On backup power, chest freezers are generally manageable loads if your inverter or generator can absorb startup surge.
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Quick Answer
Expect 80 to 250 running watts, 500 to 1,500 starting watts, and roughly 1.3 to 4.0 kWh over a 24-hour outage day depending on conditions.
Backup-Power Notes
During outages, limiting door openings can materially reduce runtime. If multiple compressor loads restart together after power returns, temporary peaks can stack.
Typical Ranges
| Size | Running Watts | Starting Watts | 24h Outage Energy |
|---|---|---|---|
| Small | 70 - 130 W | 400 - 800 W | 1.2 - 2.2 kWh |
| Medium | 100 - 180 W | 600 - 1,100 W | 1.8 - 3.1 kWh |
| Large | 140 - 260 W | 900 - 1,600 W | 2.4 - 4.0 kWh |
Practical Example
A freezer that averages 140 W during an outage day uses 3.36 kWh. If your battery has 5 kWh usable, this single load can consume most of it.
Related: How to Calculate Total Home Backup Load.
FAQs
Should I prioritize freezer over other loads?
Often yes, especially in longer outages where food preservation is critical.
Can a 2000W generator run it?
Commonly yes, but check surge and concurrent loads.
Is nighttime usage lower on backup?
It can be, especially in cooler ambient conditions and with fewer door openings.
CTA
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