Tata Motors Limited and MAHLE, one of the world’s 20 largest suppliers to the automotive industry, have signed a joint development agreement for designing and developing a Secondary Loop Mobile Air Conditioning System (SL–MAC), under the aegis of United Nations Environment. MAHLE and Tata Motors, along with the Institute for Governance and Sustainable Development (IGSD), which is coordinating the project, received funding for developing the SL-MAC system from the Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants (CCAC), a global initiative to support fast action and make a difference in the areas of climate, public health, and food and energy security (www.ccacoalition.org). This project envisages use and trial of environment friendly, low global warming potential (GWP) refrigerants HF01234yf (ASHRAE A2L) and HFC-152a (ASHRAE A2). A team comprising of representatives of the California Air Resources Board (CARB), the Mobile Air Conditioning Society Worldwide (MACS), the National Renewable Energy Lab (NREL), MAHLE, Tata Motors, and IGSD reviewed the newly constructed SL-MAC system and the prototype at the MAHLE Behr facility in Lockport, New York, USA, on 7 April 2017. A Tata vehicle based on a new generation platform for utility vehicles, consisting of a more complex architecture with front and rear air conditioning system, has been selected for this joint development program. The SL–MAC system will first be installed in the Tata utility vehicle as a prototype. In the SL-MAC system, the alternative refrigerants first cool a secondary fluid/coolant, which in turn cools the air to comfortable temperatures inside the vehicle cabin. This process allows the safe use of slightly flammable refrigerants that have a low GWP and in turn achieves high cooling capacity, minimizing the losses and achieving an optimized overall thermodynamic efficiency in the process. This is in contrast to the conventional mobile AC system, where the cabin air is directly cooled by the refrigerant HFC-134a, which is ozone safe but has a high GWP.