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Compare Generators Side-by-Side

Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.

  • Firman H08051
  • Powerhorse s15000d
  • Model H08051
    Model H08051

    Firman 8,000W Dual-Fuel Generator

    8000W
    Running
    74 dB
    Noise
    View details
  • Model s15000d
    Model s15000d

    Powerhorse 12,000W Dual-Fuel Generator

    12000W
    Running
    97 dB
    Noise
    View details
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
Generator Specifications Comparison
SpecificationFirman H08051Powerhorse s15000d
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Dual-Fuel
InverterNoNo
Parallel capableNoNo
RV readyYesNo
Running watts
8000 W
Winner: Winner: 12000 W
Starting watts
10000 W
Winner: Winner: 15000 W
Noise (lower limit)
Winner: Winner: 74 dB
97 dB
Weight
Winner: Winner: 212 lbs
348 lbs
Run time @50% load
Winner: Winner: 12 h
10 h
Run time @25% load
Not available—
Not available—
Fuel tank
8 gal
10.6 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
30.2 x 27.5 x 26.3
34.3 x 23.2 x 32.9
Electrical
Voltage (AC)
120/240
120/240V 60 Hz
Voltage (DC)
Not available—
12
GFCI outletsYesYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
25 %
<5% %
Engine
Engine
Firman Max-Pro Series OHV 4-stroke, cast iron sleeve
713 cc OHV V-Twin
Alternator
Not available—
Not available—
Starting system
Recoil, Electric
Electric
Warranty
Warranty
3 years
2 years
Power by fuel
GasolineNot available—Not available—
Running watts
8000 W
Not available—
Starting watts
10000 W
15000 W
Running amps (120V)
Not available—
Not available—
Running amps (240V)
Not available—
Not available—
Peak amps (120V)
Not available—
Not available—
Peak amps (240V)
Not available—
Not available—
Run time @50% load
12 h
Not available—
Run time @25% load
Not available—
Not available—
PropaneNot available—Not available—
Running watts
7250 W
10800 W
Starting watts
9050 W
13500 W
Running amps (120V)
Not available—
Not available—
Running amps (240V)
Not available—
Not available—
Peak amps (120V)
Not available—
Not available—
Peak amps (240V)
Not available—
Not available—
Run time @50% load
5 h
Not available—
Run time @25% load
Not available—
Not available—
Other
Data center
Not available—
Not available—
Indicators
false
true
Compliance
CARB, EPA
EPA, ANSI/PGMA G300-2023
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
Bonded to frame
Not available—
UPC
840876180518
840321764027
Core / High-priority specs
Running Watts (Gasoline)
8000
Not available—
Running Watts (Propane)
7250
10800
Starting Watts (Gasoline)
10000
15000
Starting Watts (Propane)
9050
13500
Runtime @ 50% Load (Gasoline)
12
Not available—
Runtime @ 50% Load (Propane)
5
Not available—
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R)
Not available—
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
OHV 4-stroke
OHV V-Twin
Engine Displacement
439
713
Cylinder Sleeve
Cast iron
Not available—
Runtime & fuel system
Runtime @ 50% Load (Gasoline)
12
Not available—
Runtime @ 50% Load (Propane)
5
Not available—
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection, CO monitoring
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringNoYes
Included equipment
Mobility Components
Wheel kit
Yes
Starting Components
Recoil, Electric
battery charging cables, battery
Fuel Connection Components
Propane hose
Not available—
Included Accessories
Oil, funnel, tool kit, propane hose, battery, and wheel kit
Funnel, tool kit, propane hose, battery charging cables, battery, and wheel kit
Warranty & identification
Commercial Warranty
3
Not available—
Part Number
Not available—
6075687
Additional specs
Summary
The Firman H08051 is an 8,000-watt dual-fuel generator built to power job sites, homes during outages, and RV setups. Running on gasoline, it delivers 8,000 watts continuously and 10,000 watts at startup, enough to run a refrigerator, microwave, and multiple power tools at once. Switch to propane and the output drops to 7,250 watts running and 9,050 watts starting, a trade-off for fuel flexibility and longer shelf life. The 439cc cast-iron engine is engineered for durability in commercial and residential use. At 212 pounds, this is a stationary or semi-portable unit, not a grab-and-go machine.
The Powerhorse s15000d is a dual-fuel portable generator delivering 15,000 surge watts and 12,000 rated watts, suitable for emergency home backup, EV charging, and demanding worksites.
  • Most Powerful
    Powerhorse s15000d
    12000W running
  • Quietest
    Firman H08051
    74 dB
  • Longest Runtime
    Firman H08051
    12h at 50% load
Where to buy
Prices can change. We update these automatically.
Firman H08051
Store links
No links yet.
Powerhorse s15000d
Store links
No links yet.
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