Heating degree day

{
  "id": "MLC-T-ENV-013084",
  "term": "Heating degree day",
  "field": "Environment",
  "term_source": "Heating Degree Day",
  "definitions": [
    "Heating degree days are used to estimate how cold the climate is and how much energy may be needed to keep buildings warm. HDDs are calculated by subtracting the mean daily temperature from a balance temperature, and summing only positive values over an entire year. The balance temperature used can vary, but is usually set at 65°F (18°C), 68°F (20°C), or 70°F (21°F).",
    "The number of degrees per day that the average daily temperature is below 65° Fahrenheit. The daily average temperature is the mean of the maximum and minimum temperatures for a 24 hour period. (See Degree Days)"
  ],
  "abbreviation": "HDD",
  "subject": [
    "Air",
    "Climate change"
  ],
  "references": [
    "Heat Island Effect Glossary",
    "Greenhouse Gas Emissions"
  ],
  "url": "https://mlchart.com/terminology/environment/heating-degree-day/"
}