How does the Net Refrigeration Effect (NRE) relate to the Coefficient of Performance (COP) of an HVAC system?

The Net Refrigeration Effect (NRE) and Coefficient of Performance (COP) are interconnected metrics that describe the efficiency of an HVAC system. The COP represents the ratio of the NRE to the energy input required to operate the system. A higher COP indicates a more efficient system, which is often achieved by optimizing the NRE through proper system design, operation, and maintenance.