As the world continues to warm, the share of households with residential air conditioning (AC) could grow from 27% to around 41%, depending on climate and socioeconomic scenarios.  This would imply a doubling of residential cooling electricity consumption and 590 to 1,365 million more tons of carbon dioxide equivalent emitted. However, this does not mean that access to AC will be equal for all. A new study led by CMCC researchers investigates future global AC adoption and energy use by 2050, as well as the inequalities that will go with it. 

The issue of cooling in a warming world is already a key concern for policymakers at a global level. During the United Nations Framework Convention on Climate Change (UNFCCC) 28th Conference of the Parties (COP28), sixty-four countries signed the Global Cooling Pledge with the ambition to reduce cooling-related emissions by 68% by 2050, increase access to sustainable cooling by 2030, and increase the global average efficiency of new air conditioners by 50%.

As AC adoption continues to increase as a heat adaptation strategy, so have concerns about its impact on energy consumption, emissions, and inequalities. A comprehensive global picture of the potential inequalities in the future expansion of AC use, and therefore also of the energy poverty implications of increased cooling electricity use, is, therefore, an area that requires scientific investigation.

“Assessing cooling adoption and utilization projections and their inequalities has important policy implications for global, regional, and national energy planning as well as for meeting emission reduction targets,” says CMCC researcher Giacomo Falchetta, lead author of a new study entitled Inequalities in global residential cooling energy use to 2050.

The study estimates that the share of households owning air-conditioning may grow from 27% to anywhere between 33% and 48% by 2050 (depending on climate change and socio-economic development scenarios used), which implies a surge in global residential AC electricity consumption, and, therefore, also in emissions. On top of this broader picture, the study presents granular evidence of current and future cooling trends, providing vital information that can enable the promotion of more equitable planning of cooling solutions that can help people cope with heat through public subsidies, international donations, building and city planning, and passive cooling.

Global gridded projections for residential air-conditioning (AC) ownership and use inequality. Maps and bar charts of AC ownership (% and number of households) (A,B) and (C,D) household AC electricity consumption (GWh/yr. and TWh/yr.) Source: Falchetta et al 2024.

These kinds of measures will be extremely important and CMCC’s new study indicates that although there will be a steep growth in the global uptake and utilization of air-conditioning to cope with heat, on a subnational scale and in the absence of dedicated policies, future growth in AC ownership and use will be distributed in a highly unequal manner across regions and income groups.

“Emerging evidence is pointing at the framing of access to cooling as a systemic, multi-dimensional issue that tightly connects to climate change adaptation justice discussions that have been at the center of global climate conferences,” says Enrica De Cian, co-author of the study, professor at Ca’ Foscari University of Venice and CMCC researcher.

The study draws upon and analyzes a multi-country database of household-level microdata covering more than 500 sub-national administrative units in 25 countries, together representing 62% of the world’s population and accounting for 73% of the global electricity consumption.

The combination of global coverage and high granularity of the study gives a vision of the current and projected inequalities in the distribution of AC and its usage. At the same time it also helps identify critical areas of vulnerability in different regions and population sub-groups in need of action to increase adaptive capacity.

“The granularity of our projections is an important contribution that yields new evidence at the scale that matters for policy implementation,” explains Falchetta. “For instance, we show that in highly exposed regions, such as South Asia and sub-Saharan Africa, by 2050, AC will only be extensively available to people belonging to the highest income groups, whereas the vast majority of poorer households will remain without access.”

The datasets resulting from the study are publicly available and can be used for more informed heat vulnerability and impact assessments, as well as supporting decision makers at the intersection of public health, infrastructure planning, and energy and climate policy.

“Our analysis demonstrates the importance of considering more granular information if cooling and energy poverty and inequalities are to be tackled”, says Falchetta.

More information:

Falchetta, G., De Cian, E., Pavanello, F., & Wing, I. S. (2024) Inequalities in global residential cooling energy use to 2050. Nature Communications, https://www.nature.com/articles/s41467-024-52028-8