When you’re shopping for a home generator to keep your lights on and appliances running during a power outage, one of the most important decisions you’ll face is choosing the right fuel type. Generators run on a variety of fuels—including gasoline, propane, diesel, and natural gas—and each option comes with its own pros, cons, and ideal use cases.
This comprehensive guide will help you understand the differences between generator fuel types so you can confidently choose the best emergency backup power solution for your home.
Why Fuel Type Matters When Choosing a Generator
The type of fuel your generator uses will impact more than just its performance. It affects:
- Availability during emergencies
- Runtime and fuel storage
- Generator size and power output
- Maintenance needs and operating costs
- Environmental impact and emissions
Let’s break down each common fuel type to understand the benefits and trade-offs.
1. Gasoline-Powered Generators
Gasoline generators are among the most common and widely available backup power solutions for homes. Most portable and inverter generators run on unleaded gasoline, making them easy to fuel up in a pinch.
✅ Pros of Gasoline Generators
- Widely Available: Easy to purchase at gas stations or stores
- Lower Upfront Cost: Generally more affordable than other types
- Portable: Ideal for small to mid-sized portable generators
❌ Cons of Gasoline Generators
- Short Shelf Life: Gasoline degrades in 3–6 months without stabilizers
- Refueling During Storms: Gas stations may be closed or out of fuel
- Higher Emissions: Less environmentally friendly than propane or natural gas
- Shorter Runtime: Smaller tanks require more frequent refueling
🏠 Best For:
Homeowners needing a budget-friendly, short-term power source for refrigerators, lights, and basic electronics during brief outages.
🛠️ Top Pick:
Westinghouse WGen7500 Gasoline Generator – Affordable, electric start, and powerful enough for essential home loads.
2. Propane (LP) Generators
Propane-powered generators offer a cleaner-burning, longer-lasting fuel option. Propane can be used in both portable generators and permanent standby systems, and it’s especially popular for dual-fuel units that run on both propane and gasoline.
✅ Pros of Propane Generators
- Long Shelf Life: Propane can be stored indefinitely without degradation
- Cleaner Emissions: Burns cleaner than gasoline or diesel
- Less Engine Wear: Burns cooler, reducing generator maintenance
❌ Cons of Propane Generators
- Lower Power Output: Slightly less efficient than gasoline or diesel
- Needs Large Tanks: High fuel consumption requires big storage tanks
- Pressurized Storage: Requires careful handling and installation
🏠 Best For:
Homeowners who want a clean, long-lasting fuel source and already use propane for home heating or cooking.
🛠️ Top Pick:
Champion 7500-Watt Dual Fuel Generator – Switches between gasoline and propane easily, with electric start and great runtime.
3. Diesel Generators
Diesel-powered generators are known for their efficiency, power output, and durability. They’re less common for residential use but are favored in larger off-grid, commercial, and rural setups where long-term, reliable power is critical.
✅ Pros of Diesel Generators
- Excellent Fuel Efficiency: Longer runtime per gallon
- Durable Engines: Built to run longer and require less maintenance
- High Power Output: Ideal for heavy loads and continuous operation
❌ Cons of Diesel Generators
- Expensive Upfront: Higher initial purchase price
- Noisy: Generally louder than other fuel types
- Fuel Storage Limits: Diesel degrades over time and needs additives
🏠 Best For:
Homeowners in rural areas or those who need powerful, long-lasting generators for extended outages or off-grid living.
🛠️ Top Pick:
Generac XD5000E Diesel Generator – Commercial-grade diesel performance for serious backup power.
4. Natural Gas Generators
Natural gas generators are a popular choice for whole-house standby systems. If your home is connected to a natural gas line, this fuel source provides unlimited runtime, convenience, and automatic operation during an outage.
✅ Pros of Natural Gas Generators
- Unlimited Runtime: Taps directly into your utility gas line
- Cleanest Burning Option: Lower emissions than all other fuels
- Convenient and Automatic: No need to store or refill fuel
❌ Cons of Natural Gas Generators
- Not Available Everywhere: Requires access to natural gas infrastructure
- Professional Installation Required: Must be permanently installed with permits
- Higher Upfront Cost: Whole-home systems are a significant investment
🏠 Best For:
Homeowners who want a permanent, worry-free backup solution with automatic activation and access to municipal gas lines.
🛠️ Top Pick:
Generac Guardian 22kW Standby Generator – Whole-home power with natural gas or propane connection and automatic operation.
Fuel Type Comparison Chart
| Fuel Type | Availability | Shelf Life | Emissions | Maintenance | Power Output | Best For |
|---|---|---|---|---|---|---|
| Gasoline | High | 3–6 months | Moderate | Moderate | Good | Short outages, portable needs |
| Propane | Moderate | Indefinite | Low | Low | Moderate | Clean backup, dual fuel systems |
| Diesel | Moderate | 12–24 months (w/ additives) | High | Low | Excellent | Heavy loads, long runtime |
| Natural Gas | Utility-dependent | Unlimited | Very Low | Low | Excellent | Whole-home, long-term coverage |
Which Generator Fuel Type Is Right for Your Home?
✔ Choose Gasoline if:
- You want a low-cost, portable generator for short-term emergencies
- You have easy access to fuel during outages
✔ Choose Propane if:
- You want long shelf life, cleaner emissions, and reliable fuel storage
- You already use propane at home for heating or cooking
✔ Choose Diesel if:
- You need high power output and long runtime efficiency
- You live off-grid or have extensive backup needs
✔ Choose Natural Gas if:
- You want a seamless, automatic standby generator solution
- Your home is connected to a natural gas line
Final Thoughts: Generator Fuel Types Matter
Choosing the right generator fuel type is about more than just what’s available—it’s about reliability, safety, and how well your system will serve you during an emergency. Whether you opt for a portable gasoline unit, a propane-powered dual-fuel generator, a powerful diesel model, or a whole-home natural gas system, make sure it aligns with your energy needs, location, and usage habits.
A little planning today can ensure you’re never left in the dark tomorrow.
Want Help Choosing a Generator?
Be sure to read our full buyer’s guide: What Size Generator Do I Need for My Home? for more tips, sizing tools, and top generator recommendations.