How Much Does It Cost to Run a Chest Freezer?

A 7 to 10 cubic foot chest freezer uses roughly 20 to 25 kWh a month, which is $3 to $5 at the national average rate. Large 20 cubic foot models use 30 to 40 kWh. Check the EnergyGuide label for your model's yearly figure.

Yes, usually by a wide margin. A manual-defrost chest freezer typically uses half to two thirds of the electricity of a frost-free upright of the same size, because cold air stays in when the lid opens and there is no defrost heater.

A full chest freezer kept closed holds food frozen for about 48 hours, and a half-full one for about 24. Because it averages only 25 to 30 W over a day, a small power station or generator run for an hour every few hours is enough to keep it cold indefinitely.

A typical 7 cubic foot chest freezer draws about 100 W while the compressor runs and up to about 900 W for a moment at start-up. With the compressor running about 30 percent of the time, the average draw over a day is about 30 W (100 W x 0.3).

About 0.72 kWh a day: 100 W x 24 hours x 0.3 duty cycle. At 17.3 cents per kWh that is about 12 cents a day and about $45 a year (263 kWh x $0.173).

No. At about 263 kWh a year, a typical chest freezer uses a little over half of what a full-size refrigerator does (about 460 kWh). It is one of the cheapest ways to store frozen food per cubic foot.

The inverter matters as much as the battery: it must handle the freezer's start-up surge of up to about 900 W. On capacity, a 30 W average load drains a 1,000 Wh station in roughly 28 hours after allowing about 15 percent for inverter losses (1,000 x 0.85 / 30).

In summer, yes. In a garage that reaches 95 degrees the duty cycle can double, taking a typical freezer from 0.72 to about 1.44 kWh a day, or from about $45 to about $91 a year at 17.3 cents per kWh. In winter, check that the model is rated for garage use, since some will not run properly below about 32 degrees.

A chest freezer. A typical chest freezer uses about 263 kWh a year (about $45 at 17.3 cents per kWh), while a typical full-size refrigerator uses about 460 kWh (about $80). An old second fridge in a garage often uses far more than that.

Keep it full, using jugs of water in empty space, since frozen mass holds the temperature between cycles. Set it to 0 degrees F, defrost when the frost reaches a quarter inch, and put it in the coolest spot you have with a few inches of clearance.