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The Generac ecogen series 5818- 6kw standby generator for off grid applications (lp) is available for purchase today.

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Generac EcoGen Series 5818- 6kW Standby Generator for Off Grid Applications (LP)

(Based on expert analysis, manufacturer ratings and customer reviews)
4.2 out of 54.2 out of 54.2 out of 54.2 out of 54.2 out of 5
6 Reviews
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Ships Tuesday, Oct 25th

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  • Features
  • Specs
  • 8
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Airooled Standby Generators
6 kW
Rated Watts
120 Single-Phase
The First Generator Intended For Alternative Energy Interaction
Designed to interact w/ off-grid renewable energy applications
Capable of tying into an inverter & battery storage system

Generac OHVI Air-Cooled Engine
Maximizes engine "breathing" for increased fuel efficiency
Plateau honed cylinder walls & plasma-moly rings run cooler

Exclusive Premium Oil Recovery & Circulation System
Provides extended run capability, 500 hours between oil changes

Nexus™ Digital Controller Monitors & Controls All Functions
Provides system status - compatible with Nexus™ wireless monitors

Ultra Quiet, Low RPMs - Only 52 dB(A) Under Normal Load
Vertically mounted, belt-driven engine drives at 2600 RPMs
Longer life & drastically quieter operation than other systems

Weather Protective Steel Enclosure w/ RhinoCoat™ Finish System

Two-Wire Start - Easily Connect To The Inverter Control Wires
Automatically start/stop the generator for battery charging

Factory Wired 120V - Capable of 240V (Conv. Kit Sold Separately)
Accommodate 240V inverter systems or two systems paired

3 Year/2000 Hour Limited Warranty (VOID if installed in CA)
Engine Brand
Generac OHVI
530 CC
Consumer Engine Warranty
3 Years
Engine RPM
2600 RPM
Low Oil Alert/Shutdown
Product Specs
120 Single-Phase
60 Hertz
Surge Watts
6000 Watts
Rated Watts
6000 Watts
Fuel Type
LP Power Capacity
6000 Watts
LP Fuel Consumption @ 50% Load
0.82 (BTU: 74,415 BTU/HR) gallons/hr
LP Fuel Consumption @ 100% Load
1.47 (BTU: 133,403 BTU/HR) gallons/hr
Rated Amps
50 @ 120 Volts (Single Phase) Amps
Decibel Rating @ 7m
52 dbA
Transfer Switch
Not Applicable
Not Included (525 CCA)
Mounting Pad
Composite (Included)
Cooling System
Air Cooled
UL Listed
Made in USA
387 Pounds
Product Length
48 Inches
Product Width
25 Inches
Product Height
29 Inches
Consumer Warranty
3 Years

*Ask Mike about the Generac 5818. Sorry, no repair questions:




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  8 Questions
Q: Hi Jim - question - what is it that is special about the EcoGen generator for off-grid power versus say the Generac Guardian 8kW Standby. The system is about $1500 more expensive - I recognize that a previous answer you provided online said that having solar makes things more complicated, but there must be something unique about this generator that you need to use it for this application? Can I use the 8kW generator to manually turn on and off back-up power or charge my solar system?
by Jeff Brown from New York on April 03, 2014

A: The overall engine design and oil lubrication system is much more robust in the EcoGen (5818) system allowing the long term running when paired with a solar systems inverter which will also start the generator will 2-wire control.

The regular 8kW (6237 & 6245) emergency backup standby generators are designed to work with standard applications where utility service is present as the generators internal controller must be connected to utility power to properly operate.

The generator must also be connected to the appropriate automatic transfer switch for proper communication. The connections and controls are not the basic 2-wire start as there are 6 control wires that must be connected to the automatic transfer switch for proper utility service monitoring and generator controls.

The Generac Guardian Home Standby units are not designed, engineered or warranted for use in a solar system.

by Mike, Product Expert
Q: I have a 9165 watt solar system which reverse meters to the grid. If the power is off, I have no power. Will one of the natural gas backup generators work with my system, or does the solar add complications?

by Erik Johnson from Colorado on December 16, 2013

A: Having multiple power sources can make things very complicated. However, we do offer two models of generators which can be turned on and off by your solar systems inverter system.

Generac's EcoGen model 5818 is specifically designed for use with alternative power options such as solar and wind and comes with a 3 year warranty......

Generac EcoGen Model 5818

Kohler offers their 14kW home standby generator capable for use with solar systems but they only offer an 18 month warranty as they are not specifically designed for this type of application. The generators internal controller can be adjusted to accept a 2 wire start from your inverter system.

Kohler 14kW Model 14RESA

We do recommend consulting with a local installer as your application can have some special parameters and installation requirements. They will also be familiar with your local code requirements so installation is done properly.

by Mike, Product Expert
Q: I purchased a Generac 5818 LP generator from you a couple months ago.
Unfortunately the instruction manual is well hidden or went missing before I got it. How do I go about receiving the installation and operation manual?

by Carl Wright Wright from Arizona on October 18, 2013

A: The best way to get access to new manuals is through the Generac website using the serial number from the generator.

Here is the link to access the manuals.....

Generac Manual Search

by Mike, Product Expert
Q: just bought the eco generator today and need a cold start/warm kit for battery etc.. but seeing an exact fit for what I have ??? is there one???
by Chris from Connecticut on October 21, 2011

A: Unfortunately, there is not a cold weather kit for the Eco-Gen at this time.
by Mike, Product Expert
Q: What is a composite pad ?
by CHARLES BLYTHE from North Carolina on April 08, 2011

A: The composite pad is a strong, lightweight mounting pad provided to simplify the installation. By including the pad with the generator, installation time and cost is reduced since a concrete base is no longer a requirement.
by Mike, Product Expert
Q: Is this wireless monitor compatible with the Generac CorePower series ?
by Tim from New York on March 01, 2011

A: The Generac Nexus™ Advanced Wireless Monitor is only compatible with the Guardian and EcoGen Series models with the internal Nexus™ Controller and cannot be connected to the CorePower model.
by Mike, Product Expert
Q: Hello Jim, do you have, or can you recommend stand-by generator installers for the Houston, Texas area? We are in the N.W. Houston area.
by David Reece from Texas on February 13, 2011

A: Since we do not get involved in the installation process and since we ship all over the continental US we do not have a list of installers to provide. You can contact a local Generac dealer who may do installations at a reasonable price and will provide you with the best installation knowledge. You do not necessarily have to purchase a Generac generator from them to utilize their installation and they would be your resource for maintenance and warranty repairs.

Service Dealers

by Mike, Product Expert
Q: Is this generator (Model 5884) a good choice for off grid solar system backup. 14kw not essential circuit?
by Avery Edwards from Colorado on January 25, 2011

A: The Generac 5884 generator is specifically designed for emergency backup only and will not be warranted in an off-the-grid application.

Generac did come out with a new model specifically designed for off-the-grid and solar applications.

Off Grid Generator

by Mike, Product Expert
Generac 5818 Reviews & Ratings
Overall Rating
4.2 out of 54.2 out of 54.2 out of 54.2 out of 54.2 out of 5
Quiet (2)
High Quality (1)
Reliable (1)
Durable (1)
Features (1)
Expensive (1)
Low Quality (1)
60% of respondents would recommend this product to a friend
6 Reviews  Sort by 
Most Helpful Critical Review
3 out of 53 out of 53 out of 53 out of 53 out of 5
No Way...
Got this generator from a local company. The first one lasted around 800 hours before it started smoking from the exhaust...badly. After 4 months finally got another one. 978 hours on this one and the same problem...smoke out of the exhaust. I have a cabin. This has to power lights, microwave, well, refrigerator. This one has to go, and get a Honda.
Al Does Not Recommend This Product
Manufacturer Response
Brand Rep
We are disappointed to learn of your unit's issues. If your generator ever experiences operational complications, we would recommend contacting an independent authorized service provider in your local area for any diagnostic or servicing work that may be required. Please know that these trained professionals are able to not only identify the cause of your unit's issues, but can also provide any applicable warranty coverage to your generator as well. To locate an independent authorized service provider closest to you, please use your postal code for searching purposes here: . Moreover, if you would like to speak with us directly regarding your personal experience, please contact us at 888-GENERAC (436-3722); we are available 24/7.
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Purchased from Electric Generators Direct
Purchased 4/2/13
Total Helpful Votes
30 Helpful Votes
5 out of 55 out of 55 out of 55 out of 55 out of 5
Oh So Quiet
I was a little nervous with the spec for how quiet the generator was supposed to be, as i was planning on installing it into a renewable energy system at a cabin in the woods. Last thing i wanted to do was to drown out the silence of the woods with a noisy generator. I couldn't believe how quiet it was. I have a little portable 1000W suitcase unit and this is even quieter than that! I can't wait to get the cabin done and install this for real and see how well it does out there. VERY... more
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Brian E.
Austin, TX
Purchased from Electric Generators Direct
Purchased 5/29/13
Total Helpful Votes
27 Helpful Votes
3 out of 53 out of 53 out of 53 out of 53 out of 5
Generac: Slow And Unreliable
Unit I received from Electric Generators Direct seized in the first 5 minutes of operation. Took me 3 months to get replacement and scavenger pump did not work for the additional reservoir. This caused the engine to overfill with oil and smoke badly. Still waiting on a resolution with that. It runs good but only with the engine sump and not the extra large reservoir filled with oil.
Pros: Features, Quiet
Cons: Low Quality, Expensive
Brian Does Not Recommend This Product
Was this review helpful?
Purchased from Electric Generators Direct
Purchased 8/27/14
Total Helpful Votes
12 Helpful Votes
4 out of 54 out of 54 out of 54 out of 54 out of 5
Offgrid Backup Generator
I have my generator, the Generac EcoGen 5818, 6kW all connected and it works fine. However I must say the quality control of Generac is very bad. I have 2 neighbors with the same generator with the same experience. There were several loose bolts. Luckily because of my neighbor's experience, I knew to check.

Also when I first tried to start it, one of the oil lines was disconnected and oil went everywhere, and a spark plug wire was also disconnected. Generac needs to train their people... more
Lou Recommends This Generac Product
Mike, the Generator Expert
Product Expert
If you have input on Generac's quality control, you will need to contact Generac directly to let them know. We haven't received many complaints about Generac quality control issues, and they would much rather hear directly from you (the customer) than to be forwarded this information from us.
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Robert B.
Groveland, NY
Purchased from Electric Generators Direct
Purchased 2/18/14
Total Helpful Votes
10 Helpful Votes
5 out of 55 out of 55 out of 55 out of 55 out of 5
Eco-gen #2
Off grid living is sometimes more expensive than I'd like to admit. I have just purchased my 2nd Eco-gen after #1's inverter seized. I'm not complaining, as it had nearly 5,000 hours on it and the motor section is still fine. It's a trickle down sorta thing. My battery bank had problems which resulted in extra gen use. That has been taken care of and now I will replace the inverter portion of #1 and keep it as backup to my backup. Exellent product here that never skipped a beat with basic... more
Pros: Quiet, Durable, Reliable, High Quality
Robert Recommends This Generac Product
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John G.
Newman Lake, WA
Purchased from Electric Generators Direct
Purchased 12/22/14
5 out of 55 out of 55 out of 55 out of 55 out of 5
Great Generator...a Few Loose Ends
After much research we installed this generator to replace a 10kw Kohler. Primary decision based on this generator being specifically made for off-grid application and we have been living off-grid for ten years. Generator arrived on time and in good condition. Two problems were soon evident. The first was the generator would try to start, rev up to 4200 rpms and shut down for "overspeed."

Owners Manual very sparse on details and really no help for trouble shooting. Called Generac... more
John Recommends This Generac Product
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  • Ships via Semi-Truck
  • Requires a loading dock or forklift
  • Free to Lower 48 States
We currently CANNOT ship this product to Alaska, California, Hawaii, Massachusetts or any destination outside of the United States
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  • Safely Lowers Products Off the Truck
  • Requires Special Hydraulic Lift
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