Hansberger Refrigeration Blog: Your AC Repair Resource

Degree Days: What They Are, And How They Figure Into Your Energy Calculations

Degree days refers to the number of degrees in one day that the average outdoor temperature is above or below a set reference temperature.  The reference temperature represents the most desirable indoor air temperature for human comfort.  The most commonly used reference temperature in degree day calculations in weather data is 65 degrees.

The difference between the average outdoor air temperature and the desired indoor temperature for any given day equals the number of degrees an air conditioning or heating system must condition the air.  In other words,  if the average temperature for a summer day in Southwest Arizona is 95 degrees, and the reference temperature inside is a cool 65 degrees, then this particular day requires the cooling system to cool the outside air temperature down 30 degrees.  Therefore, the degrees days for this particular day would be 30.

If every day during one week experienced an average temperature of 95, then the degree days for that week would be 210, or 30 multiplied by 7.  In this way, you can calculate the amount of degrees your heating or cooling system will have to work for an entire season or a full year using historical temperature data.

Yuma, for example, has an average of 4,244 cooling degree days and 983 heating degree days per year.  It’s easy see from these numbers that the air conditioner has to work a lot harder than the heater in this particular climate.  Having energy-saving products installed in your home, such as a high-efficiency cooling system, efficient filters and insulation, means your air conditioner doesn’t have to work as hard, and thus uses less energy, to keep that indoor temperature at a comfortable level.

If you would like more information regarding degree days and how they can benefit your cooling or heating needs, please contact Hansberger Refrigeration and Electric Co. today.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems).  For more information about degree days and other HVAC topics, download our free Home Comfort Resource guide.

Hansberger Refrigeration & Electric Co services the Yuma area in Arizona. Visit our website to see our special offers and get started today!