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  • Generac #7715 GP8000E
  • Genmax GM15000ET
  • Model #7715 GP8000E
    Model #7715 GP8000E

    Generac 8,000W Gas Generator

    8000W
    Running
    0 dB
    Noise
    View details
  • Model GM15000ET
    Model GM15000ET

    Genmax 13,000W Tri-Fuel Generator

    13000W
    Running
    76 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
SpecificationGenerac #7715 GP8000EGenmax GM15000ET
General
Product type
Generator
Generator
Fuel
Gasoline
Tri-Fuel
InverterNoNo
Parallel capableNoNo
RV readyNoYes
Running watts
8000 W
Winner: Winner: 13000 W
Starting watts
10000 W
Winner: Winner: 15000 W
Noise (lower limit)
0 dB
Winner: Winner: 76 dB
Weight
Winner: Winner: 198 lbs
242 lbs
Run time @50% load
10 h
Winner: Winner: 11 h
Run time @25% load
15 h
Not available
Fuel tank
7.9 gal
10.5 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
27.2 x 27 x 26.5
28 x 31.6 x 28.7
Electrical
Voltage (AC)
120/240
120/240
Voltage (DC)
Not available
12
GFCI outletsYesNo
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
Not available
23 %
Engine
Engine
Generac OHV 4-stroke, 420 cc
520 cc OHV 4-stroke
Alternator
Not available
Not available
Starting system
Recoil, Electric
Recoil, Electric, Remote
Warranty
Warranty
3 years
1 years
Power by fuel
GasolineNot availableNot available
Running watts
8000 W
11000 W
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
10 h
11 h
Run time @25% load
15 h
Not available
Natural gasNot availableNot available
Running watts
Not available
12000 W
Starting watts
Not available
12000 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
Not available
Not available
Run time @25% load
Not available
Not available
PropaneNot availableNot available
Running watts
Not available
13000 W
Starting watts
Not available
13000 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
Not available
Not available
Run time @25% load
Not available
Not available
Other
Data center
Not available
Not available
Indicators
false
true
Compliance
EPA, ANSI/PGMA G300-2023
EPA, ANSI/PGMA G300-2023
Security
Not available
Not available
Spark arrestorYesYes
Neutral
Bonded to frame
Floating
UPC
696471086225
760790901382
Core / High-priority specs
Running Watts (Gasoline)
8000
11000
Running Watts (Propane)
Not available
13000
Running Watts (Natural Gas)
Not available
12000
Starting Watts (Gasoline)
10000
15000
Starting Watts (Propane)
Not available
13000
Starting Watts (Natural Gas)
Not available
12000
Runtime @ 50% Load (Gasoline)
10
11
Runtime @ 25% Load (Gasoline)
15
Not available
AC Outlet Types
2x Duplex 120V 20A (5-20R) GFCI1x 120/240V 30A (L14-30R)
AC outlets3x Duplex 120V 20A (5-20R)1x 120/240V 30A (L14-30R)1x 120/240V 50A (14-50R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
Not available
OHV 4-stroke
Engine Displacement
420
520
Engine Oil Type
10W-30 / SAE 30
SAE 10W/30
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
15
Not available
Runtime @ 50% Load (Gasoline)
10
11
Safety & compliance
Overload Protection System
Low oil and overload protection, CO monitoring
Low oil and overload protection
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringYesYes
Included equipment
Starting Components
Oil, battery, and wheel kit
Recoil starter; Electric starter; Remote starter
Included Accessories
Oil, battery, and wheel kit
Oil, funnel, tool kit, key fob, battery charger, natural gas hose with NPT adapter, propane hose, cover, neutral bonding plug, battery, and wheel kit
Warranty & identification
Commercial Warranty
3
1
Part Number
7715, 7686
Not available
Additional specs
Summary
The Generac GP8000E is an 8,000-watt gasoline generator built for homeowners and contractors needing whole-house backup power or serious job site output. With 10,000 starting watts, it can handle the initial surge of air conditioners, well pumps, and power tools while running smaller loads continuously. The 7.9-gallon fuel tank delivers 15 hours at 25% load, meaning users can power essential devices through an entire night without refueling.
The Genmax GM15000ET is a 13,000-watt tri-fuel generator built for serious power demands. With 13,000 running watts and 15,000 starting watts, this unit can handle whole-house backup scenarios, including central air conditioning, refrigerators, well pumps, and multiple circuits running simultaneously. Because it runs on gasoline, propane, or natural gas, owners gain real flexibility during emergencies when one fuel source might be unavailable or during extended outages when tapping into a home natural gas line eliminates refueling trips entirely.
  • Most Powerful
    Genmax GM15000ET
    13000W running
  • Quietest
    Genmax GM15000ET
    76 dB
  • Longest Runtime
    Genmax GM15000ET
    11h at 50% load
Where to buy
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Generac #7715 GP8000E
Store links
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Genmax GM15000ET
Store links
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