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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.

  • Cummins Onan P9500DF EFI
  • Powerhorse 2500i
  • Model Onan P9500DF EFI
    Model Onan P9500DF EFI

    Cummins 7,500W Dual-Fuel Generator

    7500W
    Running
    74 dB
    Noise
    View details
  • Model 2500i
    Model 2500i

    Powerhorse 1,800W Gas Generator

    1800W
    Running
    62 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
SpecificationCummins Onan P9500DF EFIPowerhorse 2500i
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Gasoline
InverterNoYes
Parallel capableNoYes
RV readyNoNo
Running watts
Winner: Winner: 7500 W
1800 W
Starting watts
Winner: Winner: 9500 W
2500 W
Noise (lower limit)
74 dB
Winner: Winner: 62 dB
Weight
211.6 lbs
Winner: Winner: 48.3 lbs
Run time @50% load
Winner: Winner: 9.6 h
9.5 h
Run time @25% load
14.4 h
10.5 h
Fuel tank
6.6 gal
1.2 gal
Fuel gaugeYesNo
Approx. dimensions (L × W × H)
27.3 x 20.6 x 22.6
20.4 x 12.5 x 18.3
Electrical
Voltage (AC)
120/240
120
Voltage (DC)
5
Not available—
GFCI outletsYesNo
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
23 %
3 %
Engine
Engine
420 cc OHV 4-stroke
80 cc OHV 4-stroke
Alternator
Not available—
Not available—
Starting system
Recoil, Electric, Remote
Recoil
Warranty
Warranty
3 years
2 years
Power by fuel
GasolineNot available—Not available—
Running watts
7500 W
Not available—
Starting watts
9500 W
2500 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
9.6 h
9.5 h
Run time @25% load
14.4 h
10.5 h
PropaneNot available—Not available—
Running watts
6750 W
Not available—
Starting watts
8550 W
Not available—
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
Not available—
Not available—
Run time @25% load
10.8 h
Not available—
Other
Data center
Not available—
Not available—
Indicators
false
true
Compliance
CARB, EPA, ANSI/PGMA G300-2023
EPA, ANSI/PGMA G300-2023
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
true
Floating
UPC
Not available—
840321763969
Core / High-priority specs
Running Watts (Gasoline)
7500
Not available—
Running Watts (Propane)
6750
Not available—
Starting Watts (Gasoline)
9500
2500
Starting Watts (Propane)
8550
Not available—
Runtime @ 50% Load (Gasoline)
9.6
9.5
Runtime @ 25% Load (Gasoline)
14.4
10.5
Runtime @ 25% Load (Propane)
10.8
Not available—
AC Outlet Types
2x Duplex 120V 20A (5-20R) GFCI; 1x 120/240V 30A (L14-30R)
1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
OHV 4-stroke
80 cc OHV 4-stroke
Engine Displacement
420
80
Engine Oil Type
SAE10W30
Not available—
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
14.4
10.5
Runtime @ 50% Load (Gasoline)
9.6
9.5
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection, CO monitoring
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringYesYes
Included equipment
Mobility Components
Yes
Not available—
Included Accessories
Oil, funnel, tool kit, key fob, propane hose, battery, and wheel kit
Funnel and tool kit
Warranty & identification
Commercial Warranty
3
2
Part Number
A075C509
Not available—
Additional specs
Summary
The Cummins Onan P9500DF EFI is a 7,500-watt dual-fuel generator built for users who need sustained power across multiple load types. On gasoline, it delivers 7,500 running watts and 9,500 peak watts. On propane, it drops to 6,750 running watts and 8,550 peak watts, which means propane users sacrifice roughly 10 percent of output but gain extended storage life and cleaner emissions. The electronic fuel injection engine handles high-altitude operation up to 13,123 feet without modification, making it viable for mountain jobsites, remote cabins, and RV camps where carbureted engines would struggle. At 211.6 pounds with an included wheel kit, this generator demands stationary placement or two-person handling, but the 6.6-gallon fuel tank stretches runtime to 14.4 hours at 25 percent load on gasoline. This is a workhorse for contractors, emergency backup, and off-grid scenarios where fuel flexibility and durability matter more than portability.
The Powerhorse 2500i is a portable inverter generator delivering 2,500 surge watts and 1,800 rated watts, featuring a quiet 52dB operation, CO shutdown function, and parallel-ready design for increased power needs.
  • Most Powerful
    Cummins Onan P9500DF EFI
    7500W running
  • Quietest
    Powerhorse 2500i
    62 dB
  • Longest Runtime
    Cummins Onan P9500DF EFI
    9.6h at 50% load
Where to buy
Prices can change. We update these automatically.
Cummins Onan P9500DF EFI
Store links
No links yet.
Powerhorse 2500i
Store links
No links yet.
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