ABSTRACT
464Challenge of refrigeration is to be, as it has always been, invisible. Nonetheless, growing concern about the environment and the climate change has focused the attention in refrigeration, which is responsible for approximately 15% of the total electrical energy consumption in the world and about 2% of the CO2 equivalent emissions to the atmosphere. International and national agreements have favored a revolution in this sector toward refrigerants and systems more environmentally friendly. In this chapter, the environmental impact and current and future trends of refrigerants and systems are discussed from the point of view of energy efficiency. The attention is focused on new generations of refrigerants, the naturals, and those with low global warming potential values.
