The best way to determine whether or not an air conditioner is a high-efficiency model is to look at its SEER rating. A SEER rating describes how efficiently an air conditioner converts the energy it consumes into usable cool air for your home.
In order to qualify for the Energy Star label, an air conditioner must have a SEER rating of at least 14.5. Air conditioners with the Energy Star label are about 15 percent more efficient than conventional models.
But is just qualifying for the Energy Star label enough to categorize a unit as a high efficiency air conditioner? As concerns about energy-consumption grow and air conditioners improve in design and efficiency, many experts suggest that a SEER rating of 16 and above is a better standard for high efficiency units. In addition, air conditioners are available with SEER ratings up into the 20’s.