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- Generac #8917 GP18000EFI
- Powerhorse s27000d
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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 | Generac #8917 GP18000EFI | Powerhorse s27000d |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Dual-Fuel |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | No |
| Running watts | Winner: Winner: 18000 W | Winner: Winner: 18000 W |
| Starting watts | 22500 W | Winner: Winner: 27000 W |
| Noise (lower limit) | 0 dB | Winner: Winner: 97 dB |
| Weight | Winner: Winner: 442.8 lbs | 557 lbs |
| Run time @50% load | Winner: Winner: 9 h | 8 h |
| Run time @25% load | Not available | Not available |
| Fuel tank | 14.2 gal | 17.17 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 58.5 x 30.9 x 36.5 | 38 x 25.5 x 33.6 |
| Electrical | ||
| Voltage (AC) | 120/240 | 120/240 |
| Voltage (DC) | Not available | 12 |
| GFCI outlets | Yes | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | <5% % | <5% % |
| Engine | ||
| Engine | Generac G-Force OVHI 4-stroke | 999 cc OHV V-Twin |
| Alternator | Not available | Not available |
| Starting system | Electric | Electric |
| Warranty | ||
| Warranty | 3 years | 2 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 18000 W | 18000 W |
| Starting watts | 22500 W | 27000 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 h | 8 h |
| Run time @25% load | Not available | Not available |
| Propane | Not available | Not available |
| Running watts | Not available | 16200 W |
| Starting watts | Not available | 24300 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 | true | false |
| Compliance | CARB, EPA | EPA, ANSI/PGMA G300-2023 |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Bonded to Frame | true |
| UPC | 696471101324 | 840321763976 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 18000 | 18000 |
| Running Watts (Propane) | Not available | 16200 |
| Starting Watts (Gasoline) | 22500 | 27000 |
| Starting Watts (Propane) | Not available | 24300 |
| Runtime @ 50% Load (Gasoline) | 9 | 8 |
| AC Outlet Types | 120/240V 50A (NEMA 14-50R), 120V 20A GFCI Duplex (NEMA 5-20R), 120V 30A Locking (NEMA L5-30R), 120/240V 30A Locking (NEMA L14-30R) | 2x Duplex 120V 20A (5-20R) GFCI2x 120V 30A (L5-30R)1x 120/240V 30A (L14-30R)1x 120/240V 50A (14-50R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | Generac G-Force OVHI 4-stroke | OHV V-Twin |
| Engine Displacement | 816 | 999 |
| Engine Oil Type | 10W-30 / SAE30 | Not available |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 9 | 8 |
| Controls & display | ||
| Display Type | Hour Meter | Not available |
| Safety & compliance | ||
| Overload Protection System | Not available | Low oil and overload protection, CO monitoring |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | Yes |
| Included equipment | ||
| Mobility Components | 12" Never-flat Wheels, Folding Locking Handle | Not available |
| Starting Components | Electric Start, Battery Included | Not available |
| Included Accessories | Battery included | Funnel, tool kit, propane hose, battery charging cables, battery, and wheel kit |
| Warranty & identification | ||
| Residential Warranty | 3 | 2 |
| Commercial Warranty | 2 | 2 |
| Part Number | 8917-0 | Not available |
| Additional specs | ||
| Summary | The Generac GP18000EFI is an 18,000 watt gasoline generator built for whole house backup and demanding job sites. With 22,500 peak watts, it can run central air conditioning, well pumps, electric ranges, and full household loads simultaneously. This is a stationary power solution for users who need utility replacement capacity. | The Powerhorse s27000d is a robust dual-fuel generator offering 27,000 surge watts and 18,000 rated watts, suitable for both professional and home backup power needs. |
- Most PowerfulGenerac #8917 GP18000EFI18000W running
- QuietestPowerhorse s27000d97 dB
- Longest RuntimeGenerac #8917 GP18000EFI9h at 50% load
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Generac #8917 GP18000EFI
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Powerhorse s27000d
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