Degree Day Calculator

Formula

To calculate the Degree Days (DD):

\[ DD = \frac{T_{max} + T_{min}}{2} - T_{base} \]

Where:

\(DD\) is the Degree Days
\(T_{max}\) is the Maximum Temperature for the day in °C or °F
\(T_{min}\) is the Minimum Temperature for the day in °C or °F
\(T_{base}\) is the Base Temperature in °C or °F

What is a Degree Day?

A Degree Day is a measurement used in weather forecasting and energy management to quantify the demand for heating or cooling in buildings. It represents the difference between the average outdoor temperature in a 24-hour period and a standard base temperature (usually 65 degrees Fahrenheit or 18 degrees Celsius). If the average temperature is above the base, it’s a Cooling Degree Day, indicating a need for air conditioning. If it’s below the base, it’s a Heating Degree Day, indicating a need for heating. This helps in estimating energy consumption and costs.

Example Calculation

Let's assume the following values:

Maximum Temperature (\(T_{max}\)) = 25°C
Minimum Temperature (\(T_{min}\)) = 15°C
Base Temperature (\(T_{base}\)) = 18°C

Using the formula:

\[ DD = \frac{25 + 15}{2} - 18 = \frac{40}{2} - 18 = 20 - 18 = 2 \]

The Degree Days (DD) is 2°C.