Food Storage/Cooking
For Your Home
 
Refrigerators

Styles of Refrigerators
Size of Refrigerators
Factors that Effect Energy Use
Options Available in New Refrigerators
Environmental Issues/CFC's
Energy Efficiency Standards/Super Energy Efficient Models
Second Refrigerators
Maintenance

Refrigerators typically consume the most energy of any household appliance other than the heating, cooling, and hot water systems, amounting to 14% of electricity use on average. However, the efficiency of refrigerators has increased dramatically over the past 20 years, particularly since the passage of the National Appliance Energy Conservation Act of 1987. A typical auto-defrost refrigerator freezer sold in 1972 consumed about 2000 kWh of electricity per year ($200 using national averages); by 1990 that had dropped to 900kWh and by 1994 to 670kWh ($67), for a drop of 66% over the 22 year period, and 25% over the past few years alone. Thus, if you have an older refrigerator, it is likely that a new refrigerator will pay for itself in the form of energy savings!

RefrigeratorThere is a wide array of refrigerator brands in the U.S., but five manufacturers (representing many more brands) currently account for 99% of the market. Over 8 million refrigerators are sold in the U.S. each year.

Full size refrigerators may cost anywhere from $400 to $3,000 depending upon size, style and features, issues described below. The vast majority of "typical" refrigerators cost between $400 and $1,500. Although energy efficiency is likely to have some impact on cost, other factors will typically have a much larger impact.

Styles of Refrigerators
The vast majority of refrigerators in the U.S. are, in fact, combination refrigerator/freezers. Interestingly, this is still not the case in Europe where over 40% of households have separate refrigerator/freezer units.

By far the most common configuration of refrigerator is the Top Mount model, with the freezer unit on top and a larger refrigeration unit on bottom (this is also called a Top Freezer or Top-Bottom style). This style accounts for about 70% of all units sold. In recent years, the Side-by-Side style has become increasingly popular, and now accounts for about 25% of sales. A Side-by-Side model has the freezer unit on one side and the refrigerator on the other, with both units going from top to bottom. Reasons for the increasing popularity of this style is that you do not have to bend as much to find things in the refrigerator, they generally have a larger freezer compartment, and their smaller doors are less likely to get in the way as they swing open. One problem with this style is that, on average, it consumes about 25% more electricity than a Top Mount model.

A Bottom Mount (or Bottom-Top) model, which accounts for about 3% of sales, has the freezer compartment on the bottom. This solves the problem of bending for the refrigerator, but not for the freezer. Energy consumption is slightly better than that of Top-Bottom units for newer models.

The remaining refrigerator/freezer units have a single outside door, with the freezer unit having a separate internal door. The vast majority of recent single door models are small, countertop models (see next section).

Size of Refrigerators
Refrigerator/freezer units have gotten bigger over the years. Storage capacity is measured in cubic feet, typically of the combined refrigerator and freezer units. The smallest units today are countertop units designed for offices or dormitories that have about 6 cubic feet of storage. The largest home units have about 30 cubic feet. The most common home refrigerators are 18 to 20 cubic feet.

When you select a refrigerator, your family size and lifestyle should dictate the size that is most appropriate. Typically, the larger the family the larger the refrigerator. Since refrigerators operate most efficiently when full, it is not very energy efficient to operate a larger refrigerator than you need. In addition, you need to consider the relative sizes of the refrigerator and freezer compartments. A typical 18 cubic foot refrigerator will have a 12.5 cubic feet refrigerator compartment and a 5.5 cubic foot freezer compartment. If you freeze large amounts of meet or prepare meals infrequently and freeze them, you might want to consider a unit with a larger freezer relative to the refrigerator.

Height and width of refrigerators vary as well; you will need to consider refrigerator placement and size when choosing a refrigerator. Until fairly recently, almost all refrigerators were about 36 inches deep and therefore stood out beyond the standard depth of kitchen counters and cabinets. Refrigerators that are the same depth as these cabinets and can appear "built in" started to become popular in the 1970s.Originally, specialty brands such as Sub Zero popularized this style; currently, most major manufacturers also produce refrigerators of this style. To accomplish the smaller depth, the manufactures have typically placed the heating coils above (or beneath) the unit, rather then behind. This makes the unit taller, which can have an impact on the placement in the kitchen. At the same time, the smaller depth makes it easier to find items in the refrigerator. Moving the heating coils from the back both reduces the amount of dust that collects on the coils (which affects energy efficiency as noted below), and makes them easier to clean.

Factors That Effect Energy Use
Aside from style, there are a variety of factors that have an impact on the energy use of a refrigerator:

  • Size -- In general, the larger the refrigerator the more energy it consumes. Each additional cubic foot of space (above the 14 cubic foot minimum of a "full size" refrigerator) adds 20-30kWh of electricity consumption per year.
  • Defrost mode -- Before the new efficiency standards took effect, auto defrost refrigerators consumed nearly twice as much electricity as manual defrost models; today they still use roughly 30% more electricity.
  • Ice Makers -- Automatic ice makers can increase the energy use of a refrigerator by 10% to 15% due in part to a heater used to release the cubes from the mold. Through-the-door ice dispensers create an area of low insulation in the door that adds to the energy consumption.
  • Moisture control devices -- or "antisweat" heaters, are included on some models to prevent condensation on the outside of the refrigerator; these devices can add 10% to energy use. In most climates this heater can be turned off (if a moisture control switch is included) during all but the most humid periods of the year.
  • Door Openings -- Actually, door openings have less impact than most people would think. Most studies estimate that door openings typically account for less than 10% of the energy consumption of a refrigerator. While less than you might expect, this is still significant.
  • Room Temperature -- Perhaps the greatest impact on energy consumption is room temperature. A 10°F increase in temperature can increase energy consumption by 40%! That’s why it is best to place second refrigerators in basements, garages, or other cool locations.
  • Refrigerator Temperature -- The temperature inside the refrigerator will typically vary the energy consumption by about 20% from the warmest to the coolest setting.

Options Available in New Refrigerators
Aside from style, size and defrost options, refrigerators today have a whole host of convenience options that impact price.

  • Glass shelves, are easier to clean than standard wire shelves.
  • Gallon door bins allow you to store large containers, such as milk cartons, in the door.
  • Water filters are built into some models as part of the ice and water dispensing system.
  • Humidity controlled crispers keep vegetables fresh.
  • Adjustable temperature meat compartments allow you to have separate temperature settings for food that might otherwise go off quickly.
  • Optional door panels, to match the decor of the kitchen, are available with some models, including the "built in" style.

Environmental Issues/CFC’s
Most refrigerators use the chlorofluorocarbon CFC-12 as the refrigerant fluid (and CFC-11 as a blowing agent for the insulating foam), both of which have been identified as ozone-depleting chemicals. Under the Montreal Protocol, 100 countries have agreed to phase out these chemicals. Under U.S. law, U.S. manufacturers were required to begin selling CFC-free refrigerators as of January 1, 1996. Most of them have switched to HCFC(hydrochlorofluorocarbon) or HFC (hydrofluorocarbon). However, while these chemicals are considered less environmentally harmful, HFCF is considered to contribute to both global warming and ozone depletion and will be phased out from 2000 to 2003. These chemicals are being viewed as interim measures until other, potentially less harmful replacements can be cost-effectively introduced. Some European manufacturers have introduced more environmentally friendly units. For example, Vestfrost, a Danish company, has introduced a refrigerator that uses R-134A as the refrigerant. This unit is now available in the U.S. through mail order only.

Energy Efficiency Standards/Super Energy Efficient Models
Federal standards for refrigerator energy efficiency took effect in 1990 and were tightened in 1993 and 1998. The standards recognize the factors that affect energy efficiency and vary by size, style, defrost mode, and ice making system. Some manufacturers already sell products that exceed the standards by 20% or more. It is believed that there is room to cut energy consumption with current technology to 40% of the 1993 standard.

A group of electrical utilities formed a consortium to further energy efficient technology through the "Super Efficient Refrigerator Program" (SERP). They offered $30 million to a company that could deliver a refrigerator that exceeded efficiency standards by at least 25%. The winner of this challenge was Westinghouse, with a 22 cubic foot, side by side, CFC-free refrigerator that, when introduced in 1994, exceeded the standard by 30% and by 1995 had exceeded it by 40%. The product is sold under the Whirlpool, Kitchen Aid, and Sears Kenmore brands, but only in the 24 states served by the 20 participating utilities, most of whom subsidize the refrigerator. Westinghouse found that the unit, which carries a higher price tag than models with similar feature and lower energy efficiency, did not sell well enough in other areas.

Second Refrigerators
Approximately 15% of U.S. households have more than one refrigerator. Typically, this occurs when a household buys a new refrigerator and decides to keep the old one for either more storage or for special occasions. Most often, these extra refrigerators are located in the basement or garage.

Since it is generally older refrigerators that are used in this manner, extra refrigerators tend to be very inefficient. In some cases, it would be more cost-effective to buy a larger new refrigerator for the kitchen and get rid of the second one. In other cases, a household with a 10-year-old refrigerator in the kitchen and a 25-year-old model in the basement could actually save money buying a new kitchen unit and replacing the basement model with the old kitchen unit. In almost all cases of a 25-year-old second refrigerator it would be cost-effective to replace that unit with a new model. Obviously, an even more effective strategy would be to get rid of the extra refrigerator entirely, or plug it in only when necessary.

Maintenance
Maintenance can have a significant impact on the performance of a refrigerator. You should vacuum the coils on a regular basis, certainly several times per year. On most refrigerators this will require moving the unit away from the wall, since the coils are often located in the back. (On built-in units the coils are located on the top or bottom and may require the removal of a grille for access). Not only will dust build up reduce energy efficiency, but over time it can dramatically reduce the cooling capacity of the unit, possibly causing it to malfunction. If you are unable to perform this task on your own you should try to find a way to have it done at least once per year, preferably more frequently.

 

   
 
Copyright Aclara Technologies LLC. All Rights Reserved.