A chest freezer typically draws about 80 watts while running (roughly 50-150 W) and uses about 0.6 kWh a day. The compressor needs a short starting surge, listed as up to about 2,200 watts on generator charts.
- Running watts
- 80 WTypical; 50–150 W across models
- Starting watts
- 2,200 WGenerator charts list about 2,200 W for refrigerator/freezer…
- Per day
- 0.6 kWh24 h of use, cycling
- Current
- 0.7 AAt 120 V while running
Figures checked against DOE, ENERGY STAR and manufacturer data on . Your model's label is the final word.
Watts by model and setting
Most chest freezer models draw between 50 and 150 W while running; a typical one draws about 80 W. ENERGY STAR says certified chest freezers use about 215 kWh a year (~0.59 kWh/day); 80 W x 24 h x 0.3 is about 0.58 kWh/day.
- Capacity: 5 cu ft models use much less than 15-20 cu ft models
- Location: hot garages make the compressor run more
- Manual-defrost chest freezers use less than frost-free models; let frost build-up stay under 1/4 inch
- ENERGY STAR models are at least 10% more efficient than the federal minimum
Running a chest freezer on a generator or power station
- Generator: at least 80 running watts and 2,280 starting watts (running plus the 2,200 W start surge, the cautious way to size it). Check both numbers on the spec sheet. A generator rated 3,000 W or more covers it with room to spare.
- Power station: continuous output of at least 80 W and a surge rating that covers about 2,200 W. Pure sine wave output is the safe choice for motors and electronics.
| Power station capacity | Estimated runtime |
|---|---|
| 500 Wh | 17.7 h |
| 1,000 Wh | 35.4 h |
| 2,000 Wh | 70.8 h |
| 3,000 Wh | 106.2 h |
Based on 24 W average draw (running watts × duty cycle) and 85% usable capacity.
- A full chest freezer holds temperature for about 48 hours unopened, so it can be powered in shifts during an outage
- Make sure the generator or power station surge rating covers the compressor start
- Pure sine wave output is recommended for compressor motors
- Run a gas generator outdoors only, at least 20 feet from doors, windows and vents; carbon monoxide from generators kills. Connect appliances with heavy-duty extension cords or a professionally installed transfer switch, never by backfeeding.
Add it to the generator calculator
Questions people ask
What size generator do I need for a chest freezer?
Running watts are low, so even a 2,000 W inverter generator handles one easily along with a refrigerator, provided you start them one at a time.
Is a chest freezer more efficient than an upright?
Usually yes. ENERGY STAR estimates about 215 kWh a year for certified chest freezers versus about 395 kWh for uprights, because cold air stays in when the lid opens.