Choosing an Energy-Efficient Refrigerator
Select a small refrigerator with the freezer at the top — one without a through-the-door ice dispenser
Because federal appliance efficiency standards have gotten more stringent, new refrigerators use much less energy than those sold in the 1970s. These days, it’s fairly easy to find a full-size refrigerator that requires only 350 to 500 kWh per year — significantly less than the 1,000 kWh/year energy hogs of yore.
Beginning in 2014, the minimum federal efficiency standard for refrigerators will ratchet up another notch, lowering the annual energy bill for a 20-cubic-foot refrigerator to about 390 kWh. Energy StarLabeling system sponsored by the Environmental Protection Agency and the US Department of Energy for labeling the most energy-efficient products on the market; applies to a wide range of products, from computers and office equipment to refrigerators and air conditioners. models will use even less energy.
To reduce the amount of energy used by the typical American refrigerator, several steps are necessary. Engineers, government regulators, and consumers all have a role to play:
- Engineers need to design more efficient refrigerators; this is done by specifying efficient compressors, thick insulation, and high-performance heat-exchange coils. To varying degrees, appliance designers have been working at this goal for at least 90 years.
- Since history shows that appliance manufacturers are unlikely to build efficient appliances voluntarily — even when efficiency improvements are demonstrably cost-effective — we need stringent federal regulations requiring refrigerators to meet minimum efficiency standards. Fortunately, after years of shameful inaction, the U.S. Department of Energy has finally enacted better standards.
- Consumers need to choose small, simple refrigerators without the bells and whistles that waste energy.
Designing an efficient refrigerator
Designing an efficient refrigerator isn’t rocket science; the principles are fairly simple. You want the smallest possible compressor. You want the compressor to be efficient. You want the heat-exchange coils to be generously sized and located somewhere where smooth air flow is possible. And you want thick insulation with a high R-valueMeasure of resistance to heat flow; the higher the R-value, the lower the heat loss. The inverse of U-factor. per inch.
Engineers have traditionally compromised on many of these features. Since thicker insulation reduces the interior volume of the refrigerator, appliance manufacturers have often skimped on insulation so they could brag about the refrigerator’s volume. Similarly, no one wants to look at heat-exchange coils, so they are usually located at the back of the refrigerator, where air flow may not be ideal.
Engineers know that there are two other factors that can improve refrigerator efficiency:
- You can design a chest-style refrigerator that opens from the top (like a chest-style freezer). This design can save a lot of energy (because the cold air in the fridge doesn't spill out onto the floor every time the door is opened), but consumers don’t like the inconvenience of rummaging around to find what’s on the bottom layer of their refrigerator, and most kitchens can’t accommodate refrigerators that open from the top. (If you’re interested in buying this type of refrigerator, SunDanzer makes extremely efficient models that operate on either 12-volt DC or 24-volt DC.)
- You can locate the compressor on top of the refrigerator instead of underneath, so that the compressor’s waste heat doesn’t warm the bottom of your refrigerator.
Only a few refrigerator designers have paid attention to this last point. (Refrigerators with top-mounted compressors are currently available from Sun Frost.) The most famous refrigerator with a top-mounted compressor was undoubtedly the General Electric Monitor-Top refrigerator sold during the 1920s and 1930s.
The Monitor-Top refrigerator
It's worth delving into the history of the Monitor-Top refrigerator, for two reasons: it was very energy-efficient, and my grandfather played an important role in its history.
The GE Monitor-Top was the Model T Ford of refrigerators. General Electric introduced the Monitor-Top in 1925 and manufactured it continuously for 12 years. (A monitor — an architectural feature of some barns — is a ventilating ridge that projects above a barn roof like a crown. As applied to GE refrigerators, the nickname was undoubtedly influenced by the shape of a famous warship, the USS Monitor.)
Early versions of the Monitor-Top (the DR and CA models) had recurring maintenance problems. These problems were all overcome, however, when GE introduced its improved version of the Monitor-Top, the CK model, in 1933. The CK version of the GE Monitor-Top was famously energy-efficient, reliable, and long-lived.
My grandfather, William L. Holladay, was a mechanical engineer who specialized in refrigeration and air conditioning. Among my grandfather’s many accomplishments: he was appointed president of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAEAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). International organization dedicated to the advancement of heating, ventilation, air conditioning, and refrigeration through research, standards writing, publishing, and continuing education. Membership is open to anyone in the HVAC&R field; the organization has about 50,000 members. ) in 1968. (Another fun fact about my grandfather: two decades before becoming ASHRAE president, he wrote a prescient article on ground-source heat pumps.)
Fresh out of Caltech, my grandfather was hired by General Electric in 1924 as the company’s first sales representative for refrigerators. After working for a year at GE headquarters in Schenectady, New York, he was dispatched to Dallas; evidently company executives decided that Texas was a good place to sell refrigerators. As a GE engineer, William Holladay was directly involved in diagnosing and fixing problems with the early Monitor-Top refrigerators. (My grandfather was later hired away from GE by the George Belsey Company, a distributor of GE refrigerators in Los Angeles, Pasadena, and Glendale.)
One of my grandfather’s proudest possessions was a 1934 Monitor-Top refrigerator which operated continuously for more than 69 years. When he died in 2001 at the age of 98, Grandfather's refrigerator was still running — and it was still running two years layer, when his house was sold in 2003.
My grandfather had strong opinions on refrigerator design, and he loved the Monitor-Top. I remember talking with him about refrigerator compressors. He told me (to the best of my recollection), “It makes sense to put the compressor on top. The compressor is hot, and it shouldn’t be located underneath the cabinet. Moving the compressor under the cabinet was a stupid idea.”
A very early energy-monitoring study
Old Monitor-Tops from the mid-1930s used significantly less electricity than modern refrigerators — a fact that my grandfather was well aware of. William Holladay was one of the first engineers to conduct energy-use research on residential refrigerators. He conducted a 12-month energy monitoring study in 1935-1936 involving 114 Monitor-Top refrigerators in Los Angeles. According to my grandfather, he used “souped-up kWh meters accurate to 0.1 kWh.” The results of my grandfather’s study were published in the 1937 issue of Refrigerating Engineering magazine. According to his measurements, the average energy used by these 114 refrigerators was 20.3 kWh per month (243.6 kWh per year). Few modern-day refrigerators can boast of such a low level of energy use. As my grandfather wrote in 1994, “Present-day refrigerators, with larger freezers, run from 60 to 100 kWh per month.”
Several factors contributed to the low energy requirements of the Monitor-Top refrigerator. One factor was good engineering; the other was the refrigerator’s small size. (The two most common sizes of the Monitor-Top were 5 and 7 cubic feet.) Before we conclude that the small size of 1930s refrigerators makes my grandfather’s energy-monitoring data irrelevant, however, we should consider whether we really need to have a 22-cubic-foot monster in our kitchens. (I’ll return to the issue of refrigerator size shortly.)
Years later, my grandfather wrote “The General Electric Monitor Top Refrigerator,” an article published in the September 1994 issue of the ASHRAE Journal. Among the facts he shared in that article:
- Monitor-Top refrigerators were insulated with corrugated cardboard.
- The refrigerant used in the most successful Monitor-Top (the CK model) was sulfur dioxide.
- The failure rate on the Scotch Yoke compressor used for the CK model of the Monitor-Top was only 0.2% per year.
- The CK evaporator was made of stainless steel.
In that 1994 article, my grandfather wrote, “A proud possession of my family is a CK-2 unit on an X-7 cabinet, now more than 60 years old, still faithfully preserving food and making ice cubes in our second home in the mountains. ... We have replaced the starting relay once and the door gasket several times. … The Monitor-Top ... was the DC-3 airplane of household refrigeration: simple, efficient, and long-lived. We will not see its equal again.”
Problems with the Energy Star program and yellow EnergyGuide labels
If you are shopping for a new energy-efficient refrigerator, you might be tempted to focus on the yellow EnergyGuide labels you see in the appliance showroom, or you might look for an Energy Star label. Beware: neither label is necessarily a faithful indicator of energy use.
The Energy Star program doesn’t award its label to refrigerators based on low energy use; rather, the program divides refrigerators into five categories and awards Energy Star labels to the best-performing refrigerators in each category. The five categories are:
- Top-mount freezer models without through-the-door ice dispensers;
- Side-mount freezer models without through-the-door ice dispensers;
- Bottom-mount freezer models without through-the-door ice dispensers;
- Top-mount freezer models with through-the-door ice dispensers;
- Side-mount freezer models with through-the-door ice dispensers.
The basic problem with this method is that some of these categories could be called energy-hog categories. For example, federal regulations for side-mount freezer models with through-the-door ice dispensers (otherwise known as the energy-hog category) require that a 20-cubic-foot model use no more than 608 kWh/year. A refrigerator in this category can get an Energy Star label if it uses 486 kWh/per year (20% less than the federal maximum).
The depressing fact, however, is that such an Energy Star refrigerator still uses more energy than a non-Energy Star 20-cubic-foot top-mount freezer model without a through-the-door ice dispenser, which could use between 379 kWh/year and 472 kWh/year and still not be eligible for an Energy Star label.
The same problem exists with the yellow EnergyGuide labels seen in appliance showrooms. The yellow sticker compares electricity consumption only with models in the same category — side-by-side refrigerator-freezers are only compared to other side-by-side refrigerator-freezers, and not with models with top-mount freezers.
Energy-use numbers are self-reported
The Energy Star program suffers from another weakness: the federal government doesn’t measure the energy use of refrigerators. All the numbers on the yellow labels are self-reported numbers provided by the manufacturers.
Are these numbers accurate? It’s hard to say. When Consumer Reports did their own testing, they found that at least one refrigerator manufacturer, LG, was providing misleading energy-use data. LG rigged one of their refrigerators (model LRFC25750) to turn off a 100-watt electric resistance heater that kept the freezer gasket pliable and frost-free. A relay turned off the heater under only one condition: when the ambient temperature of the room was at 90°F. Not coincidentally, this happens to be the temperature of the test chamber used during EnergyGuide monitoring tests.
Consumer Reports found other problems as well. In an October 2008 article titled “Energy Star Has Lost Some Luster,” the magazine criticized the Energy Star program for its lax standards, out-of-date test protocols, and rules allowing appliance manufacturers to test their own products with little oversight. The article noted that the EnergyGuide label on the Samsung RF267ABRS refrigerator claims that it uses only 540 kWh per year. However, in Consumer Reports tests, which the magazine described as “tougher than the Department of Energy’s” and more likely to reflect the way refrigerators are typically used, the refrigerator’s actual electricity use was found to be 890 kWh per year, about 65% higher than the usage noted on the label. The article continued, “There’s an even larger difference between company claims and our measurements for the LG LMX25981ST French-door fridge. LG says it uses an Energy Star compliant 547 kWh per year. We found through our tests that real-life energy use would be more than double.”
Fortunately, the Energy Star program responded to the Consumer Reports criticism by tightening its protocols and forcing a settlement with LG.
Should we trust the numbers on the yellow EnergyGuide labels? For the time being, we have to. Even though these self-reported energy-use numbers may not be accurate, these labels are currently the best guide consumers have available when refrigerator shopping.
Remember, though: you should only use the yellow EnergyGuide labels to determine the number of kWh used per year. Ignore the chart that compares the refrigerator to other similar models.
Choosing an efficient refrigerator
What are the key features of an efficient refrigerator-freezer? If you want low energy bills, your refrigerator:
- Should be small. Consider buying a refrigerator that with a capacity of 14 to 18 cubic feet.
- Should be a model with the freezer on top. Side-by-side models are energy hogs.
- Should not have a through-the-door ice dispenser.
- Should have a yellow EnergyGuide label that shows very low annual energy use. (If possible, aim for 350 kWh/year or less.)
If your refrigerator has an “anti-sweat” feature — a heater to limit condensation — turn it off. (This switch is often labeled the “energy saver” switch.)
For more information on refrigerator specifications, check out the following resources:
- An Excel spreadsheet listing refrigerators eligible for an Energy Star label
- An Excel spreadsheet listing refrigerators that meet the qualifications of the Consortium for Energy Efficiency
- A website from TopTen USA listing energy-efficient refrigerators
Refrigerators in Europe
How big a refrigerator do you need? Most Americans are used to living with a refrigerator measuring anywhere from 20 to 26 cubic feet. When Americans visit European homes, however, they are often startled to discover that most Europeans are happy with refrigerators that are only half as big.
It’s hard to find up-to-date data on the average size of European refrigerators. One source, however, described the “average European fridge-freezer” as one with 215 liters [7.6 cu. ft.] of refrigerator space and 60 liters [2.1 cu. ft.] of freezer space — that is, an appliance with a total volume of only 9.7 cubic feet.
Anecdotal reports by Americans who are surprised at the small size of European refrigerators are common. Here are some examples from blogs written by Americans living in Europe:
- “I've lived in Paris for about six months now, which is both long enough to get used to and appreciate a different way of life and also long enough for the novelty of certain differences to have completely worn off. One such difference between my life in Chicago and my life in Paris is my teeny-tiny fridge.”
- “Refrigerators in Europe are similar, if not identical to the ones we all had in college.”
- “Sure, there are exceptions, but in general, fridges [in Paris] are about half the size of an American fridge.”
So, here’s my bold suggestion of the week: the next time you buy a refrigerator, consider buying a small one. I’m an enthusiastic cook who enjoys preparing large home-cooked meals three times a day, and my family of four has lived happily with a 10-cubic-foot Sun Frost refrigerator freezer (an RF-12) for 20 years. It uses only 171 kWh per year.
Another option: you can always visit a local antique store and look for an old GE Monitor-Top. If you’re lucky, you may be able to buy a working model for $150 to $800.
Last week’s blog: “When Do I Need to Perform a Load Calculation?”
- William L. Holladay
- General Electric
Fri, 05/18/2012 - 09:14
Fri, 05/18/2012 - 09:47
Fri, 05/18/2012 - 10:27
Fri, 05/18/2012 - 10:37
Fri, 05/18/2012 - 12:30
Fri, 05/18/2012 - 12:43
Fri, 05/18/2012 - 13:25
Fri, 05/18/2012 - 13:43
Fri, 05/18/2012 - 13:53
Fri, 05/18/2012 - 14:05
Fri, 05/18/2012 - 14:08
Fri, 05/18/2012 - 17:59
Sat, 05/19/2012 - 03:43
Sat, 05/19/2012 - 08:44
Sat, 05/19/2012 - 09:31
Sat, 05/19/2012 - 16:58
Sat, 05/19/2012 - 17:11
Sat, 05/19/2012 - 20:33
Sat, 05/19/2012 - 23:05
Sat, 05/19/2012 - 23:36
Sun, 05/20/2012 - 05:20
Sun, 05/20/2012 - 09:06
Sun, 05/20/2012 - 09:20
Sun, 05/20/2012 - 11:07
Mon, 05/21/2012 - 11:48
Mon, 05/21/2012 - 18:00
Mon, 05/21/2012 - 20:05
Wed, 05/23/2012 - 16:29
Wed, 05/23/2012 - 17:44
Wed, 05/23/2012 - 20:54
Wed, 05/23/2012 - 20:54
Wed, 05/23/2012 - 22:09
Wed, 05/23/2012 - 23:09
Thu, 05/24/2012 - 04:17
Thu, 05/24/2012 - 04:21
Thu, 05/24/2012 - 04:22
Thu, 05/24/2012 - 04:28
Thu, 05/24/2012 - 08:10
Thu, 05/24/2012 - 09:14
Thu, 05/24/2012 - 10:53
Thu, 05/24/2012 - 11:04
Thu, 05/24/2012 - 11:12
Thu, 05/24/2012 - 11:15
Thu, 05/24/2012 - 18:31
Fri, 05/25/2012 - 17:59
Sat, 05/26/2012 - 05:17
Sun, 02/17/2013 - 18:40
Mon, 02/18/2013 - 09:31