From the lab: A greenhouse gas as a cool, green solution [http://cmsenvis.cmsindia.org/resources/newspaper/details.asp?id=86765]Ironically, carbon dioxide is seen as a very viable alternative refrigerant for a variety of cooling requirements. Carbon dioxide was used as refrigerant in air-conditioners long ago, but was discarded when more efficient, low-pressure fluids like CFCs (chlorofluorocarbons) came along. But CFCs were found to be eroding the ozone layer and these got replaced by HCFCs (hydrochlorofluorocarbons) and HFCs. Now, there is an attempt to go back to carbon dioxide as it is a natural compound