What are Heating Degree Days (HDD)?
“Heating Degree Days,” or HDD for short, are a measurement used to quantify how cold it is outside on a given day. HDD are used within the energy industry to estimate how hard a furnace needs to work to keep your home or business warm. The colder it is outside, the higher the number of HDD. As temperatures drop and HDD increase, more energy is needed to compensate and maintain a comfortable temperature inside buildings.