Note 31. How Cooling Efficiency is Expressed
The Energy Efficiency Manual gives you a wide range of efficiency improvements for cooling equipment and systems. This Note explains concisely how efficiency is rated in air conditioning, refrigeration, and industrial cooling.
Unlike most energy-using equipment, a cooling machine moves heat from one place to another, rather than converting heat from a fuel into some other form. Therefore, cooling equipment requires a modified definition of efficiency. Here you will learn the common efficiency ratings, including coefficient of performance (COP), energy efficiency ratio (EER), seasonal energy efficiency ratio (SEER), and kilowatts per ton.
Another unusual feature of cooling equipment efficiency is its extreme sensitivity to evaporator temperature and condensing temperature. You will learn about the standard rating temperatures of the Air Conditioning and Refrigeration Institute (ARI).