Significant growth of global energy use in the last years has been driven by enhanced demand across sectors such as buildings, industry and transport: the total energy supply increased 2.5 times between
1971 and 2020, and 39% in the last twenty years. In 2020, global energy use in buildings (defined as the sum of residential, commercial and public services sectors) accounted for almost 40% of the total energy use, including primary use of the energy required to produce the associated electricity and heat, generating over a quarter of human-made carbon dioxide emissions.
Following the recent increase in ownership of cooling equipment, although often still far from reaching saturation, cooling is the fastest increasing energy use in the buildings sector: it doubled its share in residential energy use in IEA countries over the last twenty years.
For these reasons, it is important to characterize and quantify the tendency in the cooling request worldwide and this is supported by the availability of a new series of energy-related indicators, provided by CMCC and IEA: The IEA and CMCC Weather for Energy Tracker is a new free platform showcasing weather-related data useful to understand, analyse and model the energy sector, from generation to use across sectors. Data is available at the grid, country and sub-national levels, with a daily and monthly resolution from 1979 to the latest available month, and including monthly climatologies and anomalies based on ERA5 reanalysis.
In contrast to the existent literature, the factors of population-weighting and humidity are considered, which affect the magnitude and the spatial distribution of these changes. Annual tendencies show a general increase of dry and humid cooling degree days over the different countries, fostering more energy consumption for cooling demand. Since the clustering might have an impact on the definition of the energy storage capacity and on the peak energy production capacity of a country, an additional aim is to provide a first assessment of the temporal clustering of such indices, with a special focus on clusters of intense humid cooling degree days (CDDhum), at the global scale. In general, the last decade exhibits a general strong increase both in the occurrence and the duration of clustes, suggesting a potential increase in the cooling demand as well as a more clustered demand, less sparse in time, inducing persistent stress conditions for people and energy providers. We stress that including humidity is important both for general tendencies and clustering. India, Cambodia, Thailand and Vietnam represent the emerging countries where this effect is stronger.