Table of contents

Home Generators: Understanding Standby, Portable, Solar, and More for Reliable Power

EcoFlow

Table of contents

The U.S. utility grid is cracking under the strain of aging infrastructure and skyrocketing demand for electricity for electric vehicles, AI data centers, and the overall electrification of American life.

As extreme weather events like heat waves, hurricanes, and floods become more frequent and severe, so do power outages.

The Department of Energy warns that “blackouts could increase by 100 times in 2030 if the U.S. continues to shutter reliable power sources and fails to add additional firm capacity.” ^[1]

That’s one of the primary reasons why so many Americans are installing whole-home generators for reliable backup power during blackouts or portable generators for operating essential appliances when standby generators aren’t an option.

Fortunately, there are more options available to consumers than ever for whole-home backup power, including traditional standby generators, solar generators, and home backup battery systems.

Whole-home solar generators offer clean, quiet, low-maintenance backup power and long-term savings, while traditional standby generators provide lower upfront costs and unlimited runtime but require fuel, regular maintenance, and outdoor installation.

Which type of home generator is right for you?

Understanding Standby and Whole-Home Generators: What They Are and Why They Matter

Standby and whole-home generators typically integrate with your existing household wiring and electrical panel to enable automatic switch-over to battery or fossil fuel generator power during a blackout.

For example, EcoFlow DELTA Pro Ultra X can operate as a standalone home backup generator with <10ms switchover for a data-center-level uninterruptible power supply (UPS) or in 20 milliseconds or less when connected to your home circuitry through an automatic transfer switch.

Or you can take AI-powered home energy management to the next level by connecting to EcoFlow Smart Home Panel 3 or Smart Gateway (200A) to maximize electricity bill savings.

EcoFlow Smart Home Panel 3 uses AI-based load management to prioritize circuits and optimize grid/solar use.

Older standby generators may use a manual transfer switch, but most homeowners today prefer automatic switchover for added safety and convenience.

Unlike many other standby generators, like the Tesla Powerwall 3 and Generac PWRcell 2, the EcoFlow DELTA Pro Ultra X also functions as a standalone portable solar generator to which you can directly connect appliances and home systems like central heating and air conditioning (HVAC)..

Conventional portable gas and inverter generators don’t output nearly enough power to function as whole-house generators.

Key Features of Whole-Home Standby Generators

For most consumers, the critical properties to evaluate when purchasing a whole-home standby generator include:

Power Output Capacity

The maximum starting and running wattage of the generator must be sufficient to operate all your desired appliances, devices, and home systems like heating and air conditioning simultaneously.

Energy Storage and Expandability

Many new hybrid generators and home backup systems are modular, allowing additional battery capacity or inverter units to be added later. For example, the EcoFlow DELTA Pro Ultra X can expand up to 180 kWh of storage and 36 kW of output—enough to power even large homes or small businesses.

Fuel Source and Efficiency

Standby generators can operate on natural gas, propane, diesel, solar energy, or a combination of sources. Hybrid systems like the EcoFlow DELTA Pro Ultra X combine solar and grid charging for greater flexibility and cost savings.

Fuel efficiency and fuel availability during emergencies are critical—solar and battery systems can operate indefinitely with sufficient sunlight.

Fuel-powered generators like the Generac 7171 require either a continuous natural gas supply line or sufficient propane reserves to ensure uninterrupted runtime.

Power Quality (Clean vs. Dirty Power)

EcoFlow solar generators provide clean, stable, pure-sine wave electricity, ideal for sensitive electronics.

Engine-based generators output "dirty" power, which causes brief fluctuations in voltage and alternating current, technically known as total harmonic distortion (THD).

Inverter generators mitigate electrical fluctuations, but it's worth investigating just how "clean" the AC output is if you're powering precision electronics or a home office.

Automatic Start

Manual transfer switches and standalone whole-home generators like EcoFlow DELTA Pro 3 do exist, but most people prefer the added convenience of automatic switch-over to home battery backup or fossil fuel generator power.

While most standby generators like the Generac 7171 start automatically, they typically take 10–30 seconds to stabilize and transfer load — significantly longer than the sub-20 ms switchover of battery-based systems like EcoFlow DELTA Pro Ultra X.

Reliability

Power outages are frequently caused by extreme weather events like hurricanes, wildfires, blizzards, and floods. The last thing you need in a stressful situation is for your home backup power to fail.

No matter what type of generator you purchase, make sure it’s highly rated for reliability and durability, especially if it’s used infrequently.

Whole-home hybrid generators like EcoFlow DELTA Pro Ultra X have the added benefit of saving you money on energy bills with everyday use.

Traditional natural gas, diesel, or LPG standby generators are typically only used during blackouts.

The Generac 10 kW Wi‑Fi Enabled (Model 7171) is an example of a traditional air-cooled standby generator powered by natural gas or propane

If you don’t test traditional generators regularly, there’s a reasonable chance they might fail when you need home backup power the most.

Maintenance-Free?

Conventional standby generators that burn fossil fuels typically require routine maintenance.

Even older home solar panel systems that rely on flooded lead-acid solar batteries for energy storage need regular watering and other steps to remain reliable.

Many modern whole-home solar generators and standby inverter generators require little to no routine maintenance.

Except for rare circumstances, whole-home generators that use lithium iron phosphate (LFP/LiFePO4) battery chemistry require no maintenance except for the occasional firmware update.

Manufacturers of standby inverter generators that burn fossil fuels typically recommend biannual or yearly maintenance from a qualified professional to ensure everything is running smoothly.

For example, Generac recommends biannual inspections for its 10 kW Guardian Series standby generators, including oil and filter changes.

Portability and Indoor Use

Most standby and whole-home generators offer NO portability and for many homeowners, that’s not an issue.

For example, any standby generator that burns fossil fuels must be installed outdoors a minimum of 20 feet away from the house, typically on a fixed concrete pad for stability.

All standby and portable gas generators that burn fossil fuels produce deadly carbon monoxide, an odorless, invisible gas that can kill in minutes in an enclosed space, like a basement or garage.

The National Institutes of Health estimates that between 1,200 to 1,300 people per year die from carbon monoxide poisoning (all sources), with about half the deaths being unintentional.

Thankfully, EcoFlow’s portable power stations and whole-home generators are UL-certified for safe indoor operation.

And while EcoFlow DELTA Pro Ultra X isn't exactly light at +/- 183 lbs (85 kg), the built-in wheels make it far more portable than a standby inverter generator permanently installed at your home.

Warranty & Lifespan

EcoFlow whole-home generators include a 5-year warranty on inverters and batteries, with solar panels rated for up to 25–30 years.

Most fossil fuel generators include a 3–5-year limited warranty.

Permitting / Compliance

Solar + battery storage systems require basic electrical inspection.

Fuel-burning standby generators require full building, gas line, and emissions permits.

Understanding these key features helps homeowners choose the safest, most reliable, and cost-effective backup power solution—whether it’s a fuel-powered standby generator, a portable power station, or an advanced hybrid system like EcoFlow DELTA Pro Ultra X.

Whole-Home Solar Generators vs. Traditional Standby Generators

Property	Whole-Home Solar Generator*	Traditional Standby Generator (Natural Gas, Propane, or Diesel)
Energy Source	1. Sunlight (solar panels) charging a battery, no fuel needed. 2. Grid power (Charging only - no net metering) 3. Gas or Inverter Generator (optional backup charging with fossil fuel)	Burns fossil fuel (natural gas, propane, or diesel) to generate power.
Emissions	Zero emissions from solar charging. Runs on clean renewable energy (no combustion)	Produces exhaust and greenhouse gases through combustion.
Noise	Silent operation (no engine noise)	Loud engine noise when operating
Backup Power Capacity	Typically backs up essential circuits. Multiple battery units may be needed to power an entire home	Can support whole-home or partial-home power depending on size and installation
Runtime & Refueling	Limited by battery capacity. Once the battery is depleted, you must recharge using one of the available charging methods.	Can run indefinitely if fuel is available (continuous natural gas line or refilled tanks).
Installation	Can be installed indoors or outdoors, often near the main breaker panel. No exhaust, no clearance limits, and no special foundation required. Can also integrate into existing solar or grid systems via a smart home panel or gateway.	Must be installed outdoors only due to carbon monoxide emissions. Requires a level concrete pad, professional installation, fuel connection (natural gas line or propane tank), and local permit/inspection.
Safety	No fuel, carbon monoxide or gas risk (from solar or grid charging) Safe for indoor use.	Produces carbon monoxide and hot exhaust — must never be used indoors or near doors and windows.
Maintenance	Minimal maintenance (no oil changes or moving engine parts, periodic software or firmware updates only	Requires regular maintenance (oil and filter changes, tune-ups, and test runs)
Ease of Use	Automatic, silent switch to battery backup during an outage. No start-up delay when integrated with an automatic transfer switch or home energy management solution like EcoFlow Smart HomePanel 3. No refueling for solar panel or grid charging.	Automatic startup during outages. Detects power loss and turns on within seconds, not milliseconds. Some startup delay can potentially damage sensitive electronics like desktop computers and hard drives.
Upfront Cost	Higher upfront cost (often $25,000–$30,000 for a complete solar + battery storage system.)	Lower upfront cost ($7,000–$15,000 for generator plus installation).
Ongoing Costs	Very low ongoing costs. Sunlight is free. Minimal maintenance expenses.	Ongoing costs include fuel consumption and scheduled maintenance.
Return on Investment	Solar payback can be achieved in 3-5 years. Save up to $6000 a year on electricity bills. Learn more here. Solar batteries may eventually need a replacement after 10–15 years. Solar panels typically last 25-30 years	No financial return beyond backup security. Ongoing fuel and service costs.
Incentives	Eligible for federal, state, and local solar and clean energy tax credits or other government incentives.	Not eligible for renewable energy incentives or tax credits.
Everyday Use	Can be used year-round to store solar power and reduce or eliminate grid electricity use	Primarily for emergency use. Remains idle when grid power is available.
Smart Features	App monitoring and control, smart home integration, energy optimization, and remote firmware updates	Limited smart features. Basic auto start/stop and system alerts.
Warranty & Lifespan	Typical battery warranty 5 – 10 years; solar panels 25 – 30 years. Inverter systems often 10 years.	Warranty 3- 5 years on average. Engines may last 10-15 years with consistent maintenance.
Permitting / Code Compliance	Requires electrical inspection and grid interconnection approval** but fewer zoning restrictions.	Requires building, fuel line, and environmental permits. Must comply with setback and ventilation codes.
Environmental Impact	Runs entirely on renewable solar energy with zero emissions. Produces no noise or air pollution and helps reduce your home’s carbon footprint over time.	Burns fossil fuels and releases CO₂ and NOₓ emissions. Contributes to greenhouse gas output, residential carbon footprint, and local air pollution.
* Based on EcoFlow DELTA Pro Ultra X with one inverter and two home backup batteries ** Grid-tied systems only (bidirectional connection to the utility grid). Not required for EcoFlow DELTA Pro Ultra X

How Does EcoFlow DELTA Pro Ultra X Compare to Tesla Powerwall 3 and Generac PWRcell 2?

EcoFlow DELTA Pro Ultra X is a modular, semi-portable LFP whole-home generator system with flexible installation requirements that supports hybrid AC, solar, and fossil fuel generator charging and is scalable to 180 kWh of storage capacity and 36 kW of power output.

But how does it stack up against the competition from well-known brands like Tesla and Generac?

Here’s a direct comparison table so you can see for yourself.

EcoFlow DELTA Pro Ultra X | Tesla Powerwall 3 | Generac PWRcell 2 Comparison Table*

Category / Specification	EcoFlow DELTA Pro Ultra X	Tesla Powerwall 3	Generac PWRcell 2	Generac 10 kW Wi‑Fi‑Enabled Standby Generator (Model 7171)
Physical / General
Dimensions (inverter)	675×475×230 mm	1105×609×193 mm	22.8×8.1×24 in	48 × 25 × 29 in (1218 × 638 × 727 mm)
Dimensions (battery)	660×455×204 mm	Integrated (single unit)	23×10.75×70 in	N/A
Weight	≈85 kg (combined)	124 kg	113 lb (cabinet) + 62 lb (inverter)	338 lb (153 kg)
IP Rating	IP54	NEMA 3R / IP67	NEMA 3R	NEMA 3R (aluminum enclosure)
Operating Temperature	−20°C to 50°C	−20°C to 50°C	Charging: −5°C to 50°C; Discharging: −20°C to 50°C	−29 °C to 50 °C (with cold weather kit)
Noise Level	Low noise during operation (fan-cooled, no engine). No combustion or exhaust noise.	Quiet operation with active cooling fan	Battery Cabinet: Silent (no moving parts) Inverter: Low noise (<50 dB typical, not published)	61 dB(A) @ full load, 57 dB(A) @ exercise mode (at 23 ft / 7 m distance)
Mounting / Portability	Portable floor-mount	Wall-mounted (stationary)	Wall mount (with optional floor support)	Stationary pad-mounted outdoor installation
Battery System
Battery Chemistry	LFP (LiFePO₄)	Lithium-ion	NMC	N/A
Energy Capacity	6.14 kWh per module	13.5 kWh per unit	9–18 kWh per cabinet (3–6 × 3 kWh)	N/A
Expandable Capacity	Up to 60 kWh (per inverter) or 180 kWh (3 units)	Up to 81 kWh (4 Powerwall 3 units + 3 expansions each)	Up to 36 kWh (2 cabinets)	N/A
Battery Replacement	Replaceable modules	Non-replaceable	Replaceable modules	N/A
Warranty	5 years	10 years (4 if offline)	10 years or 7.56 MWh throughput	5 years (limited)
Inverter / Power Output
Continuous Output Power	12kW, 120/240V, 60Hz (Up to 36kW in 3 parallel units)	11.5 kW	11.5 kW (dual cabinet)	10,000 W (Propane) / 9,000 W (Natural Gas)
Surge Power	45 kW (Per Inverter). Peak current can reach 196A at startup, corresponding to a peak power of 240V × 196A = 45 kW	Not stated	Not stated	No surge output beyond 10 kW (LP) / 9 kW (NG) continuous rating
Output Voltage / Frequency	120/240 V 60 Hz	120/240 V 60 Hz	120/240 V 60 Hz	120/240 V AC, 60 Hz
Continuous Current	50 A	Not stated	48 A	~42 A (LP) / ~38 A (NG) at 240 V
Efficiency	Not stated	High (not specified)	98.5% CEC	N/A
UPS / Transfer Time	< 20 ms	Not stated	< 50 ms	~30 seconds (automatic detection and transfer)
Communication Interfaces	Wi-Fi, Bluetooth, App	Wi-Fi, Ethernet, LTE/Cellular	Wi-Fi, LTE, CAN	Wi‑Fi enabled; monitored via Generac Mobile Link app
Solar / Charging Capabilities
PV Input Voltage Range	80–500 V DC	N/A (AC-coupled only)	AC-coupled PV (~15 kW AC)	N/A
Max PV Power	30kW (10 kW per inverter, 2 × 5 kW inputs)	N/A (uses external solar inverter)	15 kW AC	N/A
Supported Charging Methods	Solar, AC, EV, generator	AC-coupled solar, grid	Solar, grid, generator	N/A (runs on NG/LPG fuel only)
Hybrid Charging	Yes (AC + solar or generator + solar)	No	Yes (AC-coupled hybrid)	N/A
Fossil Fuels
Fuel Type	Gas/Inverter Generator Compatible	N/A	Only with compatible Generac home standby generator	Natural gas (NG) or liquid propane (LP)
Fuel Consumption (NG / LP @ 50% / 100%)	N/A	N/A	N/A	NG: 101 ft³/h (50%) / 127 ft³/h (100%) / LP: 0.97 gal/h (50%) / 1.48 gal/h (100%)
Grid / Smart Features
Backup Type	Whole-home or partial backup via Smart Home Panel 3 or Smart Gateway (200 A). EcoFlow App + PowerInsight monitoring. Smart load management. AI and self-powered modes. Recharges from grid but does not support grid export or net metering	Whole-home / partial via Backup Gateway 2	Whole-home / partial via Smart Disconnect (200A)	Whole-home or partial backup (with ATS)
Monitoring & App	EcoFlow App, PowerInsight	Tesla App	PWRview App	Yes (Mobile Link remote monitoring)
Smart Load Management	Yes (AI/self-powered modes)	Yes (via Tesla app, not per-circuit)	Yes (Smart Disconnect + ecobee integration)	Yes (with optional Smart Management Modules)
Net Metering	No	Supported	Supported	No (backup-only, no grid export)
Generator Integration	Yes	No	Yes (up to 28 kW)	N/A

Ready to Discover EcoFlow's Scalable Home Generators and Secure Your Energy Independence Today?

U.S. homeowners and renters have never had more options to choose from for reliable home backup at a reasonable price.

EcoFlow DELTA Pro Ultra X offers many advantages compared to conventional standby generators and other home solar power + storage systems on the market today.

For a limited time, EcoFlow is offering massive discounts and installation support for EcoFlow DELTA Pro Ultra X.

Check out your available offers today!

Resources Cited

Energy.gov. “Department of Energy Releases Report on Evaluating U.S. Grid Reliability and Security,” July 7, 2025. https://www.energy.gov/articles/department-energy-releases-report-evaluating-us-grid-reliability-and-security.

Product References

EcoFlow DELTA Pro Ultra X

EcoFlow. DELTA Pro Ultra X User Manual. 2025. https://manuals.ecoflow.com/cn/product/delta-pro-ultra-x?lang=en_US
EcoFlow. DELTA Pro Ultra X Product Page. Accessed October 2025. https://www.ecoflow.com/us/products/delta-pro-ultra-x

Tesla Powerwall 3

Tesla Inc. Powerwall 3 Owner’s Manual & Safety Instructions. 2025. https://energylibrary.tesla.com/docs/Public/EnergyStorage/Powerwall/3/OwnerManual/en-us/Powerwall-3-Owner-Manual-EN.pdf
Tesla, Inc. “Powerwall.” Tesla. Accessed October 24, 2025. https://www.tesla.com/Powerwall.
Tesla, Inc. “Powerwall 3 Datasheet (en-US).” Tesla Energy Library. Accessed October 24, 2025. https://energylibrary.tesla.com/docs/Public/EnergyStorage/Powerwall/3/Datasheet/en-us/Powerwall-3-Datasheet.pdf.
Tesla, Inc. “Powerwall System Design and Installation Guide (North America).” Tesla Energy Library. Accessed October 24, 2025. https://energylibrary.tesla.com/docs/Public/EnergyStorage/Powerwall/3/Installation/en-us/Powerwall-3-Design-and-Installation-Guide.pdf.
Tesla, Inc. “How Powerwall Works.” Tesla Support. Accessed October 24, 2025. https://www.tesla.com/support/energy/Powerwall/learn/how-Powerwall-works.

Generac PWRcell 2

Generac Power Systems, Inc. PWRcell 2 Specification Sheet and Brochure. 2025. https://www.generac.com/globalassets/residential/dealers--installers/generac-installer-programs/solar--battery-installer-support/pc2brochure_specguide.pdf
Generac Power Systems. PWRcell 2 Battery Cabinet and Inverter Technical Specification Guide. Waukesha, WI: Generac, 2024. https://www.generac.com/globalassets/residential/clean-energy/pc2brochure_specguide.pdf
Generac Power Systems. PWRcell 2 Whole Home Power System Product Page. Accessed October 2025. https://www.generac.com/all-products/clean-energy/pwrcell-2
Generac Power Systems. PWRcell 2 Ecosystem Overview (Rev A). Waukesha, WI: Generac, 2024. https://www.generac.com/globalassets/residential/clean-energy/pwrcell/pwrcell2-overview.pdf
Generac Power Systems. Clean Energy Load Management Overview. Waukesha, WI: Generac, 2024. https://www.generac.com/globalassets/residential/clean-energy/pwrcell/clean-energy-load-management-overview.pdf

Generac 10 kW Guardian Series Home Standby Generator (Model 7171)

1. Generac Power Systems. 10 kW Guardian Series Home Standby Generator Model 7171 – Product Page. Accessed October 29, 2025. https://www.generac.com/residential-products/standby-generators/gaseous/standby-generator-10kw-wifi-enabled-7171

2. Generac Power Systems. Specification Sheet: 10 kW / 13 kW / 16 kW Guardian Series (Aluminum Enclosure, Air-Cooled Gaseous Generators). Rev. 2023. Accessed October 29, 2025. https://www.generac.com/SpecSheets/0168480SBY-A

3. Generac Power Systems. Guardian Series Home Standby Generators (10–26 kW Models) – Brochure. Accessed October 29, 2025. https://www.generac.com/GeneracCorporate/media/library/content/all-products/standby-generators/home-backup/guardian-series/guardian-brochure.pdf

4. Generac Power Systems. Owner’s Manual: 10–24 kW Air-Cooled Standby Generators (60 Hz). Rev. C, 2023. Accessed October 29, 2025. https://www.generac.com/GeneracCorporate/media/library/content/all-products/standby-generators/home-backup/manuals/0h0519-revc.pdf

5. Generac Power Systems. Features and Benefits – Guardian Series Home Standby Generators. Accessed October 29, 2025. https://www.generac.com/residential-products/standby-generators/guardian-series

*Disclosure: All specifications, performance data, and product descriptions in this comparison are drawn directly from manufacturer documentation and public datasheets as of October 2025. Information is provided for factual comparison only and may vary by region, firmware, or configuration.