New Energy Star Fridge Performance

crewzer
crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
in Energy Use & Conservation #1
My wife and I installed a new energy-efficient fridge as a part of kitchen fix-up project. I was hoping to get a full seven days of energy data, but several utility" blips" this afternoon reset the Kill-A-Watt meter and nixed that plan.

So, here are the initial numbers:

Old fridge #1: 1996 era 20 cf side-by-side fridge rated at 825 kWh/yr (to be sold or donated)
Old fridge #2: 1993 era 25 cf side-by-side fridge rated also rated at 825 kWh/yr (off, to be conveyed when we sell the house)

New fridge: 2007 22 cf fridge w/ top freezer, Sears Kenmore Item #: 04664254000, Energy Star rated at 448 kWh/yr

(Note: I have a very large extended family, and we’ve done quite a bit of family entertaining over the years. However, with most of our sons, nephews and nieces now off to college, the food bill has (thankfully) dropped dramatically, and so therefore has our requirement for refrigerated storage.)

As of ~11 AM this morning, the Kill-A-Watt meter indicated the new fridge used 7.11 kWh of electrical energy over the past six days and 17 hours. That’s 1.06 kWh/day, or 387 kWh/yr. That’s obviously better than the product spec, but I suspect that’s in part due to our house's reduced ambient temperature in the winter. Based on the product specs, the one new fridge will use ~73% less energy than the two old ones combined.

My short-term plan is to install a dedicated circuit and power the new fridge from my PV energy system. I’ll configure the inverter for HBX mode to use the grid as back up in case the batteries get too low. Assuming the PV system provides all of the energy required for the new fridge, my grid supplied energy consumption will drop by ~13%.

Cool!
Jim / crewzer
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Comments

  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
    #2
    Re: New Energy Star Fridge Performance

    Did you meter the 1996 or 1993 models while they were in use? How did thay fare?
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
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  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    #3
    Re: New Energy Star Fridge Performance

    Brock,

    I did indeed meter both old fridges... they were so close to spec (~2.2 kWh/day in the spring and fall) that I didn't even bother recording the data.

    HTH,
    Jim / crewzer
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #4
    Re: New Energy Star Fridge Performance

    would you mind revealing the new frig you got as that is close to my 21cft i got back when that i will be running tests on now that i have a kwmeter. i doubt this one will last for many more years so it's good to know what's out there.
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  • System2
    System2 Posts: 6,290 admin
    #5
    Re: New Energy Star Fridge Performance

    :-) Just 1.06 kWh/day, for a fridge with top freezer, of that size? I would say THAT'S GREAT !!
    They've come a long way and I'm sure they can in time do better yet.
    All the best and thanks for sharing.
    Wayne
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  • System2
    System2 Posts: 6,290 admin
    #6
    Re: New Energy Star Fridge Performance

    it's a GREAT idea :)
    hbx mode? auto switchover when low voltage condition? thats nice.
    our fridge was a smaller (19' I THINK) enerGy star, and i forget the usage. i will be measuring and posting :)
    unfortunately at the time i was buying on price for the most part, so i know i could do better now.. but, when i feel like dragging that thing out i want to test, its a pretty recent (2 yrs i think) Fridgidaire
    crewzer wrote:

    My short-term plan is to install a dedicated circuit and power the new fridge from my PV energy system. I’ll configure the inverter for HBX mode to use the grid as back up in case the batteries get too low. Assuming the PV system provides all of the energy required for the new fridge, my grid supplied energy consumption will drop by ~13%.

    Cool!
    Jim / crewzer
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  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    #7
    Re: New Energy Star Fridge Performance
    "would you mind revealing the new frig..."

    Here's the info for the basic white Sears model: Sears item #04664232000, Mfr. model #64232. Mine's a slightly different model number because I purchased the unit in the color "bisque" and with reversible doors (both optional = extra $$).

    We also looked at a 20.6 cf model (basic white = Sears item #04667182000, Mfr. model #67182) rated at 432 kWr/yr, but it was too tall for our space.
    hbx mode? auto switchover when low voltage condition?

    That's it... HBX = "high battery transfer"... See page 16 in Outback's Mate manual. I'm also hoping to run the inverter in "search" mode to reduce its tare loss when the fridge is off.

    HTH,
    Jim / crewzer
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #8
    Re: New Energy Star Fridge Performance

    thanks for the info on it jim. i do see it's in your original post that i had overlooked, but a repeat doesn't hurt with the extra tidbits added.
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  • System2
    System2 Posts: 6,290 admin
    #9
    Re: New Energy Star Fridge Performance

    our 18.3cf energy star frigidaire used only .63 kwh in the lst 24hrs. oh yea .

    its A GS18 model but they dont appear to have that on their website anymore.. hmm

    but a point is made i am sure it uses a LOT more than that in summer. its quite cool in our house right now. (around 60)
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #10
    Re: New Energy Star Fridge Performance

    matt,
    why so low with the temp? i used to do that thinking i'd save lots of money, but it only saved about $8. now that was a good 15 years ago and i only saved about 5-10% on the bill and i deemed it not worthwhile to make myself and everybody else cold for that small savings. i don't like mine going below 68, but no higher than 70, unless it goes below 0 outside or one of us gets sick. now i do use a digital setback thermostat as i do like it slightly cooler when it's bedtime. hmmm, that reminds me i didn't measure my 21cf frig's consumption yet. it's hard to see the kwmeter when the outlet is behind the frig. i have a heavy duty air conditioner extension cord i could use on it though for easy reading. guess i'll do that now and report back to everybody how mine did. i did report about 2 years ago that somebody doing an energy evaluation at my home measured the frig at 140w while running. we shall see.
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  • System2
    System2 Posts: 6,290 admin
    #11
    Re: New Energy Star Fridge Performance
    mattl wrote:
    its quite cool in our house right now. (around 60)
    The rest of us, me included, are totally spoiled! I believe there will come a time when we'll all have to get used to those indoor temps and dress for it.
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  • System2
    System2 Posts: 6,290 admin
    #12
    Re: New Energy Star Fridge Performance

    well, the pellet stove gets clogged up when i put it up higher (in market for a new one) , so it stays on low w/the gas set at 60 for when it cant keep up. actually weve gotten used to it, of course the rm w/the stove is usually 65+ and that feels downright warm, we're totally used to it, actually i feel real warm on 62 (dont get me wrong, thats after i adjust to winter which takes some time of course).

    last month our gas bill was $140. thats with the pellet stove probably carrying about 65% id guess. we have an ANCIENT gas furnace, very inefficeint, dont like to run it. i occasionally crank the pellet stive when its cold.

    weve got about 7 bags of pellets, a week on te low setting , left from 3 tons .


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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #13
    Re: New Energy Star Fridge Performance

    matt,
    you should look into replacing your furnace then. you'd be surprised at what's out there and it won't cost you as much in the cost of gas. i used to have a 210,000btu input boiler and i replaced it with a 160,000btu input boiler and this new one blows away the old one. it's over what i need for the house, but it didn't wince at the temps going below 0 and it could've handled 20 below with ease whereas my old one struggled in the early 90s when it went below 0. i do have more insulation now than i did then.
    if you go after another furnace please get your place evaluated for the new one as the insulation you've put in will change your needs.
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  • System2
    System2 Posts: 6,290 admin
    #14
    Re: New Energy Star Fridge Performance

    yep thats always the consideration
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #15
    Re: New Energy Star Fridge Performance

    my results are in as it was 1.5kwh exactly for a 24hr period on my old 21cft roper frig. this averages 62.5w/hr. i saw, typically while running, around 150w and not 140w as was measured by somebody else. this isn't great, but not bad for an older nonenergy star frig. though it's cold outside the ambient temp inside is between 69 and 70 degrees. anybody else have measured results for their frigs?
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  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    #16
    Re: New Energy Star Fridge Performance

    Update for week #2, slightly higher temp setting (35 F near the bottom vs ~32 F last week):

    6.98 kWh / 170 hours = 6.98 kWh /7.083 days = 0.99 kWh/day.

    8-)
    Jim / crewzer
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  • System2
    System2 Posts: 6,290 admin
    #17
    Re: New Energy Star Fridge Performance

    i wonder has anyone here experimented with wrapping a regular fridge in insulation? i can picture easily building what would look like a built in for the fridge that was heavily insulated. i bet that would help! i have a bunch of extra insulation and the space to try that sometime (in my nonexistent spare time).
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #18
    Re: New Energy Star Fridge Performance

    A couple of issues with wrapping a fridge or freezer... Many of the models actually place the condenser in the "metal skin" of the unit (you can feel the sides getting warm while the compressor is running and you will find no heat exchanger on the back or bottom of the unit).

    Also, I would worry about collecting frost/water at the interface between the "skin" and the new insulation--leading to defeating of the insulation due to ice/water forming and causing rust/corrosion leading to early life failure--or at least an ugly situation.

    About the only way you might be able to add insulation is to use a "wet" foam that will form a water proof bond with the skin of the appliance and will not wick water/form ice in it.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
    #19
    Re: New Energy Star Fridge Performance

    Ya, I made that mistake when we first got our chest freezer. I did notice it was warm on the front and sides when running so I assumed that was the "radiator" for the cooling system. So I put a 2 inch piece of pink foam on the top. It decreased my usage by like 50w a day, which was cool until I opened the freezer one day and had water all over the place because it had been condensing between the foam and the freezer.

    It does seem rather silly that they use the case as the radiator, but I suppose it is a large area and easier to do.
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
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  • System2
    System2 Posts: 6,290 admin
    #20
    Re: New Energy Star Fridge Performance

    no kidding, good point. my wife would love the idea of me spraying good stuff all over the fridge. let me try to imagine what i might build a form out of.. :?

    id try it if it was just me in the house ;)
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #21
    Re: New Energy Star Fridge Performance

    try using sheet insulation rather than spraying the frig.
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  • System2
    System2 Posts: 6,290 admin
    #22
    Re: New Energy Star Fridge Performance

    i guess you didnt read brocks experience? :roll: :wink::|
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #23
    Re: New Energy Star Fridge Performance

    If there are air gaps, you can never seal the area well enough... When using solid sheet insulation (or even fiberglass bats) the air-pockets will expand and contract with weather and temperature--draw new (moist air) into the gap, and it will condense (because of the cold wall of the fridge/freezer + the added insulation).

    The only thing that may work is a spray insulation with adhesive qualities and closed cell structure. Everything else will collect moisture where you don't want it.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • System2
    System2 Posts: 6,290 admin
    #24
    Re: New Energy Star Fridge Performance

    I've noticed some of the newer fridges now have a small, 8"X8" condenser with a fan driving air through it when the compressor is running. Located in the back, under the fridge, alongside the compressor. This instead of running piping under the outer skin. Extra noise from the fan, but works great - - until the "rad" clogs up with dust and the fan motor no longer runs due to dust buildup in it's bearings, but not to worry, it's under warranty for a year. :lol:
    Wayne
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  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
    #25
    Re: New Energy Star Fridge Performance

    ;)
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
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  • fatheadl
    fatheadl Solar Expert Posts: 31 ✭✭
    #26
    Re: New Energy Star Fridge Performance

    Hi crewzer,
    My short-term plan is to install a dedicated circuit and power the new fridge from my PV energy system. I’ll configure the inverter for HBX mode to use the grid as back up in case the batteries get too low. Assuming the PV system provides all of the energy required for the new fridge, my grid supplied energy consumption will drop by ~13%.

    How is this working out so far?

    fatheadl
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  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    #27
    Re: New Energy Star Fridge Performance

    Turns out to be a royal PIA to run a dedicated circuit from the power panel to the kitchen in my split-level house. I'm running the AV system at the present, and will look into adding the front-loader HE wash machine and/or the attic gable vent instead.

    Thanks for asking!
    Jim / crewzer
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  • autoxsteve
    autoxsteve Solar Expert Posts: 114 ✭✭✭✭
    #28
    Re: New Energy Star Fridge Performance

    I just received the other day my kill-a-watt meter and immediately plugged it in series with our Fridge. We have a 23 cu ft GE model that is about 4 years old.based upon my electric bill, it's using a LOT less electricity than you guys are posting.... More to come.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #29
    Re: New Energy Star Fridge Performance

    You should be running about 1-1.5 kWhrs per day for the fridge? If it has extra features and/or you use a lot of ice, the power requirements will rise.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #30
    Re: New Energy Star Fridge Performance
    autoxsteve wrote:
    I just received the other day my kill-a-watt meter and immediately plugged it in series with our Fridge. We have a 23 cu ft GE model that is about 4 years old.based upon my electric bill, it's using a LOT less electricity than you guys are posting.... More to come.

    so leave your killawatt meter on it for 24hrs and read to us the accumulated power it used.
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  • System2
    System2 Posts: 6,290 admin
    #31
    Re: New Energy Star Fridge Performance
    autoxsteve wrote:
    We have a 23 cu ft GE model that is about 4 years old. based upon my electric bill, it's using a LOT less electricity than you guys are posting.... More to come.

    "based upon my electric bill" ?? :? What happened to the KILL A WATT unit ?

    Is the fridge turned on ? :evil:

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