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DrClaude
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anorlunda said:
This seems to corroborate my intuition: most of the cold air escapes in the first ~10 seconds.
anorlunda said:
How do you know that?Trainee Engineering said:...
average consumption per day is 1.3 - 1.5 kWh.
as for the issue of difference of leaving the door open for 5 secs vs 30 secs, pretty sure more heat will enter the compartment the longer the door is opened. heat transfer is a time function after all.
so, the longer the door is opened, the more electricity will be consumed to restore the temperature in the compartment to "normal"
I was involved in an argument a while back regarding the term "most".DrClaude said:This seems to corroborate my intuition: most of the cold air escapes in the first ~10 seconds.
marcus said:I certainly agree his wording ("most" of the mass) was ill-advised even if technically correct. "Most" suggests a substantial majority (at least to me and probably to most people) rather than a very slim majority like 50.1% versus 49.9%. Gives the wrong impression --- mostly a matter of nuance.
... We can go with that... it certainly sounds reasonable to me...[COLOR=#black].[/COLOR]DrClaude said:Yes, I meant how much negative heat is lost
I'll bet you meant...DrClaude said:This seems to corroborate my intuition: most of the cold air escapes in the first ~10 seconds.
[COLOR=#black].[/COLOR]... Can we go with that ?... it certainly sounds reasonable to me...[COLOR=#black].[/COLOR]: most of thecoldnegative hot air escapes in the first ~10 seconds.
If you are using a Kill-a-watt meter, or equiv, couldn't you compare overnight kWh to daytime kWh? You'd need to manually log the kWh and time before bed and in the AM, but a week's worth of data should average out the defrost cycles.OmCheeto said:"out of town"?
That doesn't happen very often for me.
But your's is a very good idea.
Though, it may extend this experiment into the "months" range.
But, as an oldster, I'm getting somewhat used to long range experiments.
ps. I will pay someone actual currency, if they can determine which continent jtbell's image is from...
on Tuesday, of course.
OmCheeto said:How do you know that?
@T=180 hours(7.5 days), the energy consumed was 27.69 kwh, which corresponds to an average power of 152 watts.NTL2009 said:If you are using a Kill-a-watt meter, or equiv, couldn't you compare overnight kWh to daytime kWh? You'd need to manually log the kWh and time before bed and in the AM, but a week's worth of data should average out the defrost cycles.
Great devices!Trainee Engineering said:using Kill A Watt...
OmCheeto said:@T=180 hours(7.5 days), the energy consumed was 27.69 kwh, which corresponds to an average power of 152 watts.
Great devices!
I've learned a lot about my refrigerator from the data I've collected over the last week.
One peculiarity during this experiment, was that my refrigerator operated at between 210 & 228 watts.
View attachment 112711
It wasn't until I accidentally triggered it to turn on, and start recording data every minute, that I found out why.
View attachment 112712
For some reason, instantaneous power consumption goes down with time, after the compressor has started running.
And I think I may have captured the defrost cycle:
View attachment 112714
"watts rough" is the the wattage between readings
"watts smooth" is the wattage from time = 14 hours
Entertaining numbers:
On or about t=20 hours, I went out for lunch, in an attempt not to booger my "DON'T OPEN THE REFRIGERATOR DOOR!" experiment, and spent $7.35 for lunch.
From my extrapolation of data so far, it costs me $13.55 to run my refrigerator for a month.
Conclusion: Eating out, even at Taco Bell, is kind of expensive.
Try this.http://www.explainthatstuff.com/electrochromic-windows.htmlrumborak said:I would argue that transparency is actually not desirable for kitchen fridges, from a user's perspective.
This can be calculated with the the data from the first line of mine that you quoted;" ...which corresponds to an average power of 152 watts"Trainee Engineering said:hmm, $13.55, may I have the kWh? because price per kWh from one country to another is different, but kWh remains constant anywhere. a bit curious about the energy consumption when door not opened.
So your refrigerator uses less than half what mine does.Trainee Engineering said:average consumption per day is 1.3 - 1.5 kWh.
Cost: $5,600rbelli1 said:
OmCheeto said:Cost: $5,600
OmCheeto said:For some reason, instantaneous power consumption goes down with time, after the compressor has started running.