Energy demand for space cooling has increased more than twice as fast as the overall energy demand in buildings over the last decade. Higher temperatures caused by climate change, coupled with increasing incomes and growing populations, are driving rapid growth in residential air conditioning (AC) ownership. Yet, of the 3.5 billion people who live in hot climates, only about 15% owned AC in 2021, with even lower ownership levels in Sub-Saharan Africa and South Asia. Lack of access to indoor cooling puts much of the global population at high risk for heat stress, adversely affecting thermal comfort, labour productivity, and human health. Between 2002-2004 and 2019-2021, the average annual number of heatrelated deaths among people aged 65 years or older increased by 61%, reaching an estimated 300 000 or more deaths.