Yes, I did. Richard provided the link several days ago in one of his posts. That is the basis for most of what has been discussed here regarding the accuracy of the tests. Go back in his posts, find it and take a look. It says the tests are done with the doors closed, no food, no ice maker, etc.
Years ago I found it and if I remember it simulated
iled your
I think its the wrong refrence. Yesterday I saw at Energy Star stating doors open below 90 or 91f then tests were done doors closed. The true refrence has it stating family usage as well.
iled your
I emailed you a pdf of what I found.
iled your
Ok I found it, and find it extensive in overall testing. sec 3.3 and
4.1.2.3 refer to doors open. Also note test is up to 90f for a period. And 96 hours. I dont see a scam in the testing.
My experience is that most fridges don't have icemakers, and modern ones with icemakers don't consume power like that unless people use immense amounts of ice.
Amount of electrical energy to pump a given amount of heat energy from indoors to outdoors is about 1/3 of the heat energy. Ideally the ratio is
3.41 divided by EER of the air conditioner. And heat energy output of a fridge is same as electrical energy consumption of the fridge, plus only a tiny bit more for heat coming out for items going in warmer than they are coming out - it's close enough to equal to the electrical energy going into the fridge.Cost to pump the heat from indoors to outdoors is zero when outdoors is cool enough to not use an air conditioner.
- Don Klipstein ( snipped-for-privacy@misty.com)
My utility has fixed charges closer to $5. The total per-KWH portion of my bill is close to 14 cents. My most recent electric bill for my
1-bedroom apartment was $33 - including elctric stove.- Don Klipstein ( snipped-for-privacy@misty.com)
An electric stove costs alot to run just like electric heat, Our fixed charges are zero for electric at 13.6 kwh now, Ng is 9$. 20 a month for tv, if you watch it 8 hrs a day every day a new tv might cost
10-15 for me. Obviously few know where they use energy or how to lower it, thats a shame, no wonder our country wastes the most energy.
Public schooled?
That's true, at least for air conditioning serving a small delta T of indoors to outdoors. Not so efficient when delta T is many times larger, going from 0 deg F freezer to warm outdoors. Think about why heat pumps for home heating aren't used when it is the mirror image of refrigeration, with 0 deg F outside and room temp inside.
Conservation of energy of course applies. But if you consider the multiple heat cycles that exposed water in the freezer goes through (chill/freeze/sublimate/condense/freeze/defrost/evaporate/condense), you'll understand why the electric energy consumed per BTU spoils the
3:1 rule of thumb. And why it's not therefore in the DOE test.You can easily prove this to yourself with a duty cycle meter on your refrigerator/freezer, and measuring while making and storing ice, versus icemaker off and no exposed ice. In my experience you go from running constantly while ice is being made to running quite intermittently when there is no icemaking or exposed ice. A puddle of liquid water in a freezer is like a campfire in there, pushing the temp towards 32 deg F when the freezer wants to shut off at 0 deg F.
Then again...
That's about 0.25x4x10/12^3x62 = 0.36 pounds of ice, ie 1.7 Btu/day worth
0.002 cents per day (61 cents per year :-) at 10 cents/kWh with a COP of 3.Nick
Your experience with ice makers is totally different than mine. I don't notice any difference in running time on mine when it's making ice versus when it's not. It's most certainly NOT running all the time when making ice. Good grief, the amount of water that's frozen over a period of about an hour and a half is very modest, maybe a cup or so. You can do the math, but clearly the heat contained in that small qty of water should not make any decent refrigerator run constantly.
Also, you vastly overestimate the sublimation effect. Sure, ice will SLOWLY sublimate. If I leave the ice maker full, unused and off, after maybe a month, the volume will diminish by 1/3. So, we're talking about what? A quart of extra ice it has to make in a month? Sure it uses some energy, but in the grand scheme of things, I don't see this being a big factor. How about all the foods one puts in the freezer that go in above room temp, like two quarts of soup? Isn't that what the freezer is there for and supposed to do? Yet making some ice is supposed to be a big factor?
You're quoting and responding to someone else's post, not mine.
Noticing or not noticing isn't physics. One has to appreciate thermodynamics and the heat of fusion to understand why ice making is so much more energy intensive than making up heat losses through a well- insulated cabinet or warm air infiltration.
I haven't actually made any specific estimate, over or otherwise, but I suppose you mean to say that sublimation and the other wasteful phase changes inside a refrigerator-freezer are trivial, when if fact they are a major factor as evidenced by the need for frequent defrosting and the pivotal role that plays in efficiency.
The trickiness of all debate over efficiency is that you can call things like sublimation trivial that are indeed small, but then you're comparing them to things that have been optimized down to very near zero, like heat gain through insulation, which is what the DOE test measures, then the efficiency ratings based on near-zero effects are still completely spoiled by the comparatively large sublimation type effects that aren't in the DOE tests.
But heat removal is still heat removal as has been pointed out before -- it's only the source and the amount of heat required to be removed from the water to create an equivalent amount of ice is the same for equal amounts of water at the same initial conditions. So again, it would change the magnitude of the numbers, much less effect on the _relative_ results which is the point of the test.
...
You claimed 1.25 times as much energy to move the heat from the kitchen to the outdoors as is consumed by the fridge in article . You claimed in that article $1 per day for the fridge and $1.25 again per day to move the heat from the kitchen to the outdoors.
What does that have to do with the 3:1 rule-of-thumb which I claimed was for an air conditioner? As in the air conditioner's cost of pumping the fridge's heat out of your kitchen being about 1/3 of the fridge's contribution to the electric bill as opposed to your claim of 1.25 times as much?
Not true that most fridges are busy making ice 24/7, nor that this is an argument that the air conditioner contibutes 1.25 rather than .3 times as much to one's electric bill to dispose of the fridge's heat as the fridge contributes to one's electric bill.
- Don Klipstein ( snipped-for-privacy@misty.com)
And of course You are the idiot paying 30 month for an old frige, Im paying 5-6 for a 19,5, you piss your time away BSn yourself with your fancy bs talk on thermodynamicraps, and you lian , still , to yo wife, you pay, I dont sucker. Since this conv started you wasted 5 bucks, keep talkin, Keep waistin, mr putz.
Excuse me. You made the claim that in your experience refrigerators run constantly when making ice. So, which is it? Your OPINION based on physics calcs you haven't done, or your actual observation. I'll say it again. In my experience, with my own refrigerator, it DOES NOT COME EVEN CLOSE TO RUNNING ALL THE TIME WHILE MAKING ICE.
Hmmm, first we have the physics defense, now you say you haven't even made any actual calculations. So, it's pure speculation.
That the DOE tests don't include ice makers does not equate to ice makers result in the refrigerator running all the time. Or that sublimation of maybe 1/3 of a container of ice during a month is a big deal energy wise. All we have is your pure speculation. You have any references to back any of this up?
Simply an observation that if it cost $1 to pump some quantity of heat from inside the refrigerator to the kitchen, it is going to cost about that much to pump it again from the kitchen to outdoors, plus the additional heat generated by the first pump.
The 3:1 rule applies to one hop, moving heat from one place to another. For an air conditioner you're sinking into the outside world on one thermodynamic path, so it's one hop. A refrigerator has multiple paths, and ultimately sinks into the room air, so the heat from making ice has many hops, and the 3:1 rule does not apply. It can be worse if you're air conditioning, or better if you're heating.
Deduction is not speculation. The whole point of engineering analysis is to predict things you haven't tried by use of mathematical laws instead of trial and error. I assert this cup of coffee will run downhill if I spill it. That's speculation?
Early in this thread I cited the US CFR section that specifies the DOE testing procedure (no doors, no contents, no icemaking). Physics and thermodynamics are textbook subjects.
It's pure speculation when you claim that ice sublimation is a large or dominant factor in how much energy a refrigerator uses. You have NOTHING that shows how much energy this amounts to. It's also pure speculation that making ice in the quantities a typical home would use is a big factor in how much energy a refrigerator uses, because again you have NOTHING to base this on.
I can tell you one thing you're dead wrong on. You claimed that a refrigerator that is making ice runs nearly constantly. I told you that in my experience, that is simply not true. To support that, I did a little test yesterday. I emptied out 1/3 of my ice container and kept an eye on the refrigerator intermittently for the next couple of hours. It did not run anywhere near to constantly. It appeared to run about the same as it does any other time, which is a small fraction of the time. I encourage anyone with doubts to try it.
That specifies the testing procedures used and was certainly good information for everyone. However, it does nothing to support your claim that ice sublimation is such a big factor or that a refrigerator runs constantly when making ice. For all you know, the EPA could have figured out that making ice in an average use situation makes only a 5% or 10%% difference in the amount of energy used and chose for simplicity to just ignore it.
And while physics and thermodynamics are textbook subjects, without even any rudimentary calculations, let alone real world tests, citing them doesn't do anything to support your case.
Now, what should I believe? My own eyes and ears seeing that my refrigerator runs only a small fraction of the time making ice or your obviously biased opinions, without supporting evidence?
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.