HARQUAHALA GENERATING PROJECT
OperatingNatural Gas power plant
- Capacity
- 1,325 MW
- Primary fuel
- Natural Gas
- County
- Maricopa County
- Operator
- NEW HARQUAHALA GENERATING CO LLC
- Status
- Operating
- Commissioned
- 2004
- EIA plant ID
- 55372
- Generators
- 6
- Technology
- Natural Gas Fired Combined Cycle
- Net generation (2024)
- 3,343 GWh
- Capacity factor (2024, EIA nameplate)
- 30%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 33.4760, -113.1134
HARQUAHALA GENERATING PROJECT, a 1,325 MW Natural Gas power plant in Maricopa County, Arizona. One of 82 power plants tracked in Arizona on Bywatts.
How HARQUAHALA GENERATING PROJECT compares
With 1,325 MW of capacity, HARQUAHALA GENERATING PROJECT ranks 4th among the 71 operating power plants Bywatts maps in Arizona and 2nd of the 23 operating Natural Gas plants in the state. It accounts for about 8.2% of Arizona's operating Natural Gas capacity and 4.6% of all operating capacity in the state. Nationally it is the 40th-largest of the 1,185 operating Natural Gas plants in the database. Commissioned in 2004, it is newer than 52% of the 69 operating Arizona plants with a recorded commissioning year. It shares Maricopa County with 28 other operating plants, including PALO VERDE and SANTAN.
EIA-860 lists 6 generators at the site with 1,277 MW of nameplate capacity, all natural gas fired combined cycle technology. Net generation was 3,343 GWh in 2024 (a 30% capacity factor), up 25% from 2022.
Grid neighborhood
The nearest named substation is HARQUAHALA (500 kV), about 0.1 miles away; the closest transmission line found within 10 miles is a 500 kV line owned by ARIZONA PUBLIC SERVICE COMPANY, about 0.1 miles away. Another 9 operating power plants totaling 7,775 MW sit within 25 miles; the largest is PALO VERDE (4,209 MW, Nuclear).
Computed by Bywatts from HIFLD power plant, substation and transmission line records and EIA-860/923 survey data; distances are straight-line. Sources and methodology
Weather peril exposure
HARQUAHALA GENERATING PROJECT is a 1,325 MW natural gas power plant in Maricopa County, AZ, operated by NEW HARQUAHALA GENERATING CO LLC, commissioned in 2004. Maricopa County carries elevated modeled catastrophe exposure in the FEMA National Risk Index, scoring 2.7 of 5 at the 42nd national percentile. Wildfire is the leading peril, rated Relatively High by FEMA at the 85th percentile.
The Bywatts loss layer is calibrated to solar PV hardware, so it is not applied to a natural gas plant. The ratings below are the FEMA National Risk Index county hazard ratings for this location.
Maricopa County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Wildfire | Relatively High | 85th | 4.4 of 5 | <0.01 |
| Riverine flooding | Very High | 85th | 4.4 of 5 | 8.5 |
| Heat wave | Very High | 71st | 3.9 of 5 | 19.8 |
| Hail | Very High | 56th | 3.2 of 5 | 0.28 |
| Earthquake | Relatively Moderate | 49th | 3.0 of 5 | 0.01 |
| Strong wind | Very High | 19th | 1.8 of 5 | 1.4 |
| Tornado | Relatively Moderate | 7th | 1.3 of 5 | 0.57 |
| Lightning | Relatively High | 3rd | 1.1 of 5 | 32.3 |
| Winter weather | Relatively Low | 1st | 1.1 of 5 | 0.57 |
| Hurricane | Very Low | 0th | 1.0 of 5 | 0.01 |
Perils not assessed in Maricopa County
These perils carry no usable National Risk Index figure for this county, so they are excluded from the scoring rather than scored zero. A zero would claim the peril was assessed and found benign.
| Peril | Why it is not scored |
|---|---|
| Coastal flooding | FEMA rating is "Not Applicable" for this county |
| Ice storm | FEMA rating is "Not Applicable" for this county |
Model hail, wind and flood exposure for Maricopa County in the weather risk calculator
Ratings are the FEMA National Risk Index county hazard ratings; the peril score is a Bywatts transform of the FEMA national percentile. Full data sources and the solar vulnerability methodology are in the weather risk calculator.
Modeled estimate for screening and negotiation. Built from FEMA National Risk Index county hazard data and a solar vulnerability layer documented above. Not a quote, a binder, or actuarial advice, and not a substitute for a carrier's own model. Hazard data: FEMA National Risk Index December 2025, synced 2026-07-24. Resolution is county level, not site level.