How much does your fridge run/use?

Mine is less than 400 and 26 foot

Ours is a Samsung refrig. / freezer, 28 cu ft. from 2012, documented in the device library via HS110 plug:

Sense is estimating 577 kWh / yr, which is not too far from the Energy Star label estimate of 531 kWh / yr.

It does run a lot, so I’ve been wondering if it had any problems. Curiously it uses more electricity when we are away in the winter and the house is colder and it is not opened. I would think it’d be the opposite.

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Your refrigerator probably uses more while your away because it isn’t stocked as well. Freezers work the same way. I keep gallons of water in the freezer to fill the space as that frozen water helps keep it cool and not works as hard.
Try this in your refrigerator, same gallon jugs of water and I’ll wager it makes a difference.
The more empty either are, the more work they have to perform.
The larger power draw your seeing once a day is the defrost heater cycling.
Using the ice maker would use a negligible amount of electricity as the freezing of the water is a byproduct of the compressor keeping the freezer cold. It would add a very small amount for the ice maker heater to dump and the motor to turn the blades to release the cubes.

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I have a 26cu ft Kenmore side-by-side from 2006 and it seems to run ~10hrs (+/-1hr) a day, at 133W. Sense is guestimating 453kWh per year; unfortunately there isn’t any Energy Guide rating for my model so I can’t tell if it’s better or worse. I recently cleaned the coils, which seemed to help lower the run time ever so slightly (but maybe that was all in my head).

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Sam,
That appears to be an urban legend.

I would t believe it had I not seen it. My in-laws has dual residency and spent little time at one home in particular. The freezer at that location would actually have things defrost and spoil when it was near empty versus completely full.
Also, there are supporting articles for both views. I believe the one you provide me a link to doesn’t discount it completely but states the writer has not seen evidence to support it.
Here is one from the department of energy claiming the opposite


Of course the link I provided only applies if you trust the government. :wink:

I have a 30 CuFt new four door Samsung, but have no idea since Sense has not found it. It did find the older 11 year old GE side by side that we have in the garage. Not sure I believe what it is telling me, even though it has about three months of data on it. The states for the last 30 days claim it uses only $18 a year based on 168.4 kWh per year. The avg usage is 123w and it ran 144x for the last month at an average run time of 29m 4s and cost 92 cents for the month. Just seems way too low. Now we only open it about a half dozen times a week and it is packed solid, but it is in a fairly warm garage in Florida.

Maybe Sense isn’t catching every on cycle or maybe it is correct.
Our side by side is opened 944x a month and uses less than 400KWH a year. Sense estimates $37 a year to run it.
Two screenshots. Top is fridge and the bottom is the fridge light showing how many times it’s opened.
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Sam,
Your URL states
“Second, don’t set the temperature colder than necessary. Refrigerators should be set between 36 and 38 degrees Fahrenheit, and freezers between 0 and 5 degrees. Keeping your refrigerator and freezer full can also help regulate the temperature inside. If they aren’t full, try putting bags of ice in the freezer, or pitchers of cold water in the fridge.”

This does not state that keeping it full saves energy. It states that keeping it full can help regulate the temperature.

If you are helping to regulate the temperature by having it full of cold, the compressor has to run less. That translates into less electricity used. Dead air is hard to cool and keep cool.
If you notice that article also states fridge sizing is important. Why is this? Dead airspace!
Keeping it full is more energy efficient.
You can easily test this yourself. Track your usage through a smart plug or sense for a week while it’s full and then do the same with little in it. You will see that when empty, it cycles more often and for longer periods of time.

I agree with Sam on that point. A full fridge will use less electricity. Now, an empty fridge filled with room temperature stuff just to make it full will cost more than an empty fridge. When you open the door, air inside an empty fridge will be replaced quickly by room temp air. That’s why a chest freezer is better that a vertical freezer, cold air stay down.

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Just for the fun of it : Full is not always a good. This picture is a refrigeration tech trying to find why this freezer don’t work. When i saw him i had no choice to take this picture. The plastic bags block air circulation si ice at the bottom will melt. :joy::joy:

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That’s hilarious Marc.
My family was in wholesale food distribution for decades. Those “open air” coolers and freezers you see at convenience stores and grocery stores always made me wonder about operating cost.
Your right about the chest freezer and that’s the only type I will own for that reason. I don’t want to open the door and cold air “fall” out.
What I’ve been doing lately is when my HelloFresh boxes come with ice packs is to put them in the freezer where this too much empty space. They are still pretty frozen even after spending the night with UPS.

With the warmer weather we’ve been having over the past month I’ve seen our power usage going up and have noticed my fridge is running a little more now as well. Also my fridge is on a smart plug so the numbers are spot on.

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Wow @mike_gessner
Yours uses a lot of electricity.
Mine is more efficient than I thought. Something I try to do that most people don’t is clean it every 6 months. I have a brush that is 30” long and a matching vacuum attachment that goes with it. I pull the front cover and brush all of the lint from the coils and vacuum all of it out.
My fridge is also in an enclosed space with less than an inch of airflow on both sides and only 2” on the top.
I keep the fridge at 37 and freezer at 0
Here is mine for comparison

I do the cleaning every few months (at once a year), and yeah there is a lot of dust/pet hair. Now that I have sense I was hoping to see any usage differences, but I can’t. I mean it’s probably still a good idea to-do. On the other hand cleaning the dryer vent pipe (actually replacing it) made a huge difference (20% less run time).

In both my house and my sister’s Sense hasn’t yet identified all “elements” of the refrigerator. I’ve read but cant confirm that there are separate compressors for the refrigerator section and the freezer section, and the defroster hasn’t been identified. Also, I think mine has a variable speed compressor so it hasn’t been identified at all. I think I’ve identified it myself by listening and watching Sense “live”, but it’s still categorized as unknown. I’m hesitant to use one of my HS-110s on the fridge because I don’t want to have the fridge further away from the back wall.

On the subject of whether having water/ice in the compartments will save electricity, I’m not a believer. I do agree that more mass will help regulate the temperature variations, but thermodynamics says that most of the energy for a fridge goes into making up for the heat transfer across the insulated walls, and that’s not affected by the mass of the items in the fridge.

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I would find it highly unlikely that there are separate compressors for fridge and freezer. At least, I’ve never seen one. There is a damper door with an actuator that controls and adjust flow. There are many components to a fridge. Sense has detected my ice maker, door dispenser, compressor and defrost elements. My fridge has about 12 separate components but most are very low wattage and I think what has been identified is all that will be on mine.
Having your fridge or freezer filled versus empty will absolutely save money. My in laws had a couple homes and this is something we tested on their homes where they lived in each part time.

Sub Zero, Thermador, and Miele units have dual compressors. Higher end GE units have one compressor and two evaporator coils - one dedicated to each of the refrigerator and freezer sections. It’s interesting how they’re marketing the feature as a way of keeping the humidity higher in the fridge section than anything to do with energy efficiency. Samsung also has twin evaporators and a single inverter compressor - besides higher humidity in the fridge it also markets “no odor exchange” as a feature. Samsung also has their T Style fridge with two compressors and three evaporators. Here in the U.S. I think they call the feature FlexZone because in addition to a fridge and freezer sections, they have a “Flex” section that you can set to either fridge, freezer, soft freeze, or chill/meat.

LG I think only has one compressor but it’s a digital linear compressor (aka inverter compressor aka variable compressor), so Sense may have a hard time picking it up.

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My Blomberg BRFB1312 has an inverter (variable) compressor which has not been natively detected by Sense. I cautiously put it on a Wemo a couple of months ago and am waiting until the data accumulates before posting to the Device Library.

At one point I thought it was faulty because of the long run cycles but you can see it runs for longer at lower energy levels.

Compressor/fan ramps from about 30-50W and rarely to 65W
Defrost is once every 24hrs, 150W for 20min
Annual usage is somewhat lower than the Energy Label.

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