degree days

The difference between the building’s balance point (the temperature at which the heating or cooling system begins to operate) and the average outside air temperature. Degree days are calculated for heating - heating degree days (HDD), and for cooling - cooling degree days (CDD). Degree days are a measure of the energy needed to cool or heat a building. The Energy application calculates degree days as part of the weather model data it creates when you run the Update Calculations task.