If you’ve ever experienced a long power outage, you know how disruptive it can be. From losing heat or air conditioning to spoiled food and disconnected devices, the effects are more than just inconvenient—they can be expensive or even dangerous. That’s why more homeowners are turning to whole-house generators. But one common question remains: Can a whole-house generator run everything in my house, including HVAC and appliances?
The short answer is yes—if your generator is properly sized and installed, it can power your entire home, including central air systems, refrigerators, lights, well pumps, electric stoves, and more. The key is choosing the right capacity and configuration to match your household’s total electrical load.
In this article, we’ll break down how whole-house generators work, how much power your appliances really use, and what you need to consider to ensure your generator can truly run your entire home during a power outage.
What Is a Whole-House Generator?
A whole-house generator, also known as a standby generator, is a permanently installed backup power system connected to your home’s electrical panel. Unlike portable generators, whole-house models are:
- Hardwired into your home’s main power system
- Fueled by natural gas or liquid propane
- Equipped with an automatic transfer switch that turns the system on automatically within seconds of a power outage
- Capable of powering all circuits in your home—if properly sized
Whole-house generators are ideal for homeowners who want reliable, uninterrupted power for all major systems and appliances, including heating, air conditioning, and electric cooking appliances.
How Much Power Do You Need to Run Everything?
To determine whether a whole-house generator can run everything in your home, you first need to understand your home’s total electrical load. Every appliance and system in your house draws a certain number of watts (or kilowatts) of power.
Common Appliance and HVAC Power Usage:
| Appliance/System | Average Running Watts |
|---|---|
| Central Air Conditioner (3-ton) | 6,000W |
| Electric Furnace | 10,000W |
| Refrigerator | 600W |
| Freezer | 500W |
| Electric Range | 5,000W |
| Microwave | 1,000W |
| Washer & Dryer | 4,000W |
| Dishwasher | 1,200W |
| Lighting & Outlets | 1,000W – 2,000W |
| Wi-Fi, TV, Computers | 200W – 500W |
🧠 Total Estimated Load: For a fully equipped home, you’re looking at 20,000 to 26,000 watts (20–26kW) of continuous power—plus a margin for surge capacity during startup of motors and compressors.
What Size Generator Do You Need to Run Everything?
If you want to power your entire home, including HVAC and large appliances, you’ll need a standby generator that delivers at least:
- 20kW–22kW: Sufficient for most homes up to 3,000 sq ft
- 24kW–26kW: Ideal for larger homes or homes with electric heating
- 30kW–38kW: Recommended for large custom homes, homes with pools, EV chargers, or workshops
🔥 Important: Your generator must be sized not just for total running watts, but also starting wattage (surge load) when large motors cycle on.
Can a Generator Run HVAC and High-Draw Appliances Simultaneously?
Yes, but only if the generator is properly sized. Central air conditioners, electric furnaces, water heaters, and dryers are considered “high-draw” appliances that place a heavy load on your system.
If you plan to use multiple high-draw systems at once (e.g., central AC, water heater, and dryer), your generator must be rated for the combined load—or use a load management system to prioritize circuits.
Load Shedding for Smarter Operation
Some whole-house generator systems include smart load management panels that can temporarily turn off non-essential appliances when the load nears capacity—ensuring your HVAC or refrigerator stays on.
This lets you use a slightly smaller generator without sacrificing coverage. For example, a 20kW generator might not run your entire home at once, but with load management, it can rotate systems as needed.
What Fuel Types Are Used for Whole-House Generators?
Whole-home standby generators typically run on:
- Natural Gas: Continuous fuel from city lines; no refueling required
- Propane (LP): Stored in on-site tanks; longer shelf life, great for rural areas
The fuel type does not affect the power output, but it does influence runtime, installation, and fuel availability during emergencies.
Estimated Fuel Usage (Propane):
- 20kW generator: ~2.5–3.0 gallons/hour at full load
- 24kW generator: ~3.0–3.5 gallons/hour at full load
- 30kW+ generator: ~4.0–5.0 gallons/hour
💡 Tip: For uninterrupted operation during extended outages, connect to a 250–500 gallon propane tank or natural gas line.
Best Whole-House Generators for Full Home Coverage
🛡️ Generac Guardian 24kW
- Ideal for whole-home backup with HVAC and high-draw systems
- Smart transfer switch and mobile monitoring
- Runs on natural gas or propane
⚡ Kohler 26kW RESV
- Premium performance and corrosion-resistant design
- Fast 10-second startup with commercial-grade engine
- Handles whole-home loads with ease
🔋 Champion 14kW Home Standby
- Best for essential loads or medium-sized homes
- Affordable and efficient operation
- Includes automatic transfer switch
Installation Requirements for Running the Entire Home
Installing a generator capable of powering your whole home requires:
- Load calculation: Performed by a licensed electrician
- Transfer switch: Connects generator to main panel
- Fuel connection: Natural gas line or propane tank hookup
- Permit and inspection: For safety and code compliance
🧰 Pro Tip: Ask your installer about integrating smart home monitoring and automatic exercise cycles for peace of mind.
FAQs About Running Your Whole House on a Generator
Q: Can my generator run central air and an electric stove at the same time?
Yes, if it’s sized appropriately. A 24kW+ unit can typically handle simultaneous operation of multiple high-wattage appliances.
Q: Will I notice a delay when the generator kicks on?
You may notice a 10–30 second delay during switchover, but then all systems will operate normally.
Q: Do I need to manually turn on appliances?
No. Once power is restored through the generator, your circuits and appliances will resume automatically, just as they do with utility power.
Q: Will I have to ration usage during an outage?
If your generator is properly sized or load-managed, you won’t need to ration. However, with a smaller generator, you may need to cycle high-demand appliances.
Q: Can I install the generator myself?
No. Whole-house generator installation must be performed by licensed professionals to ensure code compliance and safe operation.
Conclusion: Yes—With the Right Setup, You Can Power It All
If you invest in the right size generator, you can run your entire home—including HVAC, refrigerators, washers, stoves, lights, and electronics. Today’s standby generators are more powerful, efficient, and reliable than ever, making them a smart choice for homeowners who value comfort and continuity during outages.
With automatic operation, fuel flexibility, and full-home coverage, a standby generator offers true energy independence—whether you’re facing hurricanes, winter storms, or grid failures.
Still Shopping for the Right Generator?
Start here: What Size Standby Generator Do I Need for My Entire Home? — our complete guide to choosing the perfect system for whole-home coverage, including sizing tools, fuel comparisons, and cost breakdowns.