What Size Generator for Freezer?
Freezers are efficient and run less than fridges. A 1000W generator can run a chest freezer, and 2000W handles most upright freezers. The key is not starting fridge and freezer simultaneously.
Minimum Size
1000W
bare minimum, tight
Comfortable Size
2000W
recommended
Ideal Size
3000W
room to grow
Total Running Watts
100W
Total Surge/Starting Watts
300W
Generator Sizing Calculator
Additional Custom Load
Running Watts
430W
Surge Watts
1390W
Recommended Generator
2000W+
Includes 25% headroom for reliable operation
Suitable Generator Sizes
Estimated Fuel Usage
* Fuel estimates are approximate. Actual consumption varies by generator model, load, and altitude.
Typical Loads for Freezer
| Item | Running Watts | Surge Watts |
|---|---|---|
| Chest Freezer (7 cu ft) | 80W | 240W |
| Chest Freezer (15 cu ft) | 100W | 300W |
| Upright Freezer (small) | 100W | 350W |
| Upright Freezer (large) | 150W | 500W |
| Total | 100W | 300W |
* Surge watts apply to motor loads during startup. Size your generator for worst-case surge scenario.
Generator Sizing Tips
- •A full freezer stays frozen longer than an empty one
- •Chest freezers are more efficient than upright (cold air doesn't fall out)
- •A well-sealed freezer stays frozen 24-48 hours without power
- •Fill empty space with water jugs - they freeze and act as thermal mass
- •You don't need to run the generator continuously - every 4-6 hours is often enough
Key Considerations
- ⚠Food safety is the priority - keep temp below 0°F
- ⚠Chest freezers are more outage-resistant than uprights
- ⚠Intermittent generator use saves fuel and reduces noise
Alternatives to Consider
- ✓Dry ice to extend frozen time (handle with gloves)
- ✓Portable power station for short outages
- ✓Take food to neighbor or friend with power
Frequently Asked Questions
What size generator for a chest freezer?
A 1000W generator runs most chest freezers easily. They draw only 80-100W running with 240-300W surge. A small inverter generator is quiet and efficient for this use.
How long will food stay frozen without power?
A full freezer stays frozen 48 hours; half-full about 24 hours. Don't open the door. With generator backup, run it 1-2 hours every 4-6 hours to maintain temperature.
Can I run freezer and refrigerator on same generator?
Yes, a 2000W generator handles both easily. Just don't start them simultaneously. Turn one on, wait 30 seconds for compressor to settle, then start the other.