What unit is commonly used to measure the energy efficiency of refrigeration systems?

The Coefficient of Performance (COP) is widely recognized as a key metric in assessing the energy efficiency of refrigeration systems. It represents the ratio of useful heating or cooling provided to the energy consumed by the system. A higher COP indicates a more efficient system, meaning that it delivers more cooling or heating output for a given amount of energy input. This measure is particularly valuable in the context of refrigeration as it allows for the direct comparison of the efficiency of different systems, making it easier to determine which units are more cost-effective to operate over time.

In contrast, revolutions per minute (RPM) measures the speed at which a component, typically a motor or compressor, operates, rather than the overall energy efficiency of the system. British Thermal Units (BTU) quantify the amount of heat energy required to raise the temperature of a pound of water by one degree Fahrenheit but do not directly reflect the efficiency of energy usage. Wattage indicates the rate of energy consumption, but it doesn't account for the useful output generated by a refrigeration system, making it less relevant to efficiency comparisons. Thus, the COP stands out as the most precise unit for evaluating refrigeration energy efficiency.