Cool, but polluting

High-pressure gas refrigerants leaking from the cooling systems that chill supermarket display cases are a major source of environmental pollution, according to engineers at the University of Illinois, USA, who think that they might have a solution at hand. Predrag Hrnjak, a professor of mechanical and industrial engineering and a researcher with the air conditioning and refrigeration centre of the university, has claimed that he has found a novel method of refrigeration that -- he claims -- can significantly reduce such leakage of harmful refrigerants. This new method, according to Hrnjak, is efficient as well as economical.