Heating Degree Days
Heating degree day is a term used when calculating energy consumption. It works like this:
65 degrees Fahrenheit is the benchmark. You subtract the average daily temperature from 65 degrees and the result is that days heating degree days number, or HDD for short. For example, if the average temperature for yesterday was 50 degrees, then 65-50= 15 heating degree days. Add each days heating degree days up for the month and you get the HDD total for the month.
Whats this used for?
Its used to see if some maintenance project saved you on fuel. Its hard to gauge fuel savings because the dollars always change. This method removes the dollars from the equation. Say you used 10,000 cubic feet of gas, and the months HDD total was 100. Then you used (10,000 / 100) = 100 cubic feet of gas per heating degree day. Now maybe after some repairs you used 9000 cubic feet of gas the next month, and the heating degree days were the same, 100 HDD. The result would be 9000/100= 90 cubic feet of gas per heating degree day. Thats a 10% savings on fuel. See, your trying to figure out if your saving more fuel after some repairs. Notice how dollars never entered into the equation. This method will also help you determine if setting back a thermostat will help you save fuel. Heating Degree Days is just a tool to use as a gauge.
Monthly Heating Degree Days Total for Cleveland Ohio
August 2006- zero HDD
September 2006- 104 HDD
October 2006- 454 HDD
November 2006- 594 HDD
December 2006- 818 HDD
January 2007- 1041 HDD
February 2007- 1286 HDD
March 2007- 767 HDD
April 2007- 547 HDD
May 2007- 176 HDD
June 2007- 32 HDD
July 2007- 5 HDD
August 2007- 6 HDD
September 2007- 57 HDD
October 2007- 205 HDD
November 2007- 703 HDD
December 2007- 1001 HDD
January 2008- 1080 HDD
February 2008- 1089 HDD
March 2008- 974 HDD
April 2008- 387 HDD
May 2008- 289 HDD
June 2008- 16 HDD
July 2008- 4 HDD
August 2008- 2 HDD
September 2008- 47 HDD
October 2008- 417 HDD
November 2008- 744 HDD
December 2008- 1055 HDD
January 2009- 1414 HDD
February 2009- 968 HDD
March 2009- 790 HDD
April 2009- 459 HDD
May 2009- 179 HDD
June 2009- 39 HDD
July 2009- 5 HDD
August 2009- 12 HDD
September 2009- 56 HDD
October 2009- 388 HDD
November 2009- 513 HDD
December 2009- 1027 HDD
January 2010- 1167 HDD
February 2010-1019 HDD
March 2010- 697 HDD
April 2010- 302 HDD
May 2010- 115 HDD
June 2010- 9 HDD
July 2010- 7 HDD
August 2010- 1 HDD
September 2010- 181 HDD
October 2010- 330 HDD
November 2010- 647 HDD
December 2010- 1189 HDD
January 2011- 1289 HDD
February 2011- 1003 HDD
March 2011- 881 HDD
April 2011- 447 HDD
May 2011- 172 HDD
June 2011- 18 HDD
July 2011- 0 HDD
August 2011- 0 HDD
September 2011- 76 HDD
October 2011- 343 HDD
November 2011- 506 HDD
December 2011- 845 HDD
January 2012- 1000 HDD
February 2012- 866 HDD
March 2012- 432 HDD
April 2012- 481 HDD
May 2012- 104 HDD
June 2012- 25 HDD
July 2012- 0 HDD
August 2012- 0 HDD
September 2012- 139 HDD
October 2012- 372 HDD
November 2012- 734 HDD
December 2012- 836 HDD
January 2013- 1061 HDD
February 2013- 1033 HDD
March 2013- 960 HDD
April 2013- 476 HDD
May 2013- 155 HDD
June 2013- 39 HDD
July 2013- 3 HDD
August 2013- 4 HDD
September 2013- 87 HDD
October 2013- 317 HDD
November 2013- 738 HDD
December 2013- 1015 HDD
January 2014- 1334 HDD
February 2014- 1183 HDD
March 2014- 1010 HDD
April 2014- 425 HDD
May 2014- 180 HDD
June 2014- 20 HDD
July 2014- 14 HDD
August 2014- 11 HDD
September 2014- 118 HDD
October 2014- 357 HDD
November 2014- 834 HDD
December 2014- 907 HDD
January 2015- 1295 HDD
February 2015- 1414 HDD
March 2015- 955 HDD
April 2015- 450 HDD
May 2015- 138 HDD
June 2015- 30 HDD
July 2015- 3 HDD
August 2015- 11 HDD
September 2015- 36 HDD
October 2015- 307 HDD
November 2015- 501 HDD
December 2015- 647 HDD
January 2016- 1139 HDD
February 2016- 941 HDD
March 2016- 623 HDD
April 2016- 520 HDD
May 2016- 211 HDD
June 2016- 13 HDD
July 2016- 0 HDD
August 2016- 0 HDD
September 2016- 11 HDD
October 2016- 218 HDD
November 2016- 487 HDD
December 2016- 1007 HDD
January 2017- 933 HDD
February 2017- 658 HDD
March 2017- 792 HDD
April 2017- 253 HDD
May 2017- 195 HDD
June 2017- 17 HDD
July 2017- 0 HDD
August 2017- 2 HDD
September 2017- 48 HDD
October 2017- 210 HDD
November 2017- 630 HDD
December 2017- 1117 HDD
January 2018- 1172 HDD
February 2018- 808 HDD
March 2018- 916 HDD