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.
- Genmax GM15000ET
- NorthStar c15000s
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).
| Specification | Genmax GM15000ET | NorthStar c15000s |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Tri-Fuel | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | No |
| Running watts | 13000 W | Winner: Winner: 13500 W |
| Starting watts | Winner: Winner: 15000 W | Winner: Winner: 15000 W |
| Noise (lower limit) | 76 dB | Winner: Winner: 73 dB |
| Weight | Winner: Winner: 242 lbs | 390 lbs |
| Run time @50% load | Winner: Winner: 11 h | 10.6 h |
| Run time @25% load | Not available | Not available |
| Fuel tank | 10.5 gal | 12 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 28 x 31.6 x 28.7 | 43 x 36 x 35 |
| Electrical | ||
| Voltage (AC) | 120/240 | 120/240V 60 Hz |
| Voltage (DC) | 12 | Not available |
| GFCI outlets | No | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | 23 % | <5% % |
| Engine | ||
| Engine | 520 cc OHV 4-stroke | 688 cc Honda GX690 OHV V-Twin |
| Alternator | Not available | Not available |
| Starting system | Recoil, Electric, Remote | Electric |
| Warranty | ||
| Warranty | 1 years | 4 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 11000 W | 13500 W |
| Starting watts | 15000 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 | 11 h | 10.6 h |
| Run time @25% load | Not available | Not available |
| Natural gas | Not available | Not available |
| Running watts | 12000 W | Not available |
| Starting watts | 12000 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 | Not available | Not available |
| Propane | Not available | Not available |
| Running watts | 13000 W | Not available |
| Starting watts | 13000 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 | Not available | Not available |
| Other | ||
| Data center | Not available | Not available |
| Indicators | true | false |
| Compliance | EPA, ANSI/PGMA G300-2023 | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Floating | true |
| UPC | 760790901382 | 840321737861 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 11000 | 13500 |
| Running Watts (Propane) | 13000 | Not available |
| Running Watts (Natural Gas) | 12000 | Not available |
| Starting Watts (Gasoline) | 15000 | 15000 |
| Starting Watts (Propane) | 13000 | Not available |
| Starting Watts (Natural Gas) | 12000 | Not available |
| Runtime @ 50% Load (Gasoline) | 11 | 10.6 |
| AC Outlet Types | AC outlets3x Duplex 120V 20A (5-20R)1x 120/240V 30A (L14-30R)1x 120/240V 50A (14-50R) | 3x Duplex 120V 20A (5-20R) GFCI1x 120V 30A (L5-30R)1x 120/240V 30A (L14-30R)1x 120/240V 60A (14-60R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | OHV 4-stroke | Honda GX690 OHV V-Twin |
| Engine Displacement | 520 | 688 |
| Engine Oil Type | SAE 10W/30 | Not available |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 11 | 10.6 |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | Yes |
| Included equipment | ||
| Starting Components | Recoil starter; Electric starter; Remote starter | Not available |
| Included Accessories | Oil, funnel, tool kit, key fob, battery charger, natural gas hose with NPT adapter, propane hose, cover, neutral bonding plug, battery, and wheel kit | Funnel, battery, and wheel kit |
| Warranty & identification | ||
| Commercial Warranty | 1 | 4 |
| Additional specs | ||
| Summary | 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. | The NorthStar c15000s is a commercial-grade portable generator powered by a Honda GX690 OHV engine, delivering 15,000 surge watts and 13,500 rated watts. It features Quiet Armor Technology for reduced noise, a built-in battery charger/maintainer, and carbon monoxide detection with automatic shutdown for enhanced safety. |
- Most PowerfulNorthStar c15000s13500W running
- QuietestNorthStar c15000s73 dB
- Longest RuntimeGenmax GM15000ET11h at 50% load
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Genmax GM15000ET
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NorthStar c15000s
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