Comparing the power consumption of a 30 year old refrigerator to a new one

https://ounapuu.ee/posts/2025/10/14/fridge-power-consumption/

by furkansahin • 9 months ago

217 228 9 months ago

abraxas• 9 months ago

Energy Star appliances started to show up circa 1995 so there may have been comparably efficient fridges back then.

stereo• 9 months ago

The author is in Estonia. Appliances in the European Union have different energy standards and labels, and run on different voltages, so you don’t ever see Energy Star fridges there.

Estonia joined the EU in 2004, and I don’t know what the energy labelling on appliances was like before then.

zikduruqe• 9 months ago

According to Project 2025, we won't ever see them again.

https://static.heritage.org/project2025/2025_MandateForLeade...

"Eliminate energy efficiency standards for appliances. Pursuant to the Energy Policy and Conservation Act of 1975 as amended, the agency is required to set and periodically tighten energy and/or water efficiency standards for nearly all kinds of commercial and household appliances, including air conditioners, furnaces, water heaters, stoves, clothes washers and dryers, refrigerators, dishwashers, light bulbs, and showerheads. Current law and regulations reduce consumer choice, drive up costs for consumer appliances, and emphasize energy efficiency to the exclusion of other important factors such as cycle time and reparability."

https://tonko.house.gov/uploadedfiles/project-2025-fact-shee...

someperson• 9 months ago

Since after 3 years you're beyond the break-even point due to energy use, the old refrigerator should be disposed of rather than given away.

By keeping it in service, it's making somebody poorer. Especially since the person receiving the free 30 year old power hungry refrigerator and keeping it for a decade is the least likely to afford a replacement.

Somebody already disadvantaged will eventually be stuck with structurally higher bills and find it harder to save due to this.

Those that's not your problem it's more a government policy problem.

avmich• 9 months ago

It would be interesting to hear your comparison to counterarguments to this. Can you explain why these arguments are more important?

emtel• 9 months ago

Poor people can make their own decisions about whether to use an old fridge or not. They know much more about their own situation than you do. You are not well situated to make these sorts of decisions for them.

Johnny5552• 9 months ago

But do they? Does the person taking on that broken refrigerator know that it has a flaw that makes it consume so much electricity that in 3 years the power use alone would cost more than buying a brand new refrigerator?

(ok, in this case they gave it to someone that needs a temporary 'fridge during renovations, so it's kind of a moot point, they aren't just giving it to "poor people")

bloomingeek• 9 months ago

There's an old expression that I actually lived out: "Poor people have poor ways."

When I was living well below the poverty level, I used whatever resource that was available as long as it was legal. I was given a chest type freezer that was made somewhere in the early 60's, but was in good working order, since it was owned by a person in the HVAC field. It wasn't very efficient, but I needed the freezer space. (Since we didn't have air conditioning, I could afford the electric usage.) Most poor people make decisions based on whatever works, not if it's the best option, because of the lack of money.

Manfred• 9 months ago

From the article:

as a stopgap until they get further with renovation work

I assume they know what they are getting into.

Theodores• 9 months ago

As another person has noted, this wasn't quite the scenario - they had renovations, but you know that now.

I had to renovate a kitchen a while ago and I got into the habit of living without a fridge or a freezer. It came as a surprise that this was possible, and the article is interesting because I now know how much money is saved. I can compare this to food wasted due to a lack of refrigeration, and, I am still seeing the advantages of no fridge. Such heresy!

It depends on what you eat, but I don't have time for most things that need to go in the fridge. If it isn't in the fridge at the supermarket then it doesn't need to be in the fridge at home is the general rule. Oddly I have lower food waste with no fridge, but there are annoyances such as not being able to buy a big bag of (say) carrots, and having to resupply twice a week. On the whole though, my food is a lot fresher than when I had a fridge, plus I have upped my nutrition game to not have this food morgue of things that 'want to kill me'. I joke, but there were a lot of ready meals, sticky puddings and much else that might as well been 'raw trans fats'. I went from this to a jute bag, which seems to keep most vegetables fresh enough for long enough.

What is also interesting about fridges is how quickly they turn into some cave of mold even if they are kept nice and clean. Turn that electricity off, take everything out, and, unless you keep the door open, some true horrors will be found in there a week later.

In the article this was not a like for like efficiency test by any stretch of the imagination. Over time it is the door seal that goes and, if that isn't tight then it will just be sucking moisture out of the air to make a huge ice block, hence compressor on the whole time.

The next problem is that some fridges have vents with fans in them, sometimes forward facing at the base. These get to collect lots of dust, hair and other debris, making them ineffective.

Despite these test methodology issues, in the real world people will be replacing an old fridge that has a dodgy seal with a new fridge that works as the manufacturer intended.

Regarding your point of the poor, do you have any idea how many people in the UK do not have a fridge, or access to one? Allegedly it is in the millions, which I find hard to believe, but have not dismissed out of hand. There are so many people living in sub-standard rented accommodation in a shoebox sized 'studio flat' (or worse). Proper housing is required before these people can get a fridge. The UK is allegedly a first world country, but with huge inequalities when it comes to property and income.

I suspect that in much of the world not having a fridge is no big deal, if you are living off the land rather than processed foods and processed animal products then why would no fridge be hardship?

It is amazing how many assumptions there are regarding fridges, the need for them and whether life is 'disadvantaged' without one. Until relatively recent times nobody had fridges yet we somehow survived, albeit with some mortality issues.

echelon_musk• 9 months ago

Comparing the power consumption of a [broken] 30 year old refrigerator to a brand new one

throw10920• 9 months ago

Yeah, the title is misleading. The article says that one of the compressors on the old one was running constantly - if you applied the same failure mode to the new refrigerator, the difference would be significantly less.

quickthrowman5• 9 months ago

I would expect a refrigerator that has EC motors running the compressor(s) and fan(s) to be around 2-2.5x as efficient as one with fixed speed motors, based on what I know about variable frequency drives and three-phase induction motors. For those, 80% speed uses 50% of the power, 63% uses 25% of the power. For an 1800 rpm motor that is 1440 rpm and 1134 rpm. VFDs work well for most applications with variable torque (fans and pumps), but applications requiring constant torque (saws, grinders, etc) are better served by fixed speed starters.

sandworm1012• 9 months ago

Given modern minimalistic build standards, the modern compressor would probably overheat and fail if run continuously 24/7. I am reminded of the old simpsons bit where they make a tent in front of the refrigerator.

https://youtu.be/1t9BdMuzV64

OJFord• 9 months ago

It's still functional though, the point is comparing 'keep running the old tired one' vs 'replace with new', not 'how well were they made then vs now'.

roughly• 9 months ago

I feel like a more appropriate - or at least a more interesting - comparison would be “fix the old one” vs “replace with new.” Replacing an old broken product with a new unbroken one is changing two variables, not one.

Now, if the author would like to break their New refrigerator and report back, I’ll take it as an interesting result.

courseofaction• 9 months ago

Save us dang

tobyhinloopen2• 9 months ago

"Broken"? It kept things cold.

roflchoppa• 9 months ago

I really want to know the power usage of the old fridge after it was fixed. :(

cogman103• 9 months ago

My assumption, probably pretty close to the new fridge.

Very little has changed in fridge tech in 30 years besides them getting cheaper and breaking easier.

saltcured4• 9 months ago

For a fair comparison, they should measure a modern fridge when it misbehaving and running its WiFi and GPU constantly

simpsond• 9 months ago

Is that true though? Better coolants, inverters / variable speed / scroll /swing compressors, insulation and mfg, etc. maybe for residential it’s less impactful, but refrigeration in general has better efficiency than 30 years ago.

parpfish• 9 months ago

have there been improvements to the insulation? given how good high-end coolers are now, i'd assume that there's been something with the non-mechanical parts that could have improved

SoftTalker4• 9 months ago

The old fridges that didn't self-defrost are probably the most reliable. The only moving part is the compressor. No fans, no heaters, and fairly quiet. But the freezer compartment will ice up especially in humid climates and must be periodically defrosted which is a bit of a PITA.

shellfishgene2• 9 months ago

Here is some general data: https://appliance-standards.org/blog/how-your-refrigerator-h... Data is shown only up to 2014, modern ones use more like 300-400 kWh/year.

FabHK• 9 months ago

Why talk about 2.6 kWh/day (power*time/time = energy/time = power) when there is perfectly fine unit for that, namely the watt?

2.6 kWh/day = 2.6 kWh/24h = 108 W, on average.

snet0• 9 months ago

I've had this thought before, when seeing labels that talk about kWh/day. The answer is very simple: you pay per kWh. When people want to know power efficiency, what they really want to know is "how much will this cost me to run?". That answer is most easily expressed in kWh per unit time.

kitten_mittens_• 9 months ago

In the US, at least, there are some utilities that charge based on maximum kW (demand) and total kWh used (energy). ComEd in Chicago is a utility with a demand rate plan option.

thesimon• 9 months ago

when seeing labels that talk about kWh/day

That's at least kinda reasonable. I'm always amused when I see TV energy labels that state

xx kWh/1000h

tialaramex• 9 months ago

Also giving an averaged power drain would be misleading. If the device uses 2.4kW but only for half an hour per day, that's not a 50W device as far as cabling, fuses and other electrical considerations.

neutronicus• 9 months ago

Because the most familiar anchor for scale is the monthly meter reading, which is in kWh.

madaxe_again• 9 months ago

Watts measure power, kWh measure energy - and they are a more convenient unit than J.

Marsymars4• 9 months ago

If you have natural gas connection, you can be charged for both kWh and GJ on the same bill!

dogsgobork• 9 months ago

Electric bills aren't calculated by the Watt, you pay per kWh. The expected cost of running the fridge is the salient information.

tomrod2• 9 months ago

0.108 x 168 hours/wk x 4.4 wks/month gives a good approximation for kwh/month. Demand over time gives consumption just fine.

A 75% drop is nice and much improved.

themafia2• 9 months ago

Yet the service into my home and each individual circuit has a maximum on received power so the Watt is usually more pertinent anyways. Taking an average Watt usage value and extrapolating that into kWh/month is both incredibly easy and completely standardized.

ASomniphobeHere• 9 months ago

Possibly because it gives better intuition for the approximate cost per unit of time. Similar to how fuel consumption can be written as volume/length = area, but is still usually presented in the former way, since that shows the actual amount of resource being consumed.

Ekaros2• 9 months ago

It is bit too derived unit. But on other hand it does make calculations pretty simple. Say 0.14 per kWh and then cost in month is simple multiplication 2.6300.14 . Or a year is 2.63650.14...

bee_rider• 9 months ago

Although this is totally informal, in a normal conversation if somebody gives me the wattage of a device, I assume they are peak power draw. For kWh/day, I assume they’ve accounted for some reasonable duty-factor.

manwe1503• 9 months ago

I thought watt is a DC unit, so often avoided for AC measurements, since it is ambiguous which watt you are talking about, and the device is always consuming more or less than the average, and very rarely consuming that actual amount. Often the alternate unit is called VA, even though that too seems like a watt

BenjiWiebe2• 9 months ago

Watts work fine for AC - multiply your RMS voltage by current. The RMS takes care of the fact that AC isn't steady like DC.

VA (takes power factor into account) is relevant for sizing transformers, breakers, wiring, etc but usually only affects your bill if you are a large industrial customer.

stephen_g• 9 months ago

Because that's not what they're interested in! Really what they care about is that the fridge is consuming about 9.36 MJ/day, because really kWh is just a convenience unit for joules. But since everyone gets charged in kWh that's the unit they use.

agsamek• 9 months ago

My new Bosch 2020 refrigerator broke down after 3 years of usage. Coolant leakage. Not repairable due to the foam direct injection.

anjel2• 9 months ago

Todays appliances are built, by design, to break fast these days. So whether old (operating costs) or new (foreshortened lifespan) your appliances cost you more.

https://www.nytimes.com/wirecutter/reviews/modern-appliances...

(https://ghostarchive.org/archive/KGf2Z)

trenchpilgrim2• 9 months ago

There are still some repairable brands. GE'a basic appliances (and their budget subbrands like Hotpoint) are a standout with excellent availability of parts and service data. A hotpoint electric range can be fixed by any homeowner with a screwdriver.

jeffbee• 9 months ago

That article does not seem to support in any way the statement that appliances are intentionally designed for short lifespans.

infecto• 9 months ago

Was not immediately apparent in article but I did not read the whole thing. Beyond general repairability the other issue to me is the cost of labor. In Vietnam I can get near anything repaired because the cost of labor is so darn cheap. In America it makes no sense to be paying $100/hour usually minimum two hour repair plus the cost of the part.

I am ok with generally with having less ability to repair but I do wish more cities and companies and trade in programs for proper recycling.

axiolite4• 9 months ago

Neither the article nor the linked sources even attempt to prove that modern appliances are less durable or having more issues than old appliances.

It seems to be just complaining about "computer circuit boards" in appliances, much the way people did about electronic ignition in cars, despite actually resulting in a huge increase in engine reliability because solid state has so very little to fail.

I mean, maybe people throw out a perfectly working toaster when it can't connect to Wi-Fi anymore, (or take their car to the dealer when their entertainment system acts-up) but that's not an actual reliability issue, IMHO.

tobyhinloopen2• 9 months ago

My Samsung refrigerator runs still great after 12 years.

aurizon• 9 months ago

The comments are well done and I am impressed. I would add the maker of the new one, partly as a tribute to them as well as gathering feedback from others. The fact that one compressors runs 24/7 might indicate it has failed to on 24/7 - also the ice block also says this? Thus a replacement thermostat might well reduce the KwHr used by the 24/7 operation. Looking up the model on youtube for thermostat repairs might help the new owner repair it and get a few more years, although an older less efficient unit, with a repaired thermostat it might not run 24/7 and use fewer KwHr?

woile• 9 months ago

A 21 kWh/month it's 252 kwh/annum (I guess?), which is around energy label E in the new EU energy labels.

If you go for energy label A, some fridges have 101 kWh/annum, which is more than half less! I haven't seen many, and they are usually very tall, but hopefully we can see more and more in the future.

tgv• 9 months ago

They're freaking expensive, though. I just replaced a (probably) 25 year old fridge by one with a D label. The difference with a C or E label is small in energy use. I do notice that the exterior gets really less warm than the old model. I don't think it would have qualified as an E.

BTW, if I'm not mistaken, the energy label depends on the function. So 250kWh/yr could be (much) lower than E when the volume is smaller.

gdelfino01• 9 months ago

New ones break quickly and then consume zero energy. So then you buy an even newer one without caring at all about the emissions to buy the new one and to get rid of the old one. And then feel good to be "saving the planet" because you have a super efficient fridge and repeat the cycle.

userbinator5• 9 months ago

jeroenhd3• 9 months ago

Depends on what kind of fridge you buy. If you buy one for the price of a fridge in the "good old times" that doesn't come loaded with useless features, they last just fine.

A lot of degrading quality in household appliances is the result of consumers buying the cheapest products that'll get the job done. Many people would rather risk having to buy two €600 fridges rather than buying one €1200 fridge (freezer sold separately of course).

I can get a full fridge+freezer combination delivered to my home for €380. Of course that won't last as long as the €1200 equivalent from forty years ago, back when that was the normal price for a fridge.

ternus3• 9 months ago

Totally fine to choose as the author did, but for others who might face a similar choice: repairing a thermostat in a fridge is dramatically easier than fixing almost anything in a dishwasher. I did that with my fridge - cost <$20 for the part and maybe 30 minutes of work. Your (EU) kilometrage may vary.

I suspect the power savings would be much less dramatic with a fixed thermostat.

analog313• 9 months ago

Indeed, been there. Just getting the dishwasher out of its cubby hole is a major effort, and involves dealing with not just the wiring but the hoses too. And if it's an older house, chances are good that the dishwasher had to be crammed in with a certain amount of hacking, cussing, and persuasion.

The fridge rolls out into the room on its own wheels.

aidos• 9 months ago

Amen. I put my dishwasher in myself so I get to curse myself for that hacking.

Worst was sourcing the parts though. Getting the thing out, effectively getting it up on blocks to run it and see the issue was hard work. Getting the specific totally non-standard o-ring size out of the manufacturer was impossible. In the end I resorted to siliconing but I just cannot dump something like that over a 5c part.

ternus3• 9 months ago

Many dishwashers are supposed to be wood-screwed into the surrounding cabinets! Recently installed one for a friend and was surprised to see that instruction.

Meanwhile, with the exception of ice makers/water dispensers (1/4 PEX), fridges don't have to deal with hoses for the most part. So much easier IME.

RandomBacon• 9 months ago

Unless the fridge is sitting on the subfloor/slab and a floor was built around the fridge, blocking it in.

kleiba• 9 months ago

This must be dependent on your country's customs, I suppose. I've taken out dishwashers quite a few times and it was actually fairly easy. No wheels, true, but cables and hoses were never much of a problem in my case.

acomjean• 9 months ago

My partners bought a house with a dishwasher. Apparently it was installed, then a new floor put in raising it about an inch effectively locking the dishwasher in place. Removing it involved removing the counter above (it needed replacing..) but your comment brought back some memories(lots of cussing)

dawnerd• 9 months ago

Depends. My last fridge the thermostat went bad and it couldn’t be fixed because they embedded the entire thing into the foam. Terrible design. Was a whirlpool.

rootusrootus4• 9 months ago

That's similar to what sent my last Samsung fridge to its next home. Samsung apparently had some problems with wire movement in the door hinge, so they changed the design and embedded the wires in glue/foam/whatever. So now if you have a problem with those wires, which happens because it's a hinge ... you get to replace the whole door at least. Turns out to be an expensive pain in the ass if the fridge is more than a few years old, it was more time- and cost-effective to get a new fridge at that point.

criddell2• 9 months ago

I just replaced the drain pump and motherboard on my GE dishwasher and it was super easy. Everything was easy to access and all the major parts had a QR code on them making parts lookup idiot proof.

When the parts showed up they came with all the clamps and other replacement hardware that I didn’t even know I needed.

ternus3• 9 months ago

Also: if you find ice forming in your fridge, or uneven cooling inside, it may be due to a clogged drain tube. This was the root cause of my fridge breaking: tube in the back clogged -> condensation backed up around the evaporator coils -> froze solid -> blocked circulation fan -> incorrect thermal readings, warm/frozen spots in fridge.

dlcarrier3• 9 months ago

I had one with a fan inside it that died, to similar effect. I didn't even know it used a fan to recirculate the air, until it didn't.

axiolite4• 9 months ago

I've found cheap after-market thermostats to have short lifetimes... Original lasted 20 years... Replacement started misbehaving in just 2 years.

So now my policy is to retrofit all old refrigerators with digital STC-1000 thermostats. A bit more work to cut out some plastic, split the hot wire and tap into a neutral wire (easy enough to follow the bulb) but cheaper, super reliable, and gives very consistent and highly controllable results.

Two such upgraded refrigerators are still working without an issue several years later. Though both required replacing the relay (with a solid state relay/capacitor unit) at about the same time, and one after replacement of the evaporator fan motor due to noise issues.

cl3misch• 9 months ago

Do you have a guide or reference to follow?

dlcarrier3• 9 months ago

I've found US dishwashers pretty easy to fix, but Korean and German ones can be a bit more of a pain, and these are the ones built for the US market. I've heard that European models often have water softeners built in.

rootusrootus4• 9 months ago

Yeah I was wondering if there was perhaps some regional differences. The one time I did a DIY fix of my dishwasher I was pleasantly surprised with how easy it was. They're largely very simple devices, and aside from a couple screws to keep them from tipping, they slide right out of the opening they're in.

[...] German ones can be a bit more of a pain

I did replace my dishwasher a few years ago with a Bosch. Uh-oh!

userbinator5• 9 months ago

Looking at their designs, this seems to be the case with other white goods too; I suspect it's because US designs are relatively old and simple since they were among the first, while foreign designs are more highly space- and cost-optimised at the expense of repairability and possibly robustness.

shellfishgene2• 9 months ago

All German ones have water softeners I think, also most modern ones have a large flat water tank at the side that acts as a heat exchanger and condensation surface, and also saves water from the last rinse cycle to use in the first wash cycle the next time it's turned on.

barbazoo• 9 months ago

It takes a long time getting to know your dishwasher but my 2014 model was actually not that hard to debug and fix. Need to be able to source the parts of course. I was surprised how repairable it was. Will watch out for it when I need to buy another one.

ctrlp• 9 months ago

Regardless of efficiency, it is very difficult to find a newer refrigerator whose compressor doesn't emit a very irritating high pitched whine almost continuously.

jrmg2• 9 months ago

Personal pet level is that it’s so hard to get information on the noise level of appliances.

We’ve recently moved, and our new house’s crawl space has a Santa Fe dehumidifier in it that seems SO LOUD at night. I don’t think it’s broken - it’s just a compressor and fan with no engineering put into keeping them quiet. If I could get one that was as efficient and well built, but I knew would be quiet, I’d replace it in a heartbeat - but manufacturers don’t advertise noise levels.

Surely I can’t be the only one who’d pay substantially more for an appliance that was guaranteed to be quiet?

reddalo• 9 months ago

it’s so hard to get information on the noise level of appliances

It's super easy if you live in the European Union, thanks to the Energy Label [1] which is mandatory on every appliance.

[1] https://energy-efficient-products.ec.europa.eu/ecodesign-and...

bob1029• 9 months ago

I would try plugging a simple induction motor into the refrigerator circuit to see if it also makes a weird noise. It's possible you have a problem with the wiring itself (loose neutral, etc.).

I've never had issues with HF noise out of a refrigerator. It's always been the opposite kind of noise that has been a problem.

silvestrov• 9 months ago

My Miele hums with so low frequency that it sounds like a truck is passing by.

userbinator5• 9 months ago

The newer compressors are smaller so they cost less, but are run faster to pump at the same rate. Many old hermetic compressors used a 4-pole 1500/1800RPM motor, then they became a 2-pole 3000/3600RPM, and the newest VFD/inverter motors can go even faster.

prmoustache3• 9 months ago

The dramatic things with refrigerators is that in most countries people will install them in the kitchen for obvious practicality reasons, which is often also the hottest room of the house/appartment due to ovens, stoves and spending a significant amount of time there. If you think of it, it is bonkers that we put a device meant to keep stuff cold in what is a heated place in northern countries. Some hold houses and building used to have non heated dedicated rooms meant to keep food at a lower temperature naturally in winter but this has pretty much disappeared.

OTOH I live in a coastal city in south of Spain and every time I read a label that said food shouldn't be in a fridge but kept in a fresh and dry storage I ask myself where the eff should I store it there is no place like that unless I am running aircon 24/7 which I certainly won't do.

JumpCrisscross• 9 months ago

kept in a fresh and dry storage I ask myself where the eff should I store it

Your mountain home. (I'd hazard a guess that many such products come from the interior versus humid coasts.)

rz2k• 9 months ago

I Suppose heating fuel is cheaper, or household heat pumps are more efficient, but all of the energy consumed by running the refrigerator becomes waste heat in the same room you are trying to heat. That seems superior to the refrigerator heating a room where the waste heat isn’t useful.

fifilura4• 9 months ago

Where do you store your wine? (Only half kidding, but I am sure you have solutions like this in Spain)

prmoustache3• 9 months ago

well I don't have one, I rarely ever drink wine at home, but there are dedicated devices for that, I think they are called wine cabinets in english? They could be used to store other things indeed. I have never looked at the energy consumption of these things.

Aurornis• 9 months ago

The ambient temperature differential between the kitchen and other rooms in a house is minimal on average. There’s nothing bonkers about putting the refrigerator in that space. Even a hypothetical 20F temperature rise during an hour long cooking session is basically negligible for the efficiency of a refrigerator that is cooling 24/7.

Putting the refrigerator in an unconditioned space wouldn’t be as big of a win as you think because every time you open the door to the unconditioned space you’re letting cold air into the house. Twice per refrigerator visit all day long adds up.

In the winter you actually benefit from having the refrigerator in your conditioned space because the waste heat goes toward heating your house. It would be lose-lose to put it outside of the house in a cold location.

zoeysmithe• 9 months ago

The fridge box is fairly insulated. Temps in my home are consistent all over plus or minus a couple degrees. I think you've overstating the case a lot here. Even with the oven running it doesnt seem to affect the fridge too much. Heck in a lot of warmer climates people leave a spare fridge outside where its battling non-climate controlled air.

In the winter your fridge's waste heat is warming up your kitchen, so if anything, its a bit of a bonus those months.

The only thing I think we could do with fridges is put in a system that pulls cold air in during the winter but that's sawing holes into brick and yet another thing to worry about in regards to mold, critters, moisture, filters, fans, etc. Its just not worth the effort or cost.

guerby• 9 months ago

I got a rated "A" for one year, this model (256 liter fridge + 122 liter freezer) :

https://eprel.ec.europa.eu/screen/product/refrigeratingappli...

Rated for 113 kWh/year

I left a powermeter on it for one year and got 130 kWh.

It's amazing that the average power consumption is less than 15 Watt.

sitharus• 9 months ago

I (well, my landlord) replaced a similarly old refrigerator last year. The thermostat was fine, it had developed a very slow gas leak and the charge had dropped enough that it was freezing rather than cooling.

It was using around 29kWh/month before the leak was noticeable, the new one uses 12kWh/month. The new one is slightly larger than the old. The old model was freezer-on-top style, the new one is a less efficient freezer below model.

Hopefully the new one lasts as long as the old!

shtzvhdx• 9 months ago

Since a fridge's compressor runs about 30% of the time, most of the energy savings of the new fridge are because of a new thermostat.

But the new fridge will not last thirty. Heck, he's lucky if it lasts ten. Five if he lives in an area prone to electrical surges.

xxs2• 9 months ago

Five if he lives in an area prone to electrical surges.

Many fridges have DC compressors and decent enough input filtering, that should be no issue. However, the electronics themselves are another matter.

Most fridges nowadays have defrost cycles controlled by the said processors, with the latter being prone to even software issues. Some fans may not need a replacement, while the fans are cheap and ubiquitous reaching them is another story.

ohman876• 9 months ago

The article mentions ice building up in that old fridge, and this reminded me what I was told by a man who was fixing these things- that the condition of rubber seal and fridge not being leveled correctly can also lead to the ice buildup (if thermostat is not broken). He did not explain in deep technical details why, but said that when the fridge door is not sealing fully then the room air enters the fridge and due to different condensation point it causes moisture buildup at the coldest part. I am not sure how factual this was, since after hearing this I adjusted the fridge so the doors were always closing themselves thanks to gravity, and the ice still kept building up. I did not replace the seal though :)

d_sem• 9 months ago

So can we project from the authors data that, under normal operation, both bridges roughly consume the same amount of power?

userbinator5• 9 months ago

Agree with the others here that this is absolutely not a fair comparison. Most likely the door of the old one was not sealing well, hence the continuous running and frost buildup. I have a late 30s Frigidaire that I restored a few years ago which has been taking around 200kWh/y (70W compressor, ~33% duty cycle.)

koolba• 9 months ago

I have a late 30s Frigidaire that I restored a few years ago

Did I read that right with 30s, as in 1930s?

userbinator5• 9 months ago

Not sure of the exact year, but it should be around 1936-1940.

mmooss2• 9 months ago

not a fair comparison. Most likely the door of the old one was not sealing well, hence the continuous running and frost buildup

That's an expected cost of old fridges, so I don't know that it's unfair. A major reason old machines are less efficient is accumulated defects (people too!). If I said comparing a new car's fuel efficiency to my old one was unfair, because my old one has a lot of problems, you might say that's very fair.

chii• 9 months ago

it depends on why and exact purpose of said comparison.

If the comparison is meant to show the drop in efficiency as part of age and usage, then yes.

However, if you wanted to _only_ compare design upgrades, you don't want wear and tear to confound the results.

modo_mario• 9 months ago

If I said comparing a new car's fuel efficiency to my old one was unfair, because my old one has a lot of problems, you might say that's very fair.

If it's a simple as not driving the old one with punctured tires and replacing those first to get a dramatically different comparison then no i'd say it's unfair.

Replacing a broken thermostat or fixing a rubber seal isn't a huge thing. Why else make the comparison? Who cares about this broken one?

rpcope16• 9 months ago

Honestly given how many compromises there are in refrigerants sold now, it wouldn't surprise me with new seals and a good compressor motor if the old stuff did better.

Cthulhu_2• 9 months ago

For sure, the base tech in a freezer hasn't changed in the past 50 years. Different refrigerant maybe (CFCs are bad mkay), maybe different insulation material, but the rest has just been adding smart features and buttons that really are secondary to the main function of a freezer.

nottorp• 9 months ago

It's also possible that the thermostat inside was broken. For a 30 year old appliance it was probably impossible to find a replacement, but if you can replace it and it doesn't cost as much as a new fridge, that would fix it.

Cthulhu_2• 9 months ago

I'm 99% confident that freezer thermostats are cheap and generic components that haven't changed much in the past decades, however, finding and installing it is a whole other matter.

torginus• 9 months ago

I am not even sure there's anything wrong with the old fridge.

Ice buildup on the cooling element is normal in old fridges - you need to melt them down occasionally - we used to do this once a year, as ice insulates the element from the inside of the fridge and prevents it from working properly.

I thought this was common knowledge.

bfkwlfkjf2• 9 months ago

Anybody know how the author collected the energy consumption data?

ranger207• 9 months ago

From a link in TFA: https://ounapuu.ee/posts/2024/05/02/smartplugs/

bfkwlfkjf2• 9 months ago

Thank you for the link. May I ask what TFA means though?

codedokode3• 9 months ago

Electricity is so cheap (8-9 cents per kWh), it doesn't even make sense to invest in saving it. I would any day choose a cheaper product over 20% more expensive one that uses 10% less power.

russelg• 9 months ago

And if you didn't live in a place where it's cheap?

codedokode3• 9 months ago

Then one need to do the calculations and decide based on that. One should also remember that the product might break so if it repays it cost over many years, there is a chance it breaks long before that.

However, LED light bulbs are worth buying, the cheap ones (less than $3) repay their price in several months even with our electricity pricing.

foofoo122• 9 months ago

Electricity prices varies a LOT depending where in the world you are: https://worldpopulationreview.com/country-rankings/cost-of-e...

codedokode3• 9 months ago

I wonder why it is so expensive (46 cents) in Italy when other EU countries have lower prices. Taxes? Monopoly? Corruption?

And why China has cheap electricity? They don't have much oil.

Could it be that electricity price is based not on real expenses, but simply on "how much they can pay" principle?

Anyway, Western Europe stands out as a dark spot on mostly light-colored map.

insaneirish• 9 months ago

My delivered cost of electricity went up about 50% per kWh in the last few months and is therefore 3x what you mention and likely only going higher.

[AI driven] data center power consumption is real and as of right now, it seems like other consumers are subsidizing it.

calmbonsai• 9 months ago

Well, um, yeah. If you're comparing anything to crap it will be better than...crap.

senectus1• 9 months ago

years ago we were renting a property that came with a fridge.. and our electricity bills where huge. I turned it off and our power bills more than halved. It was enough for us to buy a new fridge and barely notice the powerbills change after that

nakamoto_damacy• 9 months ago

Nobody talking about the refrigerators in Europe. They work differently. The ice forms inside the fridge part not just the freezer part. I don't know why and have not looked into it but it is in every fridge, including brand new ones.

jeroenhd3• 9 months ago

Ice forming inside of the fridge is a result of moisture making its way into the fridge and staying in contact with the cooling elements.

The cause can be a lot of things, from broken drain pipes to damaged door seals. A well-functioning fridge shouldn't have (much) ice buildup unless you live in a hot and humid area.

Some modern fridges (usually the luxury models) also have features to defrost themselves if they detect that there may be frost buildup, but many fridges still have you do it manually.

rpcope16• 9 months ago

One thing that catches my eye here is the use of a smart plug on the refrigerator for current monitoring. I've tried a ton of different ones including the "good" ones like Shelly, and they all seem to use shunt resistors to gauge power draw. It would make me really nervous to use something like that to measure power draw on a big inductive load like a fridge. It's a shame, I've never seen a current clamp in plug form with no on/off switch, so you've basically gotta do some fab work, but that's basically really the only safe way to collect current data for anything that pulls a non-trivial amount of power.

thekoma• 9 months ago

Can you elaborate a bit further on what you’d need to do and why? It’s been a while since my electrical courses.

I’ve been trying to measure home power consumption with these plugs (and the ones from IKEA) but I’ve been getting suspicious readings for inductive loads.

jeroenhd3• 9 months ago

The IKEA plugs have a tidbit in the manual that says a "motor load" is limited to 300W while a resistive load can reach the full 3680W (at 230V, probably less if you're in a lower voltage country).

Should be fine for modern fridges but older fridges may overwhelm the circuitry.

rpcope16• 9 months ago

I wouldn't bother using a smart plug. The other thing that's real dangerous about them that I didn't really elaborate on is the relay. There's a reason on something like a pump, fridge, AC unit, etc. you'd see a real contactor instead of a relay, and it's because relays are inappropriate and have dangerous failure modes for big loads like that and are typically way too small.

In most real non-resi situations, you'd probably isolate the hot leg and put a good CT (current clamp) on it and read that. The great thing about that is you haven't added anything in the power path for the device, like a shunt which is what most smart plugs use. Current clamps are good for a lot more current (though I guess a proper shunt could do it too). The easiest way to do this in your setting is to find a good UL-listed electrical box with cable glands, a short piece of DIN rail, a male and female plug pigtail, some proper THHN wire and wirenets and a Shelly 50A EM Pro, and just graft the EM Pro into the box and wire it up with it's CT. You've now got something signficantly more durable and probably safer (and correctly specced for the load). I've done other things like using an HV Labjack and some good CTs or other one or few off designs. There's lots of stuff in the commercial/industrial space that does this well but it tends to be $$$. Again, for the sake of my own family, I wouldn't use non-UL stuff (most plugs and things that go in gangboxes that are "smart" aren't UL listed, and MAYBE are ETL) as you who knows how much or how well it's tested.

pjc502• 9 months ago

Isn't this just a question of correctly sizing the shunt?

Hall effect would also be possible, but more expensive.

rpcope16• 9 months ago

Yeah, but you don't get do the sizing, it's done by whatever the engineer that designed the plug wanted. I don't know why you'd do hall effect for an AC circuit, a good regular old current clamp should get you as much accuracy as you'd ever want.

ghtbircshotbe• 9 months ago

Just to be pedantic, you could have a current meter where the clamp/hall sensor is internal and not clamped on the power cord.

rpcope16• 9 months ago

That's what I'm say, but I've never ever seen one. I would love to buy one with a current clamp integrated, as it would save me from needing to fab a box and build something, but I don't know of any that exist today.

johnnyApplePRNG• 9 months ago

assuming that it doesn’t break down.

Ha! Good luck with that.

The last time I bought a brand new freezer... it died in under 5 years... can't remember the brand... some asian import to Canada here.

I went out and bought a used kenmore I think it was off of Marketplace... >15 years old and it lasted longer than the brand new one did... at 1/4 the price!

These were both chest freezers and besides it's compressor being slightly louder, I doubt it used much more energy at all. If anything, it was probably insulated better, and used less I would imagine. It was much heavier, at least.

casey2• 9 months ago

If you have to buy 5+ refrigerators in the time the old one you are likely doing more harm to the environment than marginally more electricity consumption

Comparing the power consumption of a 30 year old refrigerator to a new one

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