The article discusses how natural and mixed refrigerants are being seen as better choices for air conditioning and refrigeration systems, to help protect the environment by avoiding ozone-depleting substances. Instead of harmful chemicals, newer refrigerants like R1234ze(E) are being considered to reduce emissions. However, not all new refrigerants work well in all conditions. Researchers are exploring a variety of these new options to find the best ones for different situations, like using R1234ze(E) in chillers to cut down on CO2 emissions. These efforts aim to make air conditioning and refrigeration more eco-friendly and efficient.