EcoFlow vs. Generac Whole House Generators


This isn’t a fair fight.

For generations, fossil fuel powered home backup generators were the best option for protecting your home and family during blackouts and extended power outages.

But thanks to recent innovations and the growing adoption of residential solar power systems, Whole Home Generators aren’t just for backup anymore.

Running a household on fossil fuels when on-grid power is an option has never made sense. The ongoing fuel costs of gasoline, diesel, natural gas, and propane are simply too high.

And that doesn’t even take environmental costs into account.

Generous tax breaks and economies of scale have made switching to solar to reduce (or eliminate) your electricity bills and ensure energy security more affordable than ever.

How does a solar powered EcoFlow Whole Home Generator stack up against a traditional fossil fuel home backup system from Generac? 

Read on to find out.

What Is the Main Purpose of a Whole House Generator?

For decades, the primary function of a whole home generator was to provide emergency backup power in a blackout.

Most homeowners purchasing fossil fuel powered backup generators lived in remote locations where grid power was unreliable — or unavailable altogether.   

Until the recent advent of affordable solar generators and residential solar panel arrays, there was little reason to rely on a whole house generator unless on-grid power wasn’t an option.

But the game has changed.

US Solar Power Net Generation (2000 – 2022)

(Source: Statista)

Since 2011, US electricity production from solar has increased 73x — from under two terawatt hours to 145.6 terawatt hours in 2022. 

In 2022, electricity produced from renewables “surpassed coal (and nuclear)” for the first time.

Source: SEIA/Wood Mackenzie Power & Renewables U.S. Solar Market Insight Q3 2023

Residential solar installations in the US have followed a similar trajectory. Installed residential solar capacity has skyrocketed by 53x from 625 megawatts in 2010 to 32,750 megawatts in 2023.  

Thanks to rapidly improving photovoltaic and battery technology, more and more homeowners are opting for solar whole home generators not only for home backup but as an alternative to dependence on the utility grid.

Running your home with a fossil fuel generator like Generac’s Guardian 10kW Home Backup Generator is far more expensive than drawing electricity from the grid.

But with EcoFlow’s Whole Home Generator and solar panels, there are no ongoing fuel costs. Once your solar payback period is complete, all the money you save on electricity bills is yours to keep.

Instead of only looking to whole house generators for emergency backup, homeowners are increasingly switching to solar to meet some or all of their electricity needs. 

Thanks to off-grid innovators like EcoFlow, producing some or all of your home’s electricity with solar is a solid investment in your family’s future — and the planet’s.  

How Do Whole House Generators Work?

Whole home generators that harvest electricity from clean, renewable energy sources like solar work in an entirely different way from home backup generators that operate by burning fossil fuels. 

Solar is by far the most popular renewable energy option for residential use. Fossil fuel generators large enough to run a whole home typically burn natural gas or propane.

Let’s take a look at what makes each system tick below.

(Source: Creative Commons)

How Do Fossil Fuel-Powered Home Backup Generators Work?

Traditional generators work by burning fossil fuels to power an internal combustion engine. 

The mechanics of fossil fuel powered home backup generators vary based on the type of fuel they’re designed to use. But the basic principles remain the same.

Commonly used fuels for generators include:

  • Gasoline
  • Diesel
  • Natural gas
  • Propane (LPG)  

Small portable generators often burn gas or diesel. Large, permanently installed whole house backup generators frequently use LPG or natural gas. 

Generac’s Guardian 10kW Home Backup Generator is factory-fitted to run on natural gas, but it can be configured by a technician to operate using propane.

Using the 10kW Guardian as an example, let’s take a look at what goes on under the hood of a fossil fuel powered whole house generator.

  1. Fuel: A large tank or utility pipeline supplies natural gas or propane to the generator. 
  2. Combustion: An air intake mechanism draws the required oxygen into a combustion chamber where a spark or glow plug ignites the mixture. 
  3. Mechanical Power:  The mix of high-temperature/high-pressure gas expands, causing a turbine to spin quickly. The mechanical turbine, in turn, spins a generator rotor.  
  4. Electricity Generation: The spinning of the rotor produces a magnetic field. Electricity is generated through electromagnetic induction (EMI), also known as the generator effect.
  5.  Step-Up Voltage: The low voltage AC current produced by the generator effect is stepped up using a transformer.
  6. Electricity Distribution: The 120V AC output of the natural gas or LPG generator is fed into your home’s existing wiring through a transfer switch. Most modern home backup generators feature an automatic transfer switch, which will switch on immediately during a blackout. 

How Do Whole Home Solar Generators Work?

Unlike internal combustion powered generators — like Generac’s Guardian series — EcoFlow’s Whole Home Generators run on green, renewable solar energy captured by photovoltaic panels from the light of the sun.

Unlike fossil fuel generators, solar generators have no moving parts or ongoing fuel costs. Over time, you can save a significant amount of money on maintenance and electricity bills — and achieve energy independence — by switching to solar.

The specs and efficiency vary widely for solar panels and generators based on manufacturer and model, but residential solar generators all follow the same basic principles.

Let’s break it down.

  1. Solar Collection: The sun produces two kinds of energy — heat and light. Residential solar electricity systems capture photons from sunlight using the photovoltaic effect. PV modules like solar panels are typically monocrystalline or polycrystalline silicon solar cells. Up to several hundred cells are housed in each PV panel, protected by a durable covering — like tempered glass — and framed in steel. You should install solar panels where they will consistently receive direct sunlight — frequently on a roof.   
  2. Electricity Conversion and Storage: PV panels collect Direct Current (DC) electricity by harvesting energy from the sun. Numerous balance of system components are required to convert DC electricity to Alternating Current (AC) or household electricity. Residential solar power systems fall broadly into two categories: On-grid and off-grid. In off-grid systems, solar batteries are required to store electricity generated but not consumed during daylight hours. Solar power is intermittent — you can’t produce electricity at night and on cloudy days production will be reduced. The electricity stored in solar batteries will power your house when no electricity is produced. On-grid systems don’t require solar batteries as they automatically switch over to the utility grid when solar production is insufficient. However, many people choose to augment grid-tied systems with batteries to provide energy security during power outages.
  1. Integration With Existing Home Wiring: If you use a portable power station and solar panels, you can plug your appliances and devices directly into the unit. However, if you’re using a Whole Home Generator, you’ll likely want to connect it to your existing wiring using a EcoFlow Smart Home Panel or transfer switch. EcoFlow’s EcoFlow Smart Home Panel integrates with your home circuit board and provides an uninterruptible power supply (UPS) in the event of an outage. Instantaneous automatic switchover ensures that a blackout won’t damage sensitive electronics like computers and hard drives.    

Regardless of manufacturer, residential solar generators must contain the following components:

  • Photovoltaic modules (solar panels)
  • Inverter
  • Solar charge controller
  • Solar battery (optional for grid-tied systems)
  • Battery management system

Unlike many other whole house residential solar systems, the EcoFlow DELTA Pro at the heart of EcoFlow’s Whole Home Generator solutions provides all the required balance of system (BoS) components in one compact plug-and-play unit. Just connect EcoFlow’s portable, flexible, and/or rigid solar panels to your EcoFlow DELTA Pro, and you’re good to go.

EcoFlow DELTA Pro contains the following components:

Buying an integrated solar generator ensures you won’t have any compatibility or installation issues common when using separately manufactured components. 

Generac vs. Ecoflow: A Side-By-Side Comparison of Their Advantages

In many ways, comparing fossil fuel generators to solar generators is like comparing apples to oranges.

Fossil fuel generators are the traditional home backup option. Unfortunately, they produce toxic emissions that are dangerous for your family — and harmful to the planet. Natural gas and propane fueled generators are less dirty than gas and diesel options, but they still produce carbon monoxide, carbon dioxide, and particulate pollution.

 On the other hand, solar-powered Whole Home Generators produce no greenhouse gases or toxic emissions, making them the greenest choice — and, over time, the wisest investment.

Let’s take a look at the pros and cons of Generac’s 10kW natural gas/LPG generator vs. EcoFlow’s Whole Home Generator solutions.


Generac offers a wide range of fossil fuel powered generators and has recently begun to dip its toes into solar. 

The Guardian 10kW Home Backup Generator is Generac’s entry-level whole house backup solution powered by natural gas (standard) or liquid propane (optional). 

Generac sizes its home backup generators by AC output in kilowatts (kW). A generator’s AC output determines what kind of appliances you can operate simultaneously in your home. Ten kilowatts is the minimum AC output in the Guardian line — the maximum is 26kW. 

Available options include (LPG AC Output/Natural Gas AC Output in kilowatts): 10/9kW, 14/14kW, 18/17kW, 22/19.5kW, 24/21kW, 26/22.5kW. 

The more electricity a Generac fossil fuel generator produces, the higher the expense— both sticker price and ongoing fuel costs.  

Here is a summary of Generac Guardian’s pros and cons.


  • Low upfront investment
  • High AC output
  • Natural gas and propane burn cleaner than gas, diesel, and coal
  • Reliable backup power with natural gas grid access (or using LPG) 


  • Utility grid-dependent (if using natural gas)
  • Much more expensive than on-grid electricity —only suitable for home backup use
  • Ongoing fuel and maintenance costs
  • Fixed installation only
  • Must be factory set up for natural gas OR LPG (not both)
  • Not eligible for tax breaks or other government incentives
  • Noisy
  • Toxic emissions  (carbon monoxide)
  • No indoor use
  • Greenhouse gas emissions 
  • Increases your carbon footprint


EcoFlow’s Whole Home Generators provide reliable off-grid residential solar power solutions that you can expand to meet your needs.

The Starter Kit offers 3.6kW of AC output (7.2kW surge power) and 3.6kWh of electricity storage. With the addition of Smart Extra Batteries and an additional EcoFlow DELTA Pro, the advanced kit provides 7.2kW AC output and 21.6kWh of storage. Maximum storage is 25kWh.

Additionally, EcoFlow’s Whole Home Generators are seamlessly compatible with the Smart Generator Dual Fuel — giving you an LPG/gasoline-powered last line of defense in extended power outages.   


  • Off-grid energy independence
  • Clean, renewable energy source
  • Green and sustainable
  • No ongoing fuel or maintenance costs
  • Save on electricity bills — or eliminate them completely
  • Once your solar payback period is complete, the money you save on electricity bills goes straight into your pocket
  • Increases the value of your home
  • Industry-leading LiFePO4 (LFP) battery technology offers up to 10 years of daily use with no noticeable decrease in performance
  • Up to 6500W of charging input with multi charge allows you to recharge your whole home generator in under 2 hours. With solar only, EcoFlow DELTA Pro can recharge from 0-100%  in about four hours using 4 x 400W rigid solar panels.  
  • Solar panels last for decades
  • Best-in-class solar panel efficiency of 22-23% with EcoFlow’s rigid, flexible, and portable solar panels
  • Eligible for federal, state, and local solar tax credits and incentives  


  • Solar power is intermittent. To go fully off-grid with solar, you must have sufficient electricity production and storage capacity
  • Substantial upfront investment 
  • Numerous factors beyond your control can impact how much electricity your Whole Home Generator produces, including:
  • PV panels should be kept clean — free of dirt and debris

Generac Guardian 10kW Home Backup Generator vs. EcoFlow Whole Home Generator: The Specs

SpecificationsGenerac Guardian 10kWEcoFlow Whole Home Generator
AC Output (Minimum)9kW (Natural Gas)
10kW (Propane)
3.6kW Continuous output (7.2kW Surge)
AC Output (Maximum)9kW (Natural Gas)
10kW (Propane)
7.2kW Continuous output (14.4 Surge)
Storage Capacity (Minimum)N/A3.6kWh
Storage Capacity (Maximum)N/A25kWh
Solar Charge Capacity (Maximum)N/A3.2kW with 2 x EcoFlow DELTA Pro (16 x 400W PV Panels)
Weight338 lbs99 lbs
Dimensions48” x 25” x 29” inches25” x 11.2” x 16.4” inches 
Operating Noise61 decibels~50 decibels
Charging OptionsN/A5 (Solar/AC/Car Charger/EcoFlow Smart Home Panel/EV Charge Station)
Fuel Consumption @ Full Load (Natural Gas)127 cubic feet per hourN/A
Fuel Consumption @ Full Load (LPG)1.48 gallons per hourN/A
Battery ChemistryN/ALithium Iron Phosphate (LFP/LiFePO4)
Depth of DischargeN/A100%
Fossil Fuel Generator Cross-CompatibilityN/AYes (Smart Generator Dual Fuel)
Grid Tied/Off-Grid?Connects to natural gas utility lines (grid-tied) or runs on LPG (off-grid) Off-grid only
Indoor Operation?NoYes
Renewable Energy Source?NoYes
Uninterruptible Power Supply (UPS)YesYes
Plug and Play Installation?NoYes
Proprietary Solar Panels?N/AYes – Rigid, portable, and flexible monocrystalline PV panels (60W – 400W rated power)
Warranty (Per Solar Battery or Portable Power Station)5-year limited warranty 5 years (no cycle life restrictions)
App Monitoring and Control?Monitoring onlyYes
Federal Solar Tax Credit Eligibility?NoYes

Factors To Consider When Choosing A Whole House Generator

AC Output

Determining how much AC output you need is essential regardless of the type of generator or home backup system you choose. The generator’s maximum AC output determines what appliances you can switch on and operate simultaneously.  

The first step you should take before purchasing a whole house generator is to add up the total wattage of all the appliances you wish to run at the same time. The operating and surge power of the generator must exceed the starting and running wattage of the appliances you want to run.      


If you’re concerned about global warming, climate change, and the future of our planet, purchasing a solar powered whole house generator is hands down the best way to reduce your family’s carbon footprint.

Consumption of Primary Fossil Fuel Energy in the United States From 1990 to 2022 by Sector

(in trillion British Thermal Units)

(Source: Statista)

The only sector consuming more fossil fuels than electricity generation In 2022 was transportation. US electricity production required 21,577 trillion BTUs, and transportation required 25,910 trillion BTUs.

For the US to meet its net-zero carbon emission goals and remain a leader in the global battle against climate change, the transition to residential solar power must continue.

By choosing solar over fossil fuels for your electricity generation and home backup power needs, you’re making a meaningful contribution to the Earth’s future.  


Unless you have an unlimited budget, sticker price is always going to be a concern. 

But it’s essential to consider ongoing expenses as well as the cost upfront.

Nowhere is this more true than when considering a fossil fuel generator vs. solar. 

The upfront cost of a residential solar power system is significantly higher than a traditional fossil fuel generator.

For example, the Whole Home Generator Starter Kit is currently available for $2,799 direct from EcoFlow. Bundled with 2 x 400W rigid solar panels (required to generate electricity), the cost goes up to $4,299.

The current manufacturer’s suggested retail price (MSRP) for Generac’s Guardian 10kW Home Backup Generator is $3,879. 

The sticker price and initial cost per kilowatt hour (kWh) of a fossil fuel generator will always be lower than a solar powered system.

However, that doesn’t mean that Generac’s Guardian series is a better deal in the long run. 

When evaluating the financial cost of fossil fuel vs. solar, be sure to keep the following benefits of solar power in mind.

  • No ongoing fuel costs
  • No routine maintenance costs
  • Eligibility for tax breaks and other government incentives
  • Multiple financing options available
  • Increases the value of your home
  • Better for the planet

Weigh up the long-term benefits of solar vs fossil fuel for your family… 

You’ll probably find that solar is the better investment in the end.

Energy Independence

Generac’s Guardian helps protect you from power outages due to aging electrical infrastructure and extreme weather events. 

However, unless you opt for the LPG configuration, you’ll still be reliant on your utility company. Natural gas lines are less prone to interruptions from extreme weather and other adverse events. But should a gas outage occur at the same time as the electrical grid goes down, your family will be left without power.

LPG leaves you independent from the grid. But for a whole house generator, you’ll need a large propane tank — not 20 gallon canisters. Getting propane delivered during an emergency is easier said than done.

With a solar powered Whole Home Generator, you can produce electricity anywhere the sun shines. Add a Smart Home Generator as a last line of defense and you’ll truly have the best of both worlds when it comes to home backup.  


Unlike Generac’s Guardian series, EcoFlow’s EcoFlow DELTA Pro, Smart Extra Batteries, and Smart Generators are compact and easy to move. 

If you opt for a fixed installation with EcoFlow’s mountable solar panels, taking your power to go will be more tricky. However, you can always purchase portable solar panels with rated power wattage from 60W to 400W. Portable solar panels come with a kickstand and carrying case. 

You can use them on the ground to augment your home solar array — and easily take them to go if the need arises.   

Generac’s Guardian series starts at 338 lbs in weight and can weigh up to 518 lbs. Forget the fact that it needs to be connected to natural gas lines or a large LPG tank — it’s simply too heavy to go anywhere in a hurry.  

Frequently Asked Questions

What Size Generator Do I Need for a 2000 Square Foot House?

Your home’s square footage is a faulty metric for determining how much electricity output and storage you need. Calculate your generator requirements by adding up the starting and running wattage of all the appliances you want to operate simultaneously (kW). Ensure the AC output of the generator exceeds that total by at least 10%. If you’re going off-grid, estimate how long each appliance will run (kWh) between charges or refueling. 

Can EcoFlow Power a Whole House?

Yes, EcoFlow’s Whole Home Generators can power your entire house for extended periods. With up to 7.2 kilowatts (kW) of AC output (14.4kW surge) and 25 kilowatt hours (kWh) of battery storage, you can customize a whole home solar generator solution that’s right for your family’s needs. Lower or eliminate your electricity bills — and keep your family safe during blackouts — by switching to solar.

What Is the Best EcoFlow Home Generator?

There’s no one-size-fits-all answer to this question. The best EcoFlow home generator for you depends on your specific electricity consumption and storage needs. Calculate the starting and running wattage of all the appliances you wish to operate simultaneously. Ensure that the EcoFlow home generator you select exceeds that total by at least 10%.

Final Thoughts

If you want what’s best for your family (and the planet) in the long-term, the battle between solar powered generators and fossil fuels isn’t really a fair fight.

Traditional generators like Generac’s Guardian series have served a purpose. But like the fuels they run on, they’re becoming fossils from the past.

Switching to solar is the best long-term investment you can make in achieving energy independence and helping to combat human-made climate change.

Ready to embrace the future?

Check out EcoFlow’s Whole Home Generator solutions today.

EcoFlow is a portable power and renewable energy solutions company. Since its founding in 2017, EcoFlow has provided peace-of-mind power to customers in over 85 markets through its DELTA and RIVER product lines of portable power stations and eco-friendly accessories.

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