A Crash Course in Degree Days

Degree days are an important metric used in the energy industry. They compare the average outdoor temperatures recorded in specific locations to a standard temperature of 65°F (the temperature at which it is assumed that indoor heating and cooling won’t be necessary). The more extreme the temperatures outside, the higher the number of degree days, and vice versa.

Fuel dealers use sophisticated computer software and degree day data to assess their customers’ fuel usage and schedule timely deliveries. There are Heating Degree Days (HDD) and Cooling Degree Days (CDD). Here’s how they’re calculated:

Heating Degree Days (HDD) measures the number of degrees that day’s average temperature is below 65°F. For example, suppose a high of 50°F and a low of 30°F. The average temperature (40°F) will then be subtracted from the standard temperature (65°F), resulting in 25 heating degree days.

Cooling Degree Days (CDD) measures the number of degrees that day’s average temperature is above 65°F. For example, suppose a high of 90°F and a low of 80°F. The standard temperature (65°F) is then subtracted from the average temperature (85°F), resulting in 20 cooling degree days.

In recent years, heating degree days have declined in the United States, meaning heating needs have decreased overall. Conversely, cooling degree days have increased, meaning cooling needs have increased overall.

No matter what the coming days, weeks, months and years have in store, Fsi Oil and Propane has your back. We’ll keep you warm in the winter and cool in the summer with our expert heating and cooling services. When you enroll in a service plan, you’re protected in all seasons. Contact us today to learn more about how we can bring you peace of mind year-round.