What Are the Downsides of Using a Natural Gas Generator?

Natural gas generators solve one of the biggest problems I see with backup power: storing enough fuel for a long outage. Connect the generator to an adequate gas supply, and you don’t have to keep filling cans or swapping propane cylinders.

That convenience comes with trade-offs. As of 2026, I wouldn’t choose a natural gas generator without looking closely at gas availability, output ratings, installation requirements, and the type of emergency I’m preparing for.

What Are the Biggest Downsides of a Natural Gas Generator?

A natural gas generator’s biggest weakness is that its fuel usually comes through infrastructure you don’t control. The generator may be sitting beside your house ready to run, but it still needs adequate gas pressure and an uninterrupted supply.

Definition: A natural gas generator is an engine-driven generator that burns utility-supplied or otherwise piped natural gas to create mechanical power, which the alternator converts into electricity.

The fuel itself has advantages. You avoid gasoline storage, natural gas doesn’t go stale in a tank, and a properly installed standby generator can start automatically during an outage.

• Good for: Automatic home backup, long utility outages, and homes with reliable natural gas service.
• Less ideal for: Locations without gas service, disaster plans requiring complete fuel independence, and applications needing maximum output from a portable multi-fuel generator.

Can a Natural Gas Generator Stop Working if Gas Service Goes Down?

Yes. If natural gas service is interrupted, a generator that depends entirely on that supply loses its fuel source.

The U.S. EPA’s power-resilience guidance specifically identifies interrupted natural gas service as a disadvantage of natural-gas generators. It also notes that earthquakes can damage gas piping and interrupt supply.

• Earthquakes: Broken gas mains or safety shutoffs can interrupt service.
• Infrastructure damage: Storms, construction accidents, fires, or other emergencies can affect distribution equipment.
• Utility shutdowns: A utility may shut sections of the system down when damage creates a safety concern.
• Pressure problems: A generator needs gas delivered within the pressure and flow range specified by its manufacturer.

The U.S. Department of Energy recommends planning for both electricity and natural-gas utility disruptions. That is why I don’t treat a gas-connected generator as completely independent power.

My rule is simple: treat the gas supply as part of the generator system. A powerful generator with an undersized, damaged, or unavailable fuel supply is still an unusable generator.

Do Natural Gas Generators Produce Less Power?

Many generators do produce less wattage on natural gas than they do on gasoline. This difference matters when you’re close to the generator’s maximum capacity.

A current tri-fuel model provides a useful real-world example. The Westinghouse WGen11500TFc is rated for 11,500 running watts on gasoline, 10,500 on propane, and 9,500 on natural gas.

Fuel	Peak Watts	Running Watts	Difference vs. Gasoline Running Output
Gasoline	14,500 W	11,500 W	Baseline
Propane	13,500 W	10,500 W	About 9% lower
Natural Gas	12,000 W	9,500 W	About 17% lower

This doesn’t mean natural gas is weak. It means you should size the generator using its natural-gas rating, not the largest number printed on the box.

Motor loads make this especially important. Air conditioners, well pumps, refrigerators, and sump pumps can require a brief surge of power when their motors start.

If you’re unsure where your home falls, my home generator sizing guide explains how to calculate running and starting watts before choosing a model.

Is Installing a Natural Gas Generator Expensive?

It can be. The generator purchase is only one part of the final installed cost, especially with a permanently installed standby system.

A natural gas generator may require several pieces of supporting work before it can safely supply the house.

• Gas-line sizing: The existing line must deliver enough fuel at the required pressure.
• Meter capacity: Some homes may need the utility to evaluate whether the existing meter can support the added load.
• Electrical transfer equipment: Standby systems normally use an automatic transfer switch or other approved transfer equipment.
• Site preparation: A permanent unit needs an appropriate outdoor location and mounting surface.
• Permits and inspections: Local electrical, fuel-gas, zoning, and building requirements may apply.
• Professional labor: Gas and electrical connections should follow manufacturer instructions and applicable codes.

I wouldn’t compare generators using purchase price alone. A cheaper unit can become the more expensive project if your existing gas service needs significant modification.

Are Natural Gas Generators Cleaner and Safer Than Gasoline Generators?

Natural gas can produce fewer local pollutants than some liquid fuels, but it is still a combustion fuel. A running engine still produces exhaust and must be treated as a carbon-monoxide source.

The EPA tracks emissions from natural-gas-fired reciprocating engines, including pollutants created during combustion. Natural gas should never be confused with zero-emission backup power.

• Carbon monoxide: Incomplete combustion can produce dangerous CO.
• Carbon dioxide: Burning natural gas releases CO2.
• Nitrogen oxides: High-temperature combustion can create NOx emissions.
• Methane: Leaks or incomplete combustion can release unburned natural gas.

Portable combustion generators need especially careful placement. The U.S. Consumer Product Safety Commission warns that generator exhaust can cause fatal carbon-monoxide poisoning and says portable units must be operated outdoors, away from openings.

Permanent standby generators have different manufacturer-specified installation clearances. Follow the exact installation manual and local requirements rather than applying portable-generator placement rules to a standby unit.

What about natural gas leaks?

Natural gas also introduces a separate fuel-leak hazard. Damaged hoses, loose fittings, faulty regulators, or improperly installed piping can allow combustible gas to escape.

I treat fuel connections as a safety system, not an accessory. My generator fuel safety guide covers the different handling concerns for gasoline, propane, diesel, and natural gas.

• Never modify a fuel connection beyond what the manufacturer permits.
• Have permanent gas piping installed and serviced according to local requirements.
• If you smell gas or suspect a damaged line, move to a safe location and contact the appropriate utility or emergency service.
• Keep working carbon-monoxide alarms in appropriate locations inside the home.

Are Natural Gas Generators Noisy or High-Maintenance?

Natural gas generators aren’t silent. A large engine, cooling fan, alternator, and exhaust system still create mechanical and exhaust noise.

Noise varies widely by generator design, enclosure, engine speed, load, and installation location. A permanently enclosed standby unit may sound different from an open-frame portable tri-fuel generator.

• Oil changes: Combustion engines need routine lubrication service.
• Spark plugs: Ignition components wear and may require periodic replacement.
• Air filters: Restricted airflow can hurt performance.
• Starting battery: Automatic standby systems depend on a healthy battery.
• Exercise cycles: Standby generators should run their scheduled self-tests.
• Fuel-system checks: Regulators, hoses, valves, and connections need inspection.

Automatic starting doesn’t mean maintenance-free operation. In my experience, the most frustrating standby-generator problems are often small issues that went unnoticed because the owner assumed an automatic system required no attention.

Is Natural Gas a Bad Choice for Major Disaster Backup?

Not necessarily, but it depends on the disaster you’re planning around. The key question is whether the event could damage both the electric grid and the natural-gas network.

The EPA notes that earthquakes can damage gas lines, while the Department of Energy recommends planning for utility disruptions rather than assuming every service remains available.

• Routine grid outage: Natural gas can be extremely convenient when gas service remains normal.
• Long storm outage: It avoids trips for gasoline and eliminates frequent refueling.
• Earthquake: Gas-line damage can remove the generator’s only fuel source.
• Remote property: Natural gas may not be available at all.
• Maximum resilience: Multiple fuel options reduce dependence on one supply chain.

For that reason, I like tri-fuel generators when portable backup makes sense. My tri-fuel generator guide explains when paying for gasoline, propane, and natural-gas capability is worthwhile.

When Is a Natural Gas Generator Still Worth It?

A natural gas generator can still be one of the best backup choices for a home with reliable gas service. Its strongest advantage is convenient runtime without storing large amounts of liquid fuel.

I would put natural gas high on the list when automatic operation and low fuel-handling effort matter more than complete independence.

Priority	Natural Gas Fit	Why
Automatic home backup	Excellent	No manual refueling when connected to reliable utility gas.
Long runtime	Excellent	Runtime isn’t limited by an onboard gasoline tank.
Maximum fuel independence	Poor to Moderate	A utility interruption can eliminate the fuel supply.
Maximum output from a multi-fuel portable	Moderate	Natural-gas wattage may be lower than gasoline wattage.
Minimal installation work	Poor to Moderate	Permanent systems can require gas and electrical upgrades.

The best choice isn’t the fuel with the shortest disadvantage list. It’s the fuel whose disadvantages you can realistically manage at your property.

Products I Recommend for a Safer, More Flexible Setup

If you’re planning to rely on natural gas, these are the kinds of products I’d consider for improving flexibility or detecting common fuel-related hazards.

Frequently Asked Questions

What is the biggest disadvantage of a natural gas generator?

The biggest disadvantage is dependence on the natural-gas supply network. If gas service is interrupted because of infrastructure damage, a utility shutdown, or another emergency, a natural-gas-only generator may be unable to run even though electrical power is still out.

Do natural gas generators use more fuel than gasoline generators?

Fuel use can’t be compared fairly by gallons because natural gas is normally measured in cubic feet or therms. More importantly, many multi-fuel generators deliver less rated electrical output on natural gas, so always compare the manufacturer’s fuel-specific wattage and consumption data.

Will a natural gas generator run during an earthquake?

It may, but an earthquake can damage gas-distribution infrastructure or lead to gas-service shutdowns. If earthquake resilience is a major priority, relying on natural gas alone creates a single fuel dependency that should be addressed in your emergency plan.

Are natural gas generators bad for the environment?

They generally have cleaner combustion characteristics than some gasoline or diesel applications, but they aren’t emission-free. Natural-gas engines can produce carbon dioxide, carbon monoxide, nitrogen oxides, and smaller amounts of unburned hydrocarbons or methane.

Is propane better than natural gas for a backup generator?

Propane gives you stored fuel on your property, which can provide more independence from utility gas service. Natural gas is usually more convenient for long runtime because you don’t need to refill cylinders, so the better option depends on the outage risks you’re preparing for.

Final Takeaway

The downsides of using a natural gas generator are real, but they don’t automatically make natural gas a poor choice. For many homes, reliable fuel delivery and automatic operation outweigh the lower output, installation work, emissions, and utility dependence.

I would focus on one question before buying: What happens if my primary fuel source fails? If the answer leaves your home without backup power, consider a dual-fuel or tri-fuel option and build redundancy into the plan.