How R-290 Cooling is Transforming the Automotive Sector and Fighting Super Pollutants

By tackling emissions from mobile air-conditioning systems, these initiatives not only help reduce global warming but also improve air quality and reduce heat-related risks. One of the latest advancements emerging from these efforts is the safe and energy efficient use of R-290 (propane) as a refrigerant in all-electric vehicles. 

The adoption of R-290 as a natural refrigerant is particularly noteworthy because it offers a low global warming potential (GWP) and excellent thermodynamic properties for the combined cycles of heating and cooling electric vehicles. These characteristics make it a sustainable choice compared to conventional refrigerants with benefits extending to improved passenger comfort, longer battery life, and greater vehicle driving range—key factors in making electric vehicles more appealing to consumers and operators alike. Applying R-290 in the automotive industry requires engineered solutions for its flammability characteristics and life cycle refrigerant management, both promoted by the CCAC.

Automotive air conditioning systems using high-GWP R-134a refrigerant are a major source of emissions that force climate change, yet adoption of alternatives remains slow in price-sensitive markets. With CCAC funding support approved  in 2014, Tata Motors Ltd, Mahle and Institute for Governance & Sustainable Development set out to create a prototype air-conditioning system that significantly reduced HFC emissions. 

To solve this problem the cross functional project team created the first commercially viable, safe and cost-saving mobile air conditioning system to use R-152a, a slightly flammable refrigerant with low GWP used in a new design called “Secondary-Loop”. “The small charge of a flammable refrigerant is safely contained in components outside the occupied space with hot and cold non-flammable antifreeze, circulated inside the occupied space for comfort and safety,” explained Dr. Stephen O. Andersen, Director of Research at IGSD.
The pilot project, ‘A Greener Auto Air Conditioner to Save the World’, has been successfully developed and validated on a TATA Motors Utility Vehicle, with a dual AC system in 2019. 

“One of the reasons for the extraordinary success of the demonstration is that the small project team from TATA and Mahle was backed up by hundreds of engineers working for each company who were able to solve any problem with specialized skills and machine shop resources”, said Timothy Craig who co-directed the work for Mahle with Sangeet Kapoor as co-director for TATA.   

The team demonstrated a system that not only lowered emissions but also enhanced energy efficiency. It went on to win the prestigious SAE International, 2019 Environment Excellence in Transportation (E2T) award. 

Their efforts were also recently recognized with the SAEINDIA Foundation Award FY23-24, highlighting among others the success of the CCAC Secondary-Loop Air Conditioning Demonstration Project, which played a key role in developing climate-friendly cooling for electric vehicles. This award shows how innovation and collaboration can lead to meaningful advancements in sustainable transportation. 

With this foundation, CCAC is engaging in the next phase that focuses on scaling up these technologies for wider use, including their application in electric mobility. In 2023 the CCAC approved a project implemented by the United Nations Industrial Development Organization (UNIDO) that aims to develop and implement prototype systems for passenger electric vehicles (EVs) and small commercial vehicles that use R-290 in Secondary Loop Mobile Air Conditioning (SL-MAC) systems, in collaboration with Tata Motors. The project aligns with global climate goals and supports the Kigali Amendment to the Montreal Protocol, which aims to phase down high-GWP HFC-based refrigerants. 

Sangeet Kapoor, General Manager and Head of the Climate Control Department in the Engineering Research Centre at Tata Motors Ltd and a key contributor to this effort, has been instrumental in making the project a success. ‘’It is a matter of great pride for TATA Motors engineers to work on alternate, low Global Warming Potential (GWP) refrigerants in the Mobile Air Conditioning (MAC) systems domain. Continuously strengthening development competencies of thermal systems in ICE and Electric Vehicles – in simulation methodologies, component sizing and prototyping (with vendors), integrating the same in full vehicle prototypes, validating cooling and heating performance at extreme climate conditions - are crucial for the success of any OEM, particularly in warmer territories such as India,” said Sangeet Kapoor. “Projects such as these, put to test our engineering skills for developing, safe and energy efficient MAC system architectures for the Indian automotive industry’’.

Speaking on the project,Mr. Sven Patuschka, Chief Technology Officer at Tata Motors Passenger Vehicles Ltd and TATA Motors Electric Mobility, said “Tata Motors has been at the forefront of innovation and is constantly working towards shaping the future of mobility. As a part of our R &D efforts, we are committed to pioneering and inventing solutions to a greener future in the auto industry and this initiative is a step in that direction. We will be the first OEM in India who will be developing and evaluating a mobile air conditioning and a battery cooling system that safely uses R-290 in EV’s. We are delighted to partner with institutions like CCAC and UNIDO to contribute to the United Nations Environment initiative.”
“Building on CCAC’s prior project on the development of a difluoroethane (R152a)-based air-conditioning system for internal combustion engine vehicles, this project explores the safe use of the highly efficient, low-global-warming-potential (GWP) refrigerant R290 in EVs,” said Yunrui Zhou, UNIDO’s Industrial Development Officer and Project Manager.  

The project will address key technical challenges, such as flammability and system optimization. The TATA Motors Ltd engineering team will leverage advanced designs of the secondary loop systems, heat exchangers, and electric compressors to ensure safety, energy efficiency, and environmental sustainability.  By demonstrating the feasibility of R-290 in cooling and heating applications for both passenger and commercial EVs, this initiative could drive a systematic shift in the global Mobile Air Conditioning (MAC) sector, accelerating the transition towards climate-friendly refrigerants.

“The pioneering of Mahle, TATA, IGSD, CCAC, and now UNIDO is part of the reason that Ford Motor Company, on behalf of many other global automobile manufacturers – as petitioned the United States Environmental Protection Agency (US EPA) to list R-290 for all electric vehicles”, said Timothy Craig.
The CCAC’s work over the years—from early webinars to industry recognition —has consistently paved the way for greener solutions in automotive cooling. Each milestone brings the world closer to a future where mobility is both efficient and environmentally responsible.

“The use of R-290 in electric buses represents more than just technical progress; it’s a demonstration of how global partnerships and shared goals can lead to tangible climate and health benefits,” said Martina Otto, Head of the CCAC Secretariat. “This project is living proof of how small-scale funding can unlock large-scale transformation and sets a strong example for how we can transition to cleaner, greener transportation systems.”