Gas vs. propane vs. dual-fuel generators
Each fuel trades off cost, shelf life, cold-weather behavior, and convenience. Here's how to choose.
Gasoline
Cheapest and most available, with slightly higher power output than propane for the same engine. The downside is shelf life: gasoline degrades in months and needs stabilizer for storage, and it can be hard to find during the widespread outages when you need it most.
Propane (LP)
Stores essentially indefinitely, burns cleaner, and is easy to keep on hand in tanks. It produces slightly less power than gasoline and can lose vaporization efficiency in very cold weather. Great for preparedness and infrequent use where fuel sitting unused for a year is common.
Dual-fuel
Runs on either gasoline or propane, switchable at the unit. This is the most flexible option: use gasoline for maximum power day-to-day, fall back to stored propane in an extended outage. The tradeoff is a modest premium on the purchase price.
| Fuel | Shelf life | Relative power | Best for |
|---|---|---|---|
| Gasoline | 3–6 months | Highest | Frequent use, lowest cost |
| Propane | Indefinite | Slightly lower | Preparedness, rare use |
| Dual-fuel | Flexible | Either | Best of both, small premium |
Whichever fuel you pick, size the unit to your real load first — compare fuels at your wattage.
Sources
External figures attributed to the bodies above; wattage estimates on this site are typical planning values to verify against your equipment.