Mormon Flat
Maricopa County, Arizona · EIA plant ID 148 · Operator: Salt River Project
Nameplate64MWSummer 69 MW
Generators2in service
Net generation34GWh12 mo to Aug 2026
Capacity factor1%hydro units, summer MW
Heat rate—thermal plants only
First online1926
The 12-month figures include preliminary EIA-923 months, which EIA revises. Final data runs through Dec 2025.
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), hydro 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.
Heat rate applies to fuel-burning (thermal) units only.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2001 | 116.7 | 19.7% | — |
| 2002 | 61.8 | 26.3% | — |
| 2003 | 101.5 | 12.9% | — |
| 2004 | -7.2 | 11.1% | — |
| 2005 | 27.2 | 10.1% | — |
| 2006 | 47.1 | 12.1% | — |
| 2007 | 35.5 | 8.4% | — |
| 2008 | 23.5 | 7.4% | — |
| 2009 | 58.9 | 14.2% | — |
| 2010 | 76.6 | 18.0% | — |
| 2011 | 36.1 | 10.5% | — |
| 2012 | 35.5 | 20.3% | — |
| 2013 | 13.1 | 17.0% | — |
| 2014 | 5.2 | 4.1% | — |
| 2015 | 8 | 7.0% | — |
| 2016 | 22.3 | 10.2% | — |
| 2017 | 7.4 | 9.2% | — |
| 2018 | 17.2 | 11.9% | — |
| 2019 | 25.4 | 1.4% | — |
| 2020 | 28.9 | 3.0% | — |
| 2021 | 38.2 | 1.7% | — |
| 2022 | 38.7 | 2.2% | — |
| 2023 | 67.8 | 17.3% | — |
| 2024 | 54.3 | 23.1% | — |
| 2025 | 45.7 | 15.4% | — |
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 |
|---|---|---|---|---|---|---|---|---|
| MF1 | Conventional Hydroelectric | HY | 9.2 | 11.5 | May 1926 | Operating | — | coming soon |
| MF2 | Hydroelectric Pumped Storage | PS | 54.3 | 57.3 | Jun 1971 | Operating | — | coming soon |
Owner / operator
Operator: Salt River Project. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Salt River Project | 100.0% | 64 MW |
Nearby plants
Within 80 km.
| Stewart Mountain | 13 MW | 8.7 km |
| Horse Mesa | 131 MW | 10.1 km |
| Pediment BESS I | 250 MW | 26.5 km |
| Mesa Carport PV | 5 MW | 27.3 km |
| Roosevelt | 36 MW | 29.1 km |
| South Consolidated | 1 MW | 32.8 km |