Model
Thor Kitchen RF3621CTDW
Rank #777 means 776 of the 1,000 refrigerator models we track cost less to run each year; the 64th efficiency percentile means it uses less energy for its size than 64% of those models.
What does the Thor Kitchen RF3621CTDW cost to run per year?
The Thor Kitchen RF3621CTDW costs about $100 a year to run, more than most of the 1,000 refrigerator models we track; it ranks #777. It uses 15% less energy than the U.S. federal standard model in its class, which would cost about $115/yr to run, a saving of roughly $15 a year. Size-adjusted, this model beats 64% of refrigerator models we track on efficiency, better than most of its class. This class has no published efficiency-factor figure beyond annual kWh itself, so at 20.3 cu ft (the class spans 1.2 to 31.7), size is the clearest lever we can point to for this model's running cost.
Immediately around it on the leaderboard, the Professional Series PS-FRF172 at $100/yr runs a little cheaper and the Vesta VRF-GREENLAND-36SS at $100/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 Thor Kitchen RF3621CTDW's $100/yr adds up to roughly $1200 in electricity alone, before purchase price or repairs.
Also sold as: Kenmore 897.7551#32#.
By the numbers
The Thor Kitchen RF3621CTDW 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 $100/yr, here is what the Thor Kitchen RF3621CTDW adds up to before purchase price, water, or repairs enter the math.
Left running for a decade at today's US average rate, the Thor Kitchen RF3621CTDW costs about $1000. That is roughly $150 less than a standard model in its class, which would run closer to $1150 over the same ten years.
How the Thor Kitchen RF3621CTDW compares
The refrigerator class we track runs from $8 to $149 a year. At $100/yr, it runs about $36 a year above the class median of $64, and it is about $92 a year more than the cheapest refrigerator to run at $8. Against the US federal standard model for its class at about $115/yr, the Thor Kitchen RF3621CTDW uses 15% less energy.
What drives its running cost
At 20.3 cu ft, the Thor Kitchen RF3621CTDW is a large refrigerator for its class, which spans 1.2 to 31.7 cu ft with a median of 12.6 cu ft, among refrigerator models, bigger capacity is the most common reason a running-cost figure lands on the high side, all else being equal.
- Interior volume. More cubic feet of cold air to maintain generally means a bigger compressor and a higher running-cost figure, even among efficient models.
- Counter depth vs standard depth. Standard-depth models generally offer more interior volume per unit of width than counter-depth models, a tradeoff between built-in looks and cubic feet.
- Compressor technology. How a compressor cycles, full on/off versus a variable-speed inverter design, is one of the biggest hidden differences behind two fridges with similar cubic feet but different running costs.
- Placement and ventilation. Ventilation clearance around the back and top matters more than most owners expect; a fridge starved of airflow runs its compressor longer to hold the same temperature.
Common questions
Is the Thor Kitchen RF3621CTDW cheap to run?
Its $100/yr running cost, rank #777 of 1,000, is above what most refrigerator models we track cost to run, so this is not one of the cheaper picks on electricity alone.
How much does the Thor Kitchen RF3621CTDW cost per month?
About $8.34 a month, which is the $100 annual estimate spread across twelve months at the US average rate of $0.1856/kWh. Your own bill scales with your local electricity rate and how heavily you use it.
How is this running-cost figure calculated?
The formula is annual kWh times price per kWh: 539 kWh from ENERGY STAR times the US average of $0.1856/kWh comes to about $100 a year. It covers electricity only, not the purchase price, water, or installation.
How efficient is the Thor Kitchen RF3621CTDW for its size?
64th 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
Source
ES_1140355_RF3621CTDW_020420260325912_8658525View certified refrigerator listingsENERGY STAR data as of July 2026Thor Kitchen and RF3621CTDW 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.