Cooling Off While Warming Up: The Paradox of Air Conditioning

Sales of fans and portable air conditioners are on the rise.

Many people are considering more long-term solutions, such as installing permanent air conditioning systems in their homes, and will likely take the plunge in light of the grim forecasts of global warming, which is already well underway…

France nevertheless remains a country with relatively few air-conditioning systems compared to others, starting with the United States, where air conditioning is ubiquitous, even in places where it hardly seems necessary…

So, is air conditioning a solution to global warming, or—on the contrary—a factor that exacerbates the problem, offering only fleeting comfort to those who use it?

The answer is that air conditioning is not a measure to mitigate climate change. On the contrary, when used on a massive scale, it actually exacerbates the problem.

However, its health benefits must be taken into account, particularly for aging or vulnerable populations.

A complex topic…

In August 2017, on a naturally well-ventilated Greek beach, I came across a fascinating article by Benoît Bréville, published in *Le Monde diplomatique*, which described the vicious cycle of air conditioning: a technology designed to protect against heat but which, through its heat emissions and energy consumption, actually contributes to making the heat worse.

I. The Climate Vicious Cycle: Air Conditioning as a Catalyst for Global Warming

Space cooling accounted for more than 2,100 TWh of electricity in 2022, representing approximately 7% of total global consumption, and air conditioning is currently responsible for emitting about one billion metric tons of CO₂ per year. According to the UNEP, these emissions could reach 7.2 billion metric tons of CO₂ equivalent by 2050 if no ambitious regulatory measures are adopted.

The environmental impact of air conditioning is driven by three factors.

First, massive electricity consumption—which is largely generated from fossil fuels in most countries—produces direct greenhouse gas emissions.

Second, fluorinated gases used as refrigerants (hydrofluorocarbons, or HFCs) have a global warming potential (GWP) that can be several thousand times greater than that of CO₂.

Third, air conditioners release the heat extracted from buildings into the outside environment, contributing to the formation of heat islands, particularly in urban areas—a phenomenon that studies estimate causes a local temperature increase of between 0.5 °C and 2 °C.

II. A Legal Framework in the Making

A. From the Montreal Protocol to the Kigali Amendment

The 1987 Montreal Protocol, originally intended to protect the ozone layer, serves as the international legal framework for regulating refrigerants. However, the phase-out of chlorofluorocarbons (CFCs) and then hydrochlorofluorocarbons (HCFCs) led to their replacement with HFCs, which are powerful greenhouse gases. The Kigali Amendment, adopted on October 15, 2016, by 197 countries and which entered into force on January 1, 2019, specifically aims to reduce the production and consumption of HFCs by 80 to 85 percent by 2047.

Its legally binding nature and phased timeline (an 85% reduction by 2036 for developed countries, and by 2047 for others) should make it possible to avoid 70 to 84 billion metric tons of CO₂ eq. and limit global warming to nearly 0.5 °C by the end of the century.

B. The F-Gas III Regulation: Europe’s Ambition

For its part, the European Union has adopted Regulation (EU) 2024/573 on fluorinated greenhouse gases, known as “F-Gas III,” which entered into force on March 11, 2024. This regulation sets forth an ambitious schedule of phased bans: as of January 1, 2025, fluorinated gases with a GWP of 2,500 or higher are prohibited for the maintenance of any refrigeration equipment; in 2027, monoblock air conditioners with a capacity of less than 12 kW that use gases with a GWP greater than 150 will be prohibited; in 2029, R-32 will be banned for split-system units of 12 kW or less. Complete phase-out is targeted for 2032. Quotas for HFCs placed on the market will also be reduced by 75% by 2030.

C. RE2020 and Summer Comfort Under French Law

In France, the RE2020 environmental regulation introduces, for the first time, a summer comfort indicator—degree-hours of discomfort (DH)—which requires builders to design buildings that are naturally resilient to heat. The threshold of 1,250 DH requires a reevaluation of building design, while the calculation is deliberately performed without taking air conditioning into account, in order to encourage passive solutions.

This approach is based on a certain degree of realism: rather than banning air conditioning, lawmakers are seeking to make it structurally unnecessary.

D. Labor Law and Heat Waves (Decree of May 27, 2025)

Decree No. 2025-482 of May 27, 2025, creates a new chapter in the Labor Code devoted to the “prevention of risks associated with intense heat waves.” Based on Météo-France’s four-level “heat wave” alert system, it imposes progressive obligations on employers to adapt working conditions.

The INRS notes that physical labor becomes hazardous at temperatures above 28 °C, and office work becomes problematic at temperatures above 30 °C. This situation provides renewed grounds for employees to exercise their right to refuse to work.

However, the text does not impose any obligation to use air conditioning. It is merely one of several measures (ventilation, adjusting work schedules, insulation, and work organization).

In practice, however, in offices and the service sector, the need to protect employees’ health, combined with the need to maintain economic activity, often leads to a preference for air conditioning, which is the simplest and most effective solution.

Thus, by striking a balance between freedom of means and constraints on outcomes, the law creates a strong indirect incentive to invest in equipment, without ever mandating it.

III. Sociological Divisions: Air Conditioning as an Indicator of Environmental Inequality

A legal analysis would be incomplete without considering the social reality of air conditioning use.

Of the 3.5 billion people living in hot climates, only about 15% have air conditioning. In France, summer energy poverty remains an underestimated reality: 59% of residents in priority neighborhoods under the urban policy (QPV) report suffering from summer heat-related discomfort, compared to 43% in the rest of the country. Access to air conditioning is thus closely tied to income level, reinforcing the classic patterns of environmental inequality.

On a global scale, this disparity is even more pronounced. While more than 90% of U.S. households have access to air conditioning, that rate remains below 10% in India and sub-Saharan Africa—regions that are among the most vulnerable to extreme heat waves.

This situation is fueling the gradual emergence of a debate surrounding a potential “right to freshness,” which, while not yet enshrined in law, is becoming an increasingly central part of legal discourse.

In France, recent heat waves have reignited calls for regulatory measures: mandatory air conditioning in certain facilities serving vulnerable populations (schools, nursing homes), or the creation of “heat-related leave.” These initiatives reflect a growing tension between the need to adapt and the requirement for energy conservation.

This tension is all the more pronounced because the law does not require air conditioning, but rather establishes performance-based obligations regarding health protection and business continuity.

In this context, air conditioning often becomes the default solution in the service sector—not because of any explicit legal requirement, but because it allows for the simultaneous fulfillment of health and economic performance requirements.

But this dynamic reveals a clear paradox: recognizing a right to fresh air without establishing sustainable conditions for exercising that right amounts to reinforcing the climate-related vicious cycle already described.

The legal challenge, then, lies less in establishing a new right than in managing its systemic effects.

Toward Integrated Legal Regulation?

Air conditioning law is currently developing in a fragmented manner at the intersection of several branches of law: primarily environmental law, European Union law, construction law, and labor law.

International instruments such as the Kigali Amendment, European regulations such as the F-Gas III Regulation, and French standards derived from the RE2020 and labor law reflect a growing regulatory framework. However, these measures remain largely sector-specific and insufficiently coordinated.

Air conditioning thus emerges as a hybrid legal issue: a comfort feature, a public health concern, and a key driver of climate change.

Truly integrated regulation would require coordinating equipment energy efficiency, a transition to refrigerants with low GWP, the transformation of buildings and urban planning, and the establishment of a framework for sustainable use.

Only under this condition could the law perhaps address the contradiction posed by air conditioning: protecting people from the heat without contributing to it further.