Repo created

docs/DAY_DETAILS.md

@@ -0,0 +1,18 @@
+# Day details
+
+*To be completed*
+
+## Degree day
+
+Degree day is basically the heat or cool need of a building.
+
+This need will vary depending on where you live, on outdoor temperature, on quality of your building, etc.
+
+If the weather source doesn’t have this info available, we will calculate using a generic formula (the one used in EU) that way:
+- If the daily mean outdoor air temperature ((min + max of the day)/2) is between 15 °C and 24 °C, then there is no heating or cooling degree day.
+- If daily mean is < 15 °C, heating degree day = 18 °C - daily mean. For example, if daily mean is 13 °C, heating degree day = 5 °C
+- If daily mean is > 24 °C, cooling degree day = daily mean - 21 °C. For example, if daily mean is 27 °C, cooling degree day = 6 °C
+
+While the calculation is made using °C, this value is expressed in the unit you selected in preference.
+
+More info: https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Heating_and_cooling_degree_days_-_statistics