Model
Stirling S4-100SS
Rank #12 means 11 of the 1,000 refrigerator models we track cost less to run each year; the 72nd efficiency percentile means it uses less energy for its size than 72% of those models.
What does the Stirling S4-100SS cost to run per year?
At $25 a year to run, the Stirling S4-100SS is one of the very cheapest refrigerator models we track, ranking #12 of 1,000, in the bottom five percent on cost. It uses 32% less energy than the U.S. federal standard model in its class, which would cost about $37/yr to run, a saving of roughly $12 a year. Its 72th size-adjusted efficiency percentile is a step ahead of the class median, though not among the very top results. Its listing marks it counter-depth, meaning it sits nearly flush with surrounding cabinets rather than protruding a few extra inches like a standard-depth model; that shallower body usually means less interior volume for the same footprint.
Immediately around it on the leaderboard, the Marathon M4-D250BLS at $25/yr runs a little cheaper and the Stirling S4-D200SS at $25/yr runs a little more, a sense of how tightly models are packed at this point in the ranking. A refrigerator typically stays in service for somewhere around 12 years; over that span, the Stirling S4-100SS's $25/yr adds up to roughly $300 in electricity alone, before purchase price or repairs.
Also sold as: Marathon M4-150SS.
By the numbers
The Stirling S4-100SS 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 $25/yr, here is what the Stirling S4-100SS adds up to before purchase price, water, or repairs enter the math.
Left running for a decade at today's US average rate, the Stirling S4-100SS costs about $250. That is roughly $120 less than a standard model in its class, which would run closer to $370 over the same ten years.
How the Stirling S4-100SS compares
The refrigerator class we track runs from $8 to $149 a year. At $25/yr, it runs about $39 a year cheaper than the class median of $64, and it is about $17 a year more than the cheapest refrigerator to run at $8. Against the US federal standard model for its class at about $37/yr, the Stirling S4-100SS uses 32% less energy.
What drives its running cost
At 5.3 cu ft, the Stirling S4-100SS is a mid-size refrigerator for its class, which spans 1.2 to 31.7 cu ft with a median of 12.6 cu ft, right in the middle of the capacity range, so capacity is roughly a wash compared with the rest of the class.
- Counter depth vs standard depth. Counter-depth models sit flush with cabinets but usually hold less interior volume than a standard-depth model of the same width, which can nudge the per-cubic-foot running cost either way.
- Interior volume. Cubic feet of interior volume is the first thing that scales a fridge's running cost up or down, before compressor quality even enters the picture.
- Compressor technology. Newer variable-speed (inverter) compressors modulate output instead of cycling fully on and off, which tends to use less energy for the same cooling job than an older fixed-speed compressor.
- Placement and ventilation. A fridge pushed tight against a wall or cabinet, or standing next to an oven or in direct sun, works harder to shed the heat its compressor produces, which can push real-world cost above the published figure.
Common questions
Is the Stirling S4-100SS cheap to run?
Yes, relatively. At $25 a year it ranks #12 of 1,000 refrigerator models we track, in the cheaper part of its class to run.
How much does the Stirling S4-100SS cost per month?
Roughly $2.07/mo, spreading the $25/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 134 kWh from ENERGY STAR and multiply it by the US average residential electricity rate of $0.1856/kWh, giving about $25 a year. It is an electricity-only estimate and does not include purchase price, water, or installation.
How efficient is the Stirling S4-100SS for its size?
72nd 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 |
|---|---|---|
| 13 | Marathon M4-D250BLS5.1 cu ft | $25 |
| 12 | Marathon M4-150SS5.3 cu ft | $25 |
| 11 | Marathon M4-100BLS5.3 cu ft | $25 |
| 10 | Marvel MP*D#24-*G#1A4.9 cu ft | $24 |
| 9 | Dometic C60SBI CARE1.7 cu ft | $23 |
Source
ES_1137295_S4-100SS_10032025120439_80246085View certified refrigerator listingsENERGY STAR data as of July 2026Stirling and S4-100SS 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.