Model
Koolatron KKUF21-*
Rank #463 means 462 of the 622 freezer models we track cost less to run each year; the 89th efficiency percentile means it uses less energy for its size than 89% of those models.
What does the Koolatron KKUF21-* cost to run per year?
Do the math and the Koolatron KKUF21-*'s $91/yr puts it at rank #463 of 622, on the pricier side of the class. It uses 10% less energy than the U.S. federal standard model in its class, which would cost about $102/yr to run, a saving of roughly $11 a year. Adjusted for its size, it is more efficient than 89% of freezer models we track, a strong result once size is taken into account. At 21 cu ft, it is a large freezer for the class, which runs 1.1 to 23 cu ft; size and efficiency are the two levers behind the figure above, and this dataset does not carry a separate efficiency-factor column for this class.
Immediately around it on the leaderboard, the Kenmore KKUF21-* at $91/yr runs a little cheaper and the Koolmore KM-RUF-21S at $91/yr runs a little more, a sense of how tightly models are packed at this point in the ranking. A freezer typically stays in service for somewhere around 14 years; over that span, the Koolatron KKUF21-*'s $91/yr adds up to roughly $1274 in electricity alone, before purchase price or repairs.
Also sold as: Arctic Wind AUFW210ETH-LK.
By the numbers
The Koolatron KKUF21-* normalized against its whole class, so each figure means something.
What it costs you over time
Running cost is an every-year number, so it compounds. At $91/yr, here is what the Koolatron KKUF21-* adds up to before purchase price, water, or repairs enter the math.
Left running for a decade at today's US average rate, the Koolatron KKUF21-* costs about $910. That is roughly $110 less than a standard model in its class, which would run closer to $1020 over the same ten years.
How the Koolatron KKUF21-* compares
The freezer class we track runs from $25 to $120 a year. At $91/yr, it runs about $16 a year above the class median of $75, and it is about $66 a year more than the cheapest freezer to run at $25. Against the US federal standard model for its class at about $102/yr, the Koolatron KKUF21-* uses 10% less energy.
What drives its running cost
At 21 cu ft, the Koolatron KKUF21-* is a large freezer for its class, which spans 1.1 to 23 cu ft with a median of 13.8 cu ft, size is usually the single biggest lever behind a running-cost figure, and at this end of the range there is more capacity to service, which tends to push the number up.
- Interior volume. Cubic feet of frozen storage is the first lever behind a freezer's running cost, ahead of insulation or defrost type.
- Insulation and defrost type. Two freezers of the same size can differ meaningfully on running cost based on insulation quality and whether they run an automatic-defrost heater.
- Chest vs upright design. Chest freezers open from the top, so cold air, which sinks, stays inside when the lid opens; upright freezers lose more cold air per door opening for a similar capacity.
Common questions
Is the Koolatron KKUF21-* cheap to run?
Not especially. At $91 a year it ranks #463 of 622 freezer models we track, in the pricier part of its class to run, though its size and features may still justify that for your needs.
How much does the Koolatron KKUF21-* cost per month?
Roughly $7.61/mo, spreading the $91/yr estimate evenly across twelve months at $0.1856/kWh. Actual monthly bills swing with your rate and usage pattern.
How is this running-cost figure calculated?
We take the model's published annual energy use of 492 kWh from ENERGY STAR and multiply it by the US average residential electricity rate of $0.1856/kWh, giving about $91 a year. It is an electricity-only estimate and does not include purchase price, water, or installation.
How efficient is the Koolatron KKUF21-* for its size?
89th percentile once size is factored in. That means its size-adjusted efficiency is a real factor in the running-cost figure above; its capacity plays a large role too.
Cheaper to run in the same class
| Rank | Model | Cost/yr |
|---|---|---|
| 475 | Kenmore KKUF21-*21 cu ft | $91 |
| 474 | Kenmore 111.2220291021 cu ft | $91 |
| 473 | Insignia NS-UZ21WH0-C*21 cu ft | $91 |
| 472 | Insignia NS-UZ21WH021 cu ft | $91 |
| 471 | Insignia NS-UZ21***21 cu ft | $91 |
Source
ES_0015649_KKUF21-*_10252023115957_80185595View certified freezer listingsENERGY STAR data as of July 2026Koolatron and KKUF21-* are used here for identification only and are not endorsements. Figures are computed by WattWise Labs from public ENERGY STAR data, not measured in our own lab.