Balancing Lifesaving Cooling with Climate Change Concerns

POLICY WIRE — City, Country — Air conditioning is credited with saving over 5,000 lives annually in the United States, yet it contributes to global warming and strains the electrical grid, according to scientists.

As global temperatures rise, heat waves are becoming more frequent, affecting nearly every continent. United Nations officials estimate that approximately half a million people die yearly from heat-related causes. Consequently, the demand for air conditioning is surging.

A recent study published in Nature Health revealed that air conditioning saved nearly 58,000 lives in the U.S. between 2010 and 2020. Globally, the use of air conditioning is expected to triple, increasing electricity demand significantly, as reported by the International Energy Agency and the United Nations Environment Programme.

However, the reliance on fossil fuels for electricity generation means that air conditioning contributes to increased carbon emissions. The U.N. projects that emissions from air conditioning will rise from 4.5 billion to 7.2 billion tons over the next 25 years, nearly matching the current carbon pollution levels of the United States and Europe combined.

Kai Chen, an epidemiology professor at the Yale School of Public Health and the senior author of the study, noted, Air conditioning is effective, but from a climate change perspective, it is not ideal. It leads to higher carbon emissions and accelerates climate warming.

Due to the global energy crisis exacerbated by the war in Iran, several countries have implemented restrictions on air conditioning use. These include Bangladesh, Cambodia, Jordan, Malaysia, the Philippines, the Seychelles, Singapore, and Sri Lanka, which have set limits on cooling temperatures in offices or mandated weekly shutdowns.

Experts from 75 countries and 250 cities are working to find a balance between providing adequate cooling to reduce heat-related deaths and minimizing the impact on climate change. The Global Cooling Pledge is set to meet in September in Singapore to discuss these challenges.

The concept of “cooling degree days” is used to measure the energy required to cool buildings during hot weather. In the U.S., the number of cooling degree days has increased by 28% since 1990, with 2024 setting a record. Europe has seen a doubling of cooling degree days since 1990, with air conditioning use rising by 44%. Usage has tripled in India and more than doubled in Southeast Asia.

Chen’s study analyzed 30 million U.S. death records over 11 years, concluding that air conditioning saved an average of 5,267 lives annually. However, the study also highlighted the issue of overuse, particularly in offices where temperatures are often set lower than necessary.

The study suggested that using air conditioning beyond what is necessary does not save more lives but does worsen climate change. It also pointed out that air conditioning contributes to the urban heat island effect and increases air pollution.

Access to air conditioning is also a matter of equity, as many vulnerable populations cannot afford it. Lily Riahi, head of the cooling buildings and energy unit at UNEP, noted that during this year’s heat waves, many families had to choose between buying medicine and running their air conditioners.

Riahi emphasized the need for “smarter and more equitable cooling” solutions, citing Singapore as an example of effective strategies. Singapore has implemented comprehensive cooling measures, including urban greenery and efficient cooling systems, which have saved an estimated $35 million in energy costs annually and reduced temperatures by up to 14 degrees in some areas.

Despite these efforts, there are times when even green solutions are insufficient, and air conditioning becomes necessary. Chen suggested that fans and low-level air conditioning can be effective until conditions become too hot and humid.

Reporting by Policy-Wire (PW)