Neil Simpson Ii

⛏ CoalElectric Utility130 MW capacity

23rd largest plant in Wyoming · 2103rd nationally

Neil Simpson Ii is a coal power plant in Wyoming with a nameplate capacity of 130 MW. It generates roughly 685.7k MWh per year — enough to power about 65,307 average U.S. homes.

Its capacity factor of 60% puts it in the middle range — running steadily but not full-time. At 2666 lb CO₂/MWh, its emission rate sits above the national grid average of roughly 800 lb/MWh.

PeakingMid-meritBaseload0%40%80%100%60%
Mid-merit — steady but not full-time

Month by month in 2024

100% capacity0Jan: 59.4k MWh (61% of capacity)JFeb: 55.2k MWh (63% of capacity)FMar: 58.0k MWh (60% of capacity)MApr: 51.9k MWh (55% of capacity)AMay: 21.9k MWh (23% of capacity)MJun: 50.4k MWh (54% of capacity)JJul: 51.7k MWh (53% of capacity)JAug: 55.5k MWh (57% of capacity)ASep: 48.7k MWh (52% of capacity)SOct: 51.7k MWh (53% of capacity)ONov: 46.8k MWh (50% of capacity)NDec: 56.6k MWh (59% of capacity)D

Ghost bars are each month's theoretical maximum (130 MW nameplate × hours in the month). Filled bars are actual net generation reported to EIA Form 923. The gap between them is capacity factor made visible.

Capacity130 MWnameplate
Annual Generation685.7k MWhEPA eGRID
Capacity Factor60%of theoretical max
Annual CO₂914.1kmetric tons

Location

Plant NameNeil Simpson Ii
OperatorBlack Hills Power, Inc.
CityGillette
CountyCampbell County
StateWyoming
ZIP82718
Coordinates44.28560, -105.38330

This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.

Natural GasCoal

Generators (2)

IDTechnologyFuelCapacityStatusOnline
2Conventional Steam CoalSubbituminous Coal90.0 MWOperating1995
GT1Natural Gas Fired Combustion TurbineNatural Gas40.0 MWOperating2000

Emissions (annual)

CO₂914.1k metric tons
SO₂413 metric tons
NOₓ676 metric tons
CO₂ Rate2666 lb/MWh
U.S. grid average800 lb/MWhNatural gas combined-cycle average900 lb/MWhCoal plant average2,100 lb/MWhThis plant2,666 lb/MWh

Annual totals and CO₂ rate reported by EPA eGRID for 2023. Reference averages are approximate U.S.-wide figures from the same dataset.

Grid context

NERC RegionWECC
Balancing AuthorityWestern Area Power Administration - Rocky Mountain Region

About Coal plants

Coal plants burn pulverized coal to boil water and spin steam turbines. They emit substantial CO₂, SO₂, and NOₓ along with mercury and particulate matter. Modern units include scrubbers and selective catalytic reduction; older units are increasingly being retired or converted to natural gas as economics shift.

Other plants in Campbell County

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