How many heating degree-days would there be for a day with a maximum temperature of 30°F and a minimum temperature of 20°F? (Assume a base temperature of 65°F.)
A) 65
B) 45
C) 40
D) 35

Question

Quizplus · Accepted Answer

Heating degree days (HDD) are calculated by taking the average of the day's high and low temperatures, subtracting this from a base temperature (usually 65°F), and then summing this over the period of interest. For this question, the average temperature for the day is (30°F + 20°F) / 2 = 25°F. Subtracting this from the base temperature of 65°F gives 65°F - 25°F = 40 heating degree-days.

How Many Heating Degree-Days Would There Be for a Day