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 Star 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:
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-value 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:
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.
It’s worth delving into the history of the Monitor-Top refrigerator, for two reasons: it was very energy-efficient,…