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What size power station do you need to keep a chest freezer running for 24 hours?

Short answer: 1,525 Wh of rated capacity — that's the ~2 kWh — large class. A well-stocked chest freezer holds hundreds of pounds' worth of food.

The math, appliance by appliance

ApplianceAvg drawHours usedEnergy
Chest freezer45 W24 h1,080 Wh
Energy needed per day1,080 Wh
÷ 0.85 inverter efficiency1,271 Wh
× 1.2 headroom (ageing, cold, overrun)1,525 Wh
Recommended: ~2 kWh — large class. Output check: 120 W continuous, 700 W surge.

Fridges and freezers use their average cycling draw for energy and full compressor draw for the output check — that's why the numbers differ from the label.

Adjust this in the calculator See current prices

Quick answers

Can a smaller unit than 1,525 Wh work?
The bare energy need is 1,271 Wh after inverter losses; the extra 20% covers battery ageing, cold weather, and outages running long. A smaller unit works on a good day — this size works on a bad one.
What about output watts, not just capacity?
The station must sustain 120 W continuous and survive a 700 W start-up surge. Nearly every unit in the ~2 kWh clears both comfortably.
Could solar keep this running indefinitely?
Roughly 360 W of panels replaces a day's usage with ~4 hours of decent sun at real-world (75%) efficiency. Half that solar doubles your runtime instead of sustaining it.