The Generac GP18000EFI (8917) is a powerful open frame generator with a rated wattage of 18,000 W and a starting wattage of 22,500 W. (Read full specs)
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Description
Zoom on the Generac GP18000EFI
In a nutshell, the Generac GP18000EFI is a powerful portable generator mostly geared towards:
- Professionals who want to ensure that a power failure will not prevent them from working
- Prudent homeowners who want a backup power source in case of a power outage
Over the following sections, you'll uncover its power characteristics, the selection of outlets it offers, its overall portability, and the supplementary features it includes.
Power & Run Time
Running on gasoline, the Generac GP18000EFI operates with a 816 cc Generac G-Force OHV 4-stroke engine, delivering 120/240V, with a running wattage of 18,000W and a peak wattage of 22,500W. The impressive running wattage makes this unit the 2nd biggest portable generator currently on the market, along with the Powerhorse 27000.
Its starting mechanism relies on a practical and straightforward electric starter (battery included).
The Electronic Fuel Injection (EFI) system enhances the engine's reliability, lowers fuel consumption, improves startup, reduces servicing, boosts stale fuel resistance, and offers better altitude adaptability.
Featuring a 14.2 gallons fuel tank, the GP18000EFI can provide power for around 9 hours at 50% load on a full tank (with fuel consumption averaging 1.58 gallons per hour).
As the GP18000EFI produces a clean sine wave, with a <5% Total Harmonic Distortion (THD), sensitive electronics may be plugged in the AC outlets safely.
Outlets
The control panel includes the following 7 AC outlets:
Despite not meeting the 'RV Ready' criteria, this Generac generator grants the advantage of simple RV compatibility via its L5-30R receptacle, enabling you to conveniently power your RV by using an L5-30P to TT-30R adaptor. Besides, as it features a twist-lock L14-30R receptacle, the GP18000EFI is transfer switch ready: in case of a power outage, you will be easily able to connect it to a breaker box and power your household.
Portability
Measuring L58.5 x W30.9 x H36.5 in, the Generac GP18000EFI showcases a classic open frame layout, guaranteeing stability and simple maintenance access to components, while facilitating air circulation. The design is ideal for rough environments and demanding outdoor use.
Although this generator is technically considered 'portable' (in the sense that it can be moved), its 442.8 lbs make it incredibly difficult to manually lift and transport. However, the constrained maneuverability is addressed with the assistance of its wheel kit (⌀12") and its folding handle, allowing for easy shifting once the generator is placed on the ground.
Features
The GP18000EFI's control panel
Embedded in the control panel of the GP18000EFI, a digital data center serves as a vital feature, offering comprehensive information on the lifetime run hours to aid in monitoring activity and status.
The generator includes a built-in fuel gauge, a quick, easy and convenient method of checking the device’s gas level.
From a security standpoint, the generator is furnished with an overload protection (circuit breaker) and an automatic low oil shut-off, ensuring peace of mind during operation.
The GP18000EFI also benefits from Generac’s COsense® carbon monoxide monitoring. This technology senses and manages CO output and shuts down the unit when necessary, to protect you from CO poisoning.
Besides the usual set of documentation and owner's manual (opens in a new tab) to get you promptly started, Generac also included some oil in the GP18000EFI's packaging.
The Generac GP18000EFI versus other generators
The following charts are provided to give you an idea of how some of the key specs of the Generac GP18000EFI compare to generators of similar power (between 14000 and 20000 W).
- With a dry weight of 442.8 lbs, the Generac GP18000EFI falls within the expected weight range for generators in the 14000 to 20000 rated wattage. If weight matters to you, one of the champions in this power range is the Genmax GM17000iE with only 308.6 pounds.
- Concerning its runtime, the GP18000EFI provides around 9 hours at a 50% load, indicating that it falls on the lower side compared to other generators of its power range. If extended autonomy is what matters most to you, the Westinghouse WGen20000 could be an excellent choice, offering one of the longest run times among units in its power category, reaching around 11 hours.
- Run time is crucial, but it heavily relies on the fuel tank's capacity. Thus, considering fuel efficiency alongside is essential. With a fuel usage of about 1.58 GPH at a 50% load, this generator falls within the typical gasoline consumption range observed in comparably powerful products. If you're placing a high priority on fuel consumption, the Genmax GM17000iE, with a low fuel consumption rate of 1.03 GPH, could be an option to consider.
Price comparison
As you can see from these interactive charts, when compared to other 14000-20000W generators, the Generac GP18000EFI is on the expensive side of the price range.
While certainly not the cheapest of its kind, purchasing it would most likely also mean enjoying the reliability of a high-end product.
The bottom line
- COsense® technology
- GFCI Outlets
- 4 different AC outlet types
- G-Force engine
- Electric start
- Clean sine wave
- Electronic Fuel Injection
- Decent weight (442.8 lbs)
- Decent fuel efficiency
- On the expensive side
- No recoil back-up
- No remote start
- Relatively low run time
Features and Specifications
| Inverter | No |
|---|---|
| Parallel capable | No |
| RV ready | No |
| Fuel | Gasoline |
| Engine | 816 cc Generac G-Force OHV 4-stroke |
| Starting system | Electric |
| Warranty | 3 years |
| Voltage | AC: 120/240V 60 Hz |
|---|---|
| Running watts | 18,000 W |
| Starting watts | 22,500 W |
| Running amps (@120/240V) | 150/75 amps |
| Peak amps (@120/240V) | 187.5/93.8 amps |
| Run time @50% load | 9 h |
| Run time @25% load | Unknown |
| GFCI outlets | Yes |
|---|---|
| Covered outlets | Yes |
| Automatic Voltage Regulation | Yes |
| AC outlets |
|
| DC outlets | No |
| Data center | Lifetime run hours |
| Indicators | No |
| Fuel tank | 14.2 gal |
| Fuel gauge | Yes |
| Weight | 442.8 lbs |
|---|---|
| Approx. dimensions (L x W x H) | 58.5 x 30.9 x 36.5 in |
| Noise (lower limit) | Unknown |
| THD | < 5% |
| Compliance | CARB, EPA |
| Security | Low oil and overload protection, CO monitoring |
| Spark arrestor | Yes |
| Neutral | Bonded to frame |
| Accessories included | Oil, battery, and wheel kit |
| UPC | 696471101324 |
Unlike many websites, we did our best to research each of the specs above. That being said, we are not immune to making the occasional mistake or omission. Should you notice any missing or incorrect values, don't hesitate to suggest improvements so we can address the issue.
About Generac
Generac Power Systems is an American based generator and power equipment manufacturer, founded in 1959. As its name suggests, the main focus of Generac are power generators, and other related electric equipment, such as switches, paralleling systems and small engines. The company has several manufacturing facilities based in the US, thus, their products are engineered and built in the USA. However, their components can be a mix of domestic and foreign parts.
Warranty Information
The Generac GP18000EFI is covered under a warranty for up to 3 years. This warranty may be limited and may not cover all parts of the generator.
For more information about the warranty of Generac generators, please consult Generac's warranty policies (opens in a new tab). Alternatively, you can also contact their Customer Support: 1-888-GENERAC (888-436-3722).
Questions & Answers
What can it power?
| Item | Running Watts | Starting Watts | |
|---|---|---|---|
| At home | Electric fry pan | 1500 | 1500 |
| Microwave (1000 watts) | 1500 | 1500 | |
| Dish washer | 1500 | 3000 | |
| AC (10,000 BTU) | 1500 | 2200 | |
| Sump pump (1/2 hp) | 1050 | 2150 | |
| Refrigerator (energy star) | 192 | 1192 | |
| Clothes dryer | 5400 | 6750 | |
| Electric grill | 1650 | 1650 | |
| Radio | 100 | 100 | |
| Total | 14392 W | 15892 W | |
| For work | Electric welder | 9000 | 9000 |
| Table saw | 1800 | 4500 | |
| Air compressor (1 hp) | 1600 | 6100 | |
| Grinder | 1400 | 2500 | |
| Drain cleaner | 250 | 250 | |
| Electric fence (25 miles) | 250 | 250 | |
| Bug zapper | 80 | 80 | |
| Total | 14380 W | 18880 W |
What is the noise rating of the GP18000EFI?
Due to the lack of standardization in noise emission measurement, Generac does not provide their units' noise levels.
Couldn't find the right answer for you? Ask your own question.
