Cars are changing to use R1234yf as a refrigerant in their air conditioning systems primarily due to environmental concerns and regulatory requirements. R1234yf is a hydrofluoroolefin (HFO) refrigerant, and its adoption is driven by several factors:

1. Environmental Impact: R1234yf is considered a more environmentally friendly alternative to the previously used R134a refrigerant. R134a is a hydrofluorocarbon (HFC) refrigerant known to have a high global warming potential (GWP), which means it has a significant negative impact on climate change when released into the atmosphere. R1234yf has a much lower GWP, approximately 99.9% lower than R134a, making it a less harmful option for the environment.

2. Regulatory Compliance: Many countries and regions have implemented or are in the process of implementing regulations to reduce the use of high-GWP refrigerants like R134a in automotive air conditioning systems. These regulations aim to mitigate the contribution of these refrigerants to global warming and climate change. R1234yf aligns with these regulations and helps automakers meet compliance requirements.

3. Automaker Responsibility: Car manufacturers are increasingly aware of their role in reducing greenhouse gas emissions and their impact on climate change. By transitioning to R1234yf, automakers demonstrate their commitment to using more environmentally friendly technologies and reducing their carbon footprint.

4. Improved Efficiency: R1234yf also offers some technical benefits. It can provide better cooling performance and energy efficiency in air conditioning systems compared to R134a. This improved efficiency can contribute to reduced fuel consumption in vehicles, which is another advantage from an environmental perspective.

5. Safety Considerations: Although there have been concerns about the flammability of R1234yf, extensive testing and safety measures have been put in place to address these issues. The risk associated with R1234yf is considered low, and it is considered a safe choice for automotive air conditioning systems.

In summary, the transition from R134a to R1234yf in automotive air conditioning systems is primarily driven by environmental concerns, regulatory requirements, and a commitment from the automotive industry to reduce the environmental impact of their vehicles. R1234yf offers a more environmentally friendly alternative with a lower global warming potential, aligning with the broader goals of mitigating climate change.

R1234yf generally costs more than R134a for several reasons:

1. Production Costs: The production process for R1234yf is more complex and requires advanced technologies compared to R134a. This complexity stems from the need to manufacture hydrofluoroolefins (HFOs) like R1234yf, which are designed to have lower global warming potentials (GWPs). Producing HFOs with reduced environmental impact often involves more stringent quality control measures and safety protocols, all of which can increase production costs.

2. Research and Development: Developing and commercializing new refrigerants like R1234yf involves substantial research and development expenses. These costs are often passed on to consumers and contribute to the higher price of the newer refrigerant.

3. Limited Supply: As the automotive industry transitions to using R1234yf, the demand for this refrigerant has increased. However, the supply chain for R1234yf may not be as extensive as that for R134a, which has been used for a longer period. Limited supply can lead to higher prices due to market dynamics.

4. Regulatory Factors: The environmental regulations that promote the use of low-GWP refrigerants like R1234yf can indirectly affect its price. Compliance with these regulations may require investments in new equipment and processes, which can also add to the overall cost.

5. Patents and Licensing: The production and use of certain refrigerants, including R1234yf, may be subject to patents and licensing agreements. Companies that hold patents or licenses for these refrigerants may charge fees or royalties to manufacturers, further adding to the cost.

6. Economies of Scale: R134a has been widely used in automotive air conditioning systems for many years, which has allowed for economies of scale in its production. R1234yf, being a relatively newer refrigerant, may not yet benefit from the same level of scale in production, which can result in higher unit costs.

7. Market Competition: Competition among refrigerant manufacturers and suppliers can also influence pricing. As demand for low-GWP refrigerants increases, suppliers may have some pricing power, especially if alternatives are limited.

It's important to note that while R1234yf may have a higher upfront cost, its environmental benefits, such as significantly lower global warming potential, can make it a more attractive option for automakers and consumers concerned about reducing their carbon footprint and complying with environmental regulations. Over time, as the production of R1234yf becomes more efficient and widespread, its cost may decrease, making it a more cost-competitive option in the long run.