Confused about Energy Star ratings
Looking at a refrigerator’s Energy Star Ratings, and getting confused. Let’s take the Whirlpool model WRB322DMB* as an example.
1. Here, Energy Star claims this model is a 22.1 cf refrigerator, use is:
= 584 kwh annually in the US
= 423 kwh annually in Canada. http://pdf.lowes.com/energyguides/883049288505.pdf
How can this be? It runs 24/7/365 in both countries, so the only factors affecting power use would be how often it is opened and the ambient temperature around it. Is this difference due to the average temp in Canada being lower, so when Canadians open their refrigerator it takes less time to recover?
2. Here, the exact same model is rated as a 21.9 cf refrigerator that uses
= 404 kwh annually in both the US and Canada: https://www.whirlpoolinsidepass.com/assets/pdfs/product/EnergyGuide/WRB322DMBM_Energy%20Guide_EN.pdf
3. Here, the Kitchen Aid “clone” of the same model (Kitchen Aid is a Whirlpool Brand), with same features, is rated to use
= 500 kwh annually in the US
= 423 kwh annually in Canada http://pdf.lowes.com/energyguides/883049361062.pdf
How can the differently shaped handles between this and the above result in a 84 kwh decrease (compared to #1) or a 96 kwh increase (compared to #2) in the US, but not affect kwh usage in Canada?
Searching the energystar.gov website for data on model WRB322DMB* results in a data matching item #1 above. What can possibly account for these discrepancies? Can we simply not trust the energy star labels? What is going on here?
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Replies
> Can we simply not trust the energy star labels?
They are far more trust worthy than nothing and at ~$20/year of accuracy, I tend to say "good enough".
Humidity and what you put in/take out matters too. More on the complex issue of rating here:
http://www.energyrating.gov.au/sites/new.energyrating/files/documents/2009-eedal-rf-test-procedure_0.pdf
I think dollars per year is the wrong figure to judge them on. $20 may not seem like a lot, but it's over 20% discrepancy in their reported ratings. When you consider that in a lot of categories the only requirement to being awarded an energy star rating is being 10% more efficient than the regulated minimum, 20% is huge. If 20% or $20 per year isn't worth worrying about, then it would have to follow that Energystar itself isn't worth worrying about.
Without Energystar testing/labeling, we would have 200% variations between similar equipment. That's definitely worth worrying about. And if nobody paid any attention to Energystar, it probably would go away.
Have you confirmed that Canada and the US require manufacturers follow the exact same methodology in order to apply the Energy Star label?
The test used to be different but got synchronized a couple of years ago. My guess is some of the fridges were tested under the older procedure some under the new procedure.
That would make sense. The rating would be based on the test methodology used whenever the particular model in question was submitted for testing. A 5 year old model might have ratings based on the testing standards from 5 years ago, for example. I don't know if the manufacturers would be required to submit older, but still produced, models for updated testing but my guess would be they get grandfathered.
Bill
This is a possible explanation, but still does not explain the above discrepancies.
Items 1 and 2 of my post are for the exact same model, so clearly there are 2 versions of Energy Star ratings for one model.
Item 1 of my post is where the US rates it to use 524 kwh/annually and Canadians rate it to use 423 kwh/annually. This would indicate it is the older, "non synchronized" label, and item 2, where they use the same is the newer label.
However, the label linked in item 1 indicates cost to use is based on $0.12/kwh, and the label linked in item 2 indicates cost to use is based on 2007 national average of $0.1065/kwh. The lower cost/kwh and reference to 2007 indicate the label linked in item 2 may be the older one. This would also be consistent with the label linked in item 1 being the one that appears on the energystar.gov website for this particular model, which is presumably the newer one.
So that leaves us with newer labels with new methodology have conflicting annual usage in the US vs Canada.
Other than difference in kwh usage and unit cost, cost and purported capacity of the same model number (all pointed out upthread) the only other discernible difference between the two labels are the numbers after "P/N". I cannot find anything that indicates what "P/N" stands for. Googling the P/N only returns copies of the energy star label for this refrigerator, and an indication that a dryer control board (incidentally also mfg by Whirlpool) has this part number.
"P/N" would normally stand for "Part Number".
Maybe try contacting the manufacturer and ask about the oddball energy star numbers? The only other thing I can think of is that you have discovered a typo or other error that slipped through on the labels.
The only other things I can think of to explain the difference are all goofy, like "Canadians don't open their refrigerators as much as people in the US, so their fridges don't have to cycle as often", which doesn't really make any sense.
Bill
I think fridge energy consumption ratings are up there with car MPG numbers. It is hard to figure out what they will consume in use. Mine was rated for 410kWh/y but I'm seeing 250. I guess it is better than if it went the other way.
A fair bit of energy use will depend on the actual installation details. You have to check where the heat rejection is done (mine was on the side surface) and leave enough of a gap there and the top for efficient air circulation. The manual only shows minimal clearances and doesn't mention that it effects efficiency.
My theory on the discrepancy is that Canucks aren't as indecisive, and thus don't stand around with the door open long as Yanks do figuring which beer they're in the mood for. :-)
I got curious about this issue again, searched and found my own post - LOL!
However I also found a paper on the testing procedures (link below) that claims US and Canada have used the same "MEPS" procedures for refrigerators and freezers since July 2001 (p 23). Per the Energy Star website the refrigerator in item 1 of the OP was tested 3/28/14, well after the procedures became the same in 2001. So it appears differences in testing procedure do not account for the differences in US and Canadian usage. This remains a mystery.
https://www.energy.gov/sites/prod/files/2013/12/f5/naewg_report.pdf