Model
Sub-Zero ID-30FI
Rank #309 means 308 of the 622 freezer models we track cost less to run each year; the 11th efficiency percentile means it uses less energy for its size than 11% of those models.
What does the Sub-Zero ID-30FI cost to run per year?
At $74 a year to run, the Sub-Zero ID-30FI sits close to the middle of its class on cost, ranking #309 of 622 freezer models we track. It uses 10% less energy than the U.S. federal standard model in its class, which would cost about $82/yr to run, a saving of roughly $8 a year. Its 11th size-adjusted efficiency percentile is well below the class median, worth weighing against the raw cost figure above. At 5.1 cu ft, it is a small 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 Wood'S WUF140W at $74/yr runs a little cheaper and the Bosch B18IF905SP at $75/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 Sub-Zero ID-30FI's $74/yr adds up to roughly $1036 in electricity alone, before purchase price or repairs.
By the numbers
The Sub-Zero ID-30FI 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 $74/yr, here is what the Sub-Zero ID-30FI adds up to before purchase price, water, or repairs enter the math.
Left running for a decade at today's US average rate, the Sub-Zero ID-30FI costs about $740. That is roughly $80 less than a standard model in its class, which would run closer to $820 over the same ten years.
How the Sub-Zero ID-30FI compares
The freezer class we track runs from $25 to $120 a year. At $74/yr, it runs about $1 a year cheaper than the class median of $75, and it is about $49 a year more than the cheapest freezer to run at $25. Against the US federal standard model for its class at about $82/yr, the Sub-Zero ID-30FI uses 10% less energy.
What drives its running cost
At 5.1 cu ft, the Sub-Zero ID-30FI is a small freezer for its class, which spans 1.1 to 23 cu ft with a median of 13.8 cu ft, less capacity to service is usually the first reason a running-cost figure lands on the low side, before efficiency even enters the picture.
- 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 Sub-Zero ID-30FI cheap to run?
It is about average. At $74 a year it ranks #309 of 622 freezer models we track, close to the middle of its class on running cost.
How much does the Sub-Zero ID-30FI cost per month?
Roughly $6.17/mo, spreading the $74/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 399 kWh from ENERGY STAR and multiply it by the US average residential electricity rate of $0.1856/kWh, giving about $74 a year. It is an electricity-only estimate and does not include purchase price, water, or installation.
How efficient is the Sub-Zero ID-30FI for its size?
11th percentile once size is factored in, a fairly typical result for the class.
Cheaper to run in the same class
| Rank | Model | Cost/yr |
|---|---|---|
| 308 | Wood'S WUF140W14.1 cu ft | $74 |
| 307 | Wood'S WUF140SL14.1 cu ft | $74 |
| 306 | Fisher & Paykel RS24F*E*12.6 cu ft | $74 |
| 305 | Ge FUF14DL****14.1 cu ft | $74 |
| 304 | Vitara VLUF1701ECE14 cu ft | $73 |
Source
ES_0031863_ID-30FI_07032014112231_2742900View certified freezer listingsENERGY STAR data as of July 2026Sub-Zero and ID-30FI 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.