The need to heat a given building has decreased over time: the heating degree days value decreased by 11% between 1979 (3 510 degree days) and 2021 (3 126) in the EU. In other words, only 89% of the heating needs were required in 2021 compared with 1979.
In contrast, the cooling degree days value was almost three times higher in 2021 (100 degree days) than in 1979 (37), indicating that the need for cooling (air conditioning) in a given building has increased over the last decades. Heating degree days and cooling degree days are weather-based technical indexes designed to describe the energy requirements of buildings in terms of heating or cooling.
Heating degree days considerably vary across the EU member states. Between 1979 and 2021, Finland recorded the highest average annual heating degree days value (5 665), in contrast to the lowest value observed in Malta (534). This means that for a given building, the need for heating was ten times higher in Finland than in Malta between 1979 and 2021.
Finland was closely followed by Sweden (5 325), ahead of Estonia (4 343) and Latvia (4 160). The member states with the lowest values were Malta (534), followed by Cyprus (780) and Portugal (1 239).
Among EU regions (NUTS 3), Norrbottens län region in Sweden had the highest average annual heating degree days value (6 658) between 1979 and 2021, while the lowest value was observed in Fuerteventura in Spain (18).
Over the same period, the highest average cooling degree days were observed in Cyprus (577) and Malta (574), followed by Greece (272). The member states with the lowest values for this index were Ireland (0.03), Sweden (0.37), Denmark (0.91) and Finland (1.36). This means that for a given building, the need for cooling (or air conditioning) in these four EU member states was negligible between 1979 and 2021.
At regional level, Gozo and Comino / Ghawdex u Kemmuna region in Malta recorded the highest cooling degree days value (589) in 2021, while 0 cooling degree days were observed in 52 EU regions.
For more information on the topic and statistics you can view the following sources:
- Statistics Explained article on heating and cooling degree days
- Dedicated section on energy statistics
- Database of energy statistics
The use of indicators or indexes such as heating degree days (HDD) and cooling degree (CDD) days can contribute to the correct interpretation of energy consumption for cooling and heating of buildings. HDD and CDD are weather-based technical indexes designed to describe the energy requirements of buildings in terms of heating (HDD) or cooling (CDD).
This article aims to present the variations of HDD and CDD since the beginning of the time series in 1979. You can read more about these indices in the methodological file.
The Joint Research Centre kindly provides each year the data necessary to produce this information.
Article Source: Eurostat