Energy-Saving Window Air Conditioners: What You Should Know

Window air conditioner
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In today's age of recession, saving a nickel here and there is a welcome thing. If you use a window air conditioner, any type of energy savings will be a welcome thing. The U.S. Department of Energy estimates that households spend, on average, about 6 percent of their total energy use on cooling spaces in the home. Thanks to new technology and the innovations incorporated into newer window air conditioners, you'll see savings almost immediately by using them. According to The Department of Energy, switching to a high-efficiency window AC can save you between 20 and 50 percent on energy costs, vs. older non-efficient types.

A variety of methods have been introduced to make window air conditioners more energy-efficient, including high-efficiency compressors and fans, and installation and mounting methods that give a tighter fit and are better insulated. As another measure to increase energy savings, many newer window air conditioners have an energy-saver setting that turns the blower fan on and off automatically during operation.

Old Air Conditioners vs. New

A principle difference between new energy-efficient air conditioners and older models is in how the units control the blower fans.

In older units, the thermostat served to control the operation of the compressor—causing it to kick in and deliver more cooled air whenever the air temperature climbed above the defined room temperature setting and shutting it down as soon as the room temperature reached the desired setting. The blower fan, however, continued to run constantly, circulating room air.

In newer energy-efficient air conditioners, the thermostat operates the compressor in the same way as the older models, but you can also set the AC to turn the blower fan on and off at the same time. Thus, these new units conserve all the electrical energy that was used to power the blower fan constantly in older models. This control setting is optional—you can still set the air conditioner to constantly run the blower fan. But the savings are notable by using all the high-efficiency settings: Cost of operation is about 6 percent less with the energy-saving setting engaged.

Advantages of Energy-Efficient Window Air Conditioners

Although high-efficiency air conditioners cost a little more than non-efficient models, there are many advantages:

  • Improved environmental footprint: Overall home energy use is improved, which decreases your overall carbon footprint to the world at large.
  • Better cooling performance: High-efficiency units cool down rooms faster than older models.
  • Quieter operation: With better insulation and higher quality parts, high-efficiency air conditioners run considerably quieter.
  • Better durability: Thanks to better materials and parts, these air conditioners typically last longer than non-efficient models.
  • Flexible controls with "smart: features: ENERGY STAR® compliant window units must have “smarter” features, such as an energy-saving mode and automatic reminders to service the filters.

Most Efficient Window Air Conditioners

Several different sources offer information on what window air conditioners are the most efficient, and the recommendations don't always agree. However, you generally can't go wrong with an air conditioner from a well-known manufacturer, such as those listed below, which are rated ENERGY STAR-compliant.

One of the most carefully conducted analyses comes from AirConditionerLab, a private online resource that offers independent reviews of various air conditioning units by a variety of criteria, including the noise of operation, durability, and energy efficiency. In a 2018 review of 40 different air conditioners, AirConditionerLab provided a report of energy efficiency based on published energy-efficiency ratios, overall performance, industry reviews, and user feedback. The most energy-efficient models were listed as:

In 2016, Consumer Reports issued a report suggesting three recommended energy-efficient window air conditioners in several categories:

Small units (5,000 to 6,500 BTUs per hour):

Medium units (7,000 to 8,500 BTUs per hour):

Large units (9,800 to 12,500 BTUs per hour):

Be aware that manufacturers change model names frequently, and you may find comparable newer models that have different model names but with specifications that correspond almost exactly to the air conditioners on these lists.