Storing generator fuel safely
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How to store gasoline and propane for a generator, how much to keep, how to keep it fresh, and refueling safety.
A generator is only as useful as its fuel. During regional outages gas stations may be closed, so many households store fuel ahead of time. That fuel must be stored safely and kept fresh.
Gasoline storage basics
- Use only containers made and labeled for gasoline. Keep caps tight.
- Store fuel outside the living area, in a detached shed or a well-ventilated garage away from water heaters, furnaces, and other ignition sources. Follow local fire codes, which often limit the amount you can keep.
- Keep containers out of direct sun and away from children.
- Never store gasoline in the house or basement.
NFPA advises storing generator fuel in approved containers and away from fuel-burning appliances.
Keeping gasoline fresh
Gasoline breaks down over time. It can leave gum and varnish in a carburetor, which is a common reason a generator that sat all year will not start. Two habits help:
- Add fuel stabilizer when you fill the storage can, following the product label.
- Rotate the fuel. Pour stored gas into your car and refill the can with fresh gas on a regular schedule.
Many generator manuals also recommend running the carburetor dry or draining it for long storage. Check your manual; procedures differ.
Propane and dual-fuel generators
Dual-fuel generators can run on propane, which does not go stale. Standard barbecue-size cylinders are easy to swap, and larger cylinders or a permanently installed tank extend run time. Propane contains less energy per gallon than gasoline, so a generator usually produces somewhat less power and burns more fuel volume on propane; check your model’s propane ratings. Store cylinders outdoors, upright, and never indoors or in a garage.
How much should you store?
It depends on your generator, your load, and how many hours a day you run it. Our fuel run-time estimator starts from your generator’s spec-sheet run time and your planned hours. Ready.gov suggests planning for outages lasting several days.
Refueling safely
The CPSC and NFPA both say to turn the generator off and let it cool before refueling. Gasoline spilled on a hot muffler can ignite. Refuel outdoors, wipe up spills, and move the fuel can away before restarting.
Quick rules
- Approved cans, outside the living space, away from ignition sources.
- Stabilizer plus rotation.
- Engine off and cool before refueling.
- Check local limits on how much fuel you may store.