much electricity does Lewis & Clark generate?

Lewis & Clark generates about 264 GWh of electricity per year.

How many homes can Lewis & Clark power?

Its output is enough to supply roughly 75,285 homes.

Who operates Lewis & Clark?

Lewis & Clark is operated by Montana-Dakota Utilities Co.

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