Old Faithful
Teton County, Wyoming · EIA plant ID 2196 · Operator: NorthWestern Energy DGGS
Nameplate2MWSummer 2 MW
Generators2in service
Net generation0GWh12 mo to Dec 2025
Capacity factor1%gas/coal/oil units, summer MW
Heat rate10,931Btu/kWhfossil units, electric fuel, HHV
First online1979Runs as rarely runs
Monthly net generation
EIA-923, all units at the plant. Net of station use; storage can go negative.
FinalPreliminary
Capacity factor by year
Net MWh ÷ (summer MW × hours), gas/coal/oil units. Each year uses that year's EIA-860 ratings; the hollow dot is the latest 12 months.
Heat rate by year
Electric fuel MMBtu × 1000 ÷ net MWh (Btu/kWh, HHV), fossil units only; CT + CA counted as one combined-cycle block.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2002 | 0 | 0.0% | — |
| 2003 | 0.3 | 1.8% | 16,193 |
| 2004 | 0 | 0.0% | — |
| 2006 | 0.2 | 1.4% | 12,008 |
| 2007 | 0.2 | 0.9% | 10,564 |
| 2008 | 0.2 | 1.4% | 10,492 |
| 2009 | 0.3 | 1.7% | 10,510 |
| 2010 | 0.2 | 1.0% | 10,720 |
| 2011 | 0.2 | 1.1% | 10,516 |
| 2012 | 0.3 | 1.6% | 10,505 |
| 2013 | 0.2 | 1.1% | 10,510 |
| 2014 | 0.1 | 0.7% | 10,508 |
| 2015 | 0.2 | 0.9% | 11,905 |
| 2016 | 0.1 | 0.4% | 10,449 |
| 2017 | 0.2 | 1.2% | 12,009 |
| 2018 | 0.2 | 0.9% | 10,522 |
| 2019 | 0.1 | 0.8% | 11,662 |
| 2020 | 0.1 | 0.5% | 15,282 |
| 2021 | 0.4 | 2.1% | 9,740 |
| 2022 | 0.3 | 1.7% | 10,913 |
| 2023 | 0.2 | 1.4% | 11,169 |
| 2024 | 0.3 | 1.6% | 11,059 |
| 2025 | 0.2 | 1.2% | 10,931 |
Generators
EIA-860 (annual) with EIA-860M updates through Sep 2026. EIA-923 reports generation by plant, prime mover and fuel, not by unit, so unit-level output isn't shown.
| Gen ID | Technology | Prime mover | Nameplate MW | Summer MW | Online | Status | Planned retirement | OEM / model |
|---|---|---|---|---|---|---|---|---|
| 1 | Petroleum Liquids | IC | 1 | 1 | Dec 1979 | Operating (Standby / backup) | — | coming soon |
| 2 | Petroleum Liquids | IC | 1 | 1 | Dec 1979 | Operating (Standby / backup) | — | coming soon |
Owner / operator
Operator: NorthWestern Energy DGGS. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| NorthWestern Energy DGGS | 100.0% | 2 MW |
Nearby plants
Within 80 km.
| Lake (WY) | 3 MW | 21.1 km |
| Island Park | 5 MW | 44.7 km |
| Falls River Hydro | 9 MW | 60.2 km |
| Ashton | 7 MW | 67.2 km |
| Felt | 7 MW | 69.9 km |
| Chester Diversion Hydroelectric Project | 4 MW | 76.8 km |