Heating and Cooling Degree Days

What are heating degree-days and cooling degree-days?

Heating and cooling degree-days are indicators of how much energy a typical household will use for space heating or cooling. Studies have determined that for an average outdoor temperature of 65 degrees Fahrenheit or less, most buildings require internal heating to maintain a 70-degree indoor temperature. Similarly, for an average outdoor temperature of 65-dgrees or more, most buildings require air conditioning to maintain a 70-degree indoor temperature. The more heating degree-days you have, the more your home heating unit will have to run, which will mean more energy consumption and a higher heating bill. The more cooling degree-days you have, the more your air conditioner will run, which will mean more energy consumption and a higher cooling bill.

How are heating and cooling degree-days computed?

Take the high and low temperature for the day, add them together, and then divide by two, which gives you the average. If this average is 65F or more, then you subtract 65 from that average to get cooling degree-days. If the average temperature is less than 65 degrees, then you subtract that average from 65 to get heating degree-days. {Example: On a day with a high of 80 and a low of 68: 80+68=148. 148/2=74. 74-65=9 cooling degree-days. With a high of 58 degrees and a low of 24: 58+24=82. 82/2=41. 65-41=24 heating degree-days.}

Click the month below to see that month's temperature information:

Apriil 2013
March 2013
February 2013
January 2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001

PLEASE NOTE: The temperature information for each month has been created as an Adobe Acrobat file format. To view this file the free Adobe Acrobat Reader Plug-in must be installed and working properly. You can download the free Acrobat Reader from Adobe's Web Site.