What Are Degree Days, and Why Do They Matter?


degree days

At Penn-Mar Oil Company, customers routinely wonder how we do such an excellent job at estimating need in our automatic delivery program. While we cant give away all of our secrets, we can explain one of the terms that heavily dictates how much heating oil you will need to utilize—degree days.

What Are Degree Days?

When we calculate your heating oil needs, we base it on two separate components, the degree day and the K-factor. We use these two figures to determine when your next delivery should be and how much oil you will need. We never want a single customer to run out of heating oil during a storm or period of cold weather.

We calculate the numerical figure for degree days by examining historical data for the temperature on any particular date in your zip code. Then, we average that data and compare it to the mean temperature of 65 degrees. That difference, between 65 degrees and the average historical temperature, is known as the degree days value. The colder that the weather is outside, the more heating oil you will need.

The other factor that we utilize to determine automatic delivery frequency is the K-factor. The K-factor is formulated based on the capacity of your heating oil tank after subtracting a reserve in case of emergency. We divide the degree days number for days in between your deliveries by the K-factor to determine how much fuel will be utilized.

What Can Degree Days Tell You?

If you are interested in energy conservation and making your heating oil go as far as possible, the degree days figure can be very valuable to you! This website allows you to track your heating oil usage over time and how it has correlated to degree day values. This makes it easy to adjust your usage and ensure you aren’t over-using when the weather is warmer. Conservation is the best way to cut costs on your heating oil.

Enjoy Convenient Automatic Heating Oil Delivery with Penn-Mar Oil Company

Penn-Mar Oil Company is proud to be the preferred heating oil provider of Pennsylvania and Maryland residents since 1936. We offer high-quality kerosene, heating oil and off-road diesel, all backed up by our exceptional customer service and convenient delivery service. To order heating oil, please call us today at (717) 276-9617 or visit us online.