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In your energy consumption overview, you can also get a comparison of your consumption taking degree days into account. Change the view from Monthly to Compare, and toggle on Degree days normalized, and get the overview.
Degree day explanation
To compare the monthly and annual heating consumption of a building, it is necessary to account for weather conditions. Since outdoor temperature has the greatest impact, temperature measurements are used to normalize the consumption. This is done using the concept of degree days.
A degree day represents the difference between an "indoor" average daily temperature of 17°C and the actual outdoor average daily temperature. The number of degree days for a given day is therefore calculated as the difference between 17°C and the outdoor average daily temperature.
The calculation is based on temperature measurements from the nearest weather station to ensure the most accurate degree day calculation possible.
To normalize energy consumption, normal months are used. These are calculated based on temperature measurements from the nearest weather station over the past 9 years. A normal month thus represents the average monthly degree days over this 9-year period.
A distinction is made between degree day dependent (GAF) and degree day independent (GUF) portions of energy consumption. The idle energy use in the building throughout the year, which is not related to temperature, is referred to as degree day independent (GUF). To calculate GUF, the three summer months—June, July, and August—are used, as it is assumed that energy consumption during this period does not go toward heating the building.
Only the degree day dependent (GAF) consumption is considered when normalizing energy use.
Normalized Consumption = GUF + (GAF * GD_normal / GD)
GUF: Degree day independent consumption
GAF: Degree day dependent consumption
GD: Number of degree days recorded
GD_normal: Number of degree days in a normal month/year