Heating and Cooling Degree Days
The heating/cooling degree-days is provided to the customer and printed on the utility bill each month as a guideline only for knowing how much energy your home may be using. Keeping in mind when it is colder/hotter outside the energy consumed is going to be greater. The degree-days are not used in calculating billing, they are provided as helpful information to the customer as a matter of record for the weather conditions in our area.
The heating/cooling degree-days is a calculation created by the National Weather Service and computed daily and printed in the newspapers and reported on most TV weather forecasts, as well as, your utility bill. During the heating and cooling season, the biggest factor affecting the amount of your utility bill is the outside temperature. The MEAN temperature as established by the National Weather Service for our area is 65 degrees. Each degree off of the MEAN (average of the high and low) temperature, during a 24-hour period is counted as one heating/cooling degree-day. For every heating/cooling degree-day more energy is needed to maintain the temperature desired in the home. A day with 30 heating/cooling degree-days requires on average twice as much energy as a day with 15 degree-days in order to maintain the same temperature.
Example calculation for one heating/cooling degree-day
high temperature of 24 hour period 80 degrees
low temperature of 24 hour period 72 degrees
total of high and low temperatures 152
divided by 2 = 76 degrees
subtract MEAN temperature 65 degrees = 11
Heating/Cooling degrees for this one day is 11
Thus 11 degrees will carry forward to the next day and build for an entire month’s billing cycle to arrive at a total monthly heating/cooling degree days.