Passenger-car air conditioning systems are now a self-evident part of vehicles, but the technology behind them—and especially the refrigerants used—has undergone significant change over the past decades. Initially, development was driven mainly by the demand for comfort and technical reliability; later, however, environmental considerations took on an ever-greater role. The history of refrigerants illustrates this shift in mindset well.
The beginnings: the dominance of Freon and R12
The first car AC systems appeared in the late 1930s, and they used almost exclusively the refrigerant R12, commonly known as Freon. This chlorofluorocarbon-based substance seemed ideal: it was non-toxic, non-flammable, chemically stable, and delivered excellent cooling performance. All of this was especially important for the automotive industry, since safety and operational reliability were top priorities.
The problems only became apparent decades later. Scientific research confirmed that R12 contributes significantly to the depletion of the ozone layer and also has an extremely high global warming potential. These findings led to the Montreal Protocol, adopted in 1987, which globally launched the phase-out of ozone-depleting substances. The automotive industry had to find a new solution.
The past: the spread of R134a
To replace R12, R134a became widespread in the early 1990s. This refrigerant no longer contained chlorine, so it didn’t harm the ozone layer, while its technical properties allowed a comfort level similar to earlier systems. For a long time it was the industry standard, used in hundreds of millions of vehicles worldwide.
Over time, however, it became clear that R134a was not a final solution either. Although it has no ozone-depleting effect, its global warming potential remains high, so it contributes significantly to climate change. As a result, the European Union and other regulators gradually restricted its use, especially in newly manufactured vehicles.
The present: low-GWP HFOs
From the mid-2010s, the automotive industry responded to tightening environmental regulations by introducing a new generation of refrigerant, R1234yf. This substance belongs to the hydrofluoroolefin (HFO) group, and its global warming potential is orders of magnitude lower than its predecessors’. As a result, it meets current European and international regulations, and today it’s the default refrigerant in the vast majority of new passenger cars. Its use, however, has also brought new challenges: because it’s slightly flammable, system design, safety solutions and servicing all require greater care.
The future: natural refrigerants
Longer-term development increasingly focuses on natural refrigerants, of which carbon dioxide (R744) attracts the most attention. CO₂ can be considered virtually climate-neutral, is non-flammable and non-toxic, making it an ideal solution from an environmental standpoint. Because of the extremely high operating pressure, however, these systems are more complex and costly to design, which for now limits their widespread adoption. They’re currently used mainly in premium and electric vehicles, but as the technology develops they may become increasingly competitive.
HC-based alternative refrigerants also play an important role in the rise of environmentally friendly cooling technologies. Alaska Refrigerants was among the first to bring these products to market, so today the brand is widely recognized in the market for environmentally friendly car AC gases. The company’s HC-based solutions are an increasingly popular alternative for those seeking a more efficient, lower-impact refrigerant for their conventional car AC systems.
The evolution of refrigerants used in car AC clearly reflects the automotive industry’s shift in mindset. While in the early decades the main goal was efficient and safe cooling, today minimizing negative environmental impact has come to the fore. Technology has reached the point where vehicle AC systems impose an order of magnitude smaller burden on the environment, while comfort and reliability remain assured. Future developments are expected to reinforce this direction, steering the industry ever more toward sustainable and natural solutions.
