Increase Your Refrigerator's Efficiency in 10 Minutes for About $2

87,691

123

72

Posted in HomeGreen

Introduction: Increase Your Refrigerator's Efficiency in 10 Minutes for About $2

About: I am an ordinary guy. Except that I live in an RV, drive a 250cc motorcycle, have a truck that runs on bio-diesel, am vegetarian, and have had almost 30 jobs in 10 years, including armored truck driver, bicy...

When I was a little kid, supermarkets often had these hanging plastic sheets with slits cut in them over the upright refrigerated produce and dairy sections to keep the cool air in while allowing people to easily reach through and grab the groceries.

It was so easy that no one thought twice about it, but for some reason they all disappeared.

One day I opened my refrigerator, felt all the cool air coming out, heard the compressor kick on instantly, and I still wasn't sure what I wanted, so I stood there like an idiot, trying to decide while being distracted by my money (in the form of electrically generated coldness) spilling all over the floor for no particularly good reason.

So I decided to do something about it.

[UPDATE:
In response to all the comments - com'on guys!  Don't you read the other comments that other people already posted before you write your own? 
More specifically:

"Most of the heat is stored in the items in the fridge" - this is true, IF the fridge is mostly full.  If it is sometimes fairly empty, it will improve its heat holding ability, as well as require less cycling of the compressor, to put full, sealed, bottles of water inside to take up space.

"The items in the door will be warmer"  - Possibly.  Good question.  I'll put a thermometer in there and find out.  I personally don't keep any dairy in the door (mostly condiments and cool water for drinking) so I hadn't thought of that possibility as a negative.

"Why not use velcro / magnets / spring curtain rod instead of tape, so it's removable" - Not a bad idea, though I'm not at all sure how well it would stay in place.  If I happened to have any of those materials lying around, I might try it, but as I have a huge rarely used roll of packing tape, that's what I used.  I wouldn't take it out when loading the fridge after shopping anyway, as thats when it is most useful.

"This won't make a huge difference in energy use" - Almost none of the energy saving ideas I propose will, alone, make a huge difference.  Cumulatively, though, I have a monthly energy usage of under 60kWh (for a two person, one cat, household - with high speed internet, two computers, 27"TV, DVR, videogame systems, microwave, etc) for a cost of less than $8, compared to the US household average energy use of just under 1000kWh.
60 vs 1000.
I feel that speaks for itself.
For a bunch of other tips that won't save that much by themselves, but add up to $1000s in annual savings all added up, see: https://www.instructables.com/id/Not-your-average-save-energy-advice-use-less-en/ ]

Step 1: Get Some Plastic Sheeting

I work as a hauler, so I knew sooner or later I'd end up with a bit of plastic sheeting for free.  Since you probably aren't a hauler, you could always buy a cheap vinyl shower curtain or a roll of plastic sheeting, which should cost somewhere in the range of $1 to $5.  Mine is translucent, just because that's what I happened to get, but it would be easier to find what you are looking for if you get totally clear plastic.

[UPDATE: having used this for a little while now, I would say definitely use totally clear plastic.  If it isn't transparent, it sometimes takes a little while to find exactly what you are looking for, and if you have to spend more time searching past it, it defeats the whole purpose.]

Step 2: Measure and Cut

I measured the area inside the door, and then measured an area of plastic the same width, and twice the height. 
Then I folded over the cut plastic (two make two equal layers) and cut strips into it from the bottom straight up to about 6 inches from the top.

You could do only one layer, and it would still be an improvement over nothing, but the second layer fills in the gaps between the slits of the first layer, without making it any harder to reach through.  I was originally planning to use 3 or 4 layers, but with the type of plastic I have, it got to hard to see through, so I just made two.  If I had totally clear plastic, I probably would have went with 3 layers.

The old supermarket ones only used one, but they used much thicker plastic.

Step 3: Tape It in Place

I used wide clear packing tape, which sticks well to both the plastic sheet and the type of plastic used in fridge interiors.

I suspect this is the strongest attachment method using commonly available materials, which won't hurt the fridge.  You don't want to put any holes into the fridge interior by screwing the sheet in place, because moisture will seep in and that wouldn't be any good.

I had to cut a little section at the top to accommodate the thermostat dial.
I originally planned to tape it on both sides, but I did just the front, more easily accessible side first, and it seemed secure enough, so I'll see how that goes.

And that's it!
Now you can open the door, grab something, even browse for a bit, without all of the cool air spilling out all over the floor.

The difference was obvious almost instantly: in the past, opening the door reliably triggered the compressor to kick on, without fail (not surprising, since the door is the entire height and width of the fridge space), even if it was only opened for a few seconds.
Now I can open it and test what its like to get stuff out and put it back (pretty easy), ad then go get my camera and take a couple of pictures, and the compressor stays off.

For lots more ways to save energy with simple inexpensive (or free) tricks, see my energy guide: https://www.instructables.com/id/Not-your-average-save-energy-advice-use-less-en/

Share

    Recommendations

    • Science of Cooking

      Science of Cooking
    • Pocket-Sized Contest

      Pocket-Sized Contest
    • Microcontroller Contest

      Microcontroller Contest
    user

    We have a be nice policy.
    Please be positive and constructive.

    Tips

    Questions

    72 Comments

    Another thing that helps, at least I hope. I cut some 5/8" thick R-panel material to isolate/reflect/insulate the hot compressor from the carcass of the refer.
    Some companies that make front open "high efficiency" refrigerators put the compressor on top. I think this mod should have nothing but positive effects.
    Why I found this article was because I was searching for info on if installing a small 4 watt muffin fan might help blow more heat away from the compressor.

    1 reply

    Hi, did you try insulating compressor? I have installed reflective foil between compressor and freezer and between condenser coils and refrigerator (I have "european" style fridge, since I live in Europe) and power consumption dropped by around 25%.

    And what about the muffin fan? Did it work?

    You probably wouldn't have to cover the entire opening to get results. I'm going to try taping up the bottom 1/2 of the opening; it won't keep the cold in quite as well, but most of the cold air slides down and out, so it should help way more than 1/2.

    I think the newer a+++ would have used this approach if was that much efficient (up to 20%). They rather use vents to ballance the cooling from the freezer to the other compartments, they even use ion air, etc.

    Take a simple theory. Have you stepped into cold winter and instantly see yourself freezing? Probably not. Thats because the heat of the body its great enough to keep you alive for a period...
    The same apply to fridges, the air isnt hard to cool, but the food inside is, according to their mass and everything.

    Now i dont know why those stores use these methods but not all of them have this. Some have simple doors. I imagine is in order not to let the air conditioner mess up each other.

    3 replies
    user

    Dear Mr. CoolfrostM,

    The total mass of heated objects outside of the refrigerator is absorbed by the ambient air until equilibrium is reached. the thermostat sensor senses the air inside the fridge. Not the food. As you open the door, a suction effect takes some of the pressure inside the fridge. Guess what? The air outside tries to fill up this momentary vacumn and raises the air temp inside the fridge.

    I'm building a meat aging cabinet and in my tests, nothing increased the interior temp and relative humidity than an open chiller door. We tend to open fridge doors more often to take out food rather than put in new batches of food.

    I designed and fabricated refrigerated display curtains back in Asia during the 80's and believe me they do work from keeping the store floor from getting too cold courtesy of the food display units.

    Gilo

    Are thests on this and its efficiency improvements? Thanks!

    "The thermostat sensor senses the air inside the fridge."

    Although makes sense that the air inside has an effect on the cycles fridge begins. They might have more then a mere termometre, because not always notices the air got out. Maybe something related to presure?

    The air inside expands and escape the fridge compartment. The improvement would be very little versus the inconvenience and practicability; some air would still excape (as its not watertight) unless you have a fridge with drawers.

    There are fridges with fast chill and vents inside for that purpose... of replacing the air. Im guessing that its to be ideal upon the future for everyone who cold afford one.

    What a great idea, I have trouble with my freezer frosting up too (as it's an older style fridge that requires you to open both the large fridge door and the smaller freezer door to access the freezer). Perhaps something like this would help for the freezer section too?

    2 replies

    If you have that old of a fridge, you need to replace it with an energy-star model - that will go much further than plastic stripson an energy savings. The electricity savings will probably pay for it compared to what you are paying now with that old fridge.

    user

    I would probably buy an energy star fridge and still use the idea.

    It's not just a savings by way of less electricity required to cool the contents, it's also in Food savings. Just returning from 2 weeks of travel, I found the watercress still fully green. No way would they have lasted that long if I was opening the frig on my routine basis.

    My only concern is whether vinyl is a healthy material.. The smell of new vinyl is pretty strong. I would not want vinyl outgassing into my food supply... maybe if it's left to sun and outgass for a while first...

    The instructables it’s simple and valuable. Thanks.
    It’s most valuable for one or two peoples I believe.. If I would do that at my refrigerator I could get scorned by my kids.
    Other proactive action can help too as to clean the back of the refrigerator (Heat-exchanging pipes) periodically, like once or twice per year should suffice.

    I love this idea and here's why: You mention seeing these at grocery stores when you were younger but don't know why they disappeared. 1st. The fact that you actually saw these things in use on a relatively large scale, at commercial type grocers; to me speaks volumes. Think about it; -would those retailers actually have used those type energy saving devices if they didn't show SIGNIFICANT savings benefits that could be SEEN? I would imagine that during the fuel crisis of the 70's power bills soared... 2nd: So why then did they disappear? The answer is simple: Big time grocers study this kind of stuff very closely; and the truth is the overwhelming vast majority of grocery store shoppers (lots of women and elder ladies) much prefer groceries with nice clean lines, and aesthetically picture perfect displays (not the loose plastic flappy things)...But I strongly suspect that the energy savings from this (for an open grocery store shelving system) is quite significant in terms of percentages (like more than 10%; who knows maybe even like 30% or so). I suspect one of the reasons many might make loosely framed comments such as "this won't save that much" is due to the fact that modern fridges aren't really considered to be the energy hogs we often suspect them to be...So 20% savings in operating costs for something that uses less than 5% could be kinda hard to see; but no doubt SIGNIFICANT with regard to the refrigerator's overall energy use.

    1 reply

    I know it's a bit late of a reply, but... I still see these curtains in SOME stores.
    Specifically, there are 2-3 large liqueur stores in the Wisconsin/Illinois area that use them on the refrigerators that contain the cases of beer. Also, seen in use on virtually ALL walk-in refrigerated supply rooms. That includes things like the local Jewel butcher-to-store doors, and even the frozen food supply area of the local no-name grocery(they have the curtain mounted behind a normal door).

    Ignore the haters. Don't even address them. This is a good idea, and that's what this site is for.

    Great idea!!! I'll try this!

    I have seen clear shower curtains at the big discount stores for as low as $2.99, or maybe it was $3.99. Anyways you would just have to fold it sideways instead of lengthways to double it up. Mold resistant too...

    I honestly don't know if I'd take the time to do this, but I think it's a great idea.  One way you could check to see if it is really saving any money is to use a Kill-o-watt meter to measure the watts used be your fridge, with and without the plastic material.

    Here's the product website


    I've used it to measure the wattage used by various appliances to see where our electrical money was going.  I also use it to test Christmas lights to makre sure I haven't strung too many together

    Great idea. Going to start on it soon. Thx

    Great idea! It's good to think about these things, even if they don't end up saving money. I hate to point out the obvious, but buying the smallest refrigerator that fits one's needs is probably the biggest possible money saver. I switched from standard American full size fridges to the fridges about 1/3 the size, standard in most everywhere else in the world. Sometimes it gets to be a bit of a Tetris game, but it stops me from wasting food, by opening too many containers or by buying more stuff than I can use up in time. I have a separate little freezer that is probably not so efficient, but still probably uses a whole lot less energy than most options.

    For efficiency, I find the trick really is in thinking smaller. I don't have any room for water bottles on the door, but if I did, that would make sense. The more full the fridge, the colder it stays. cheers!