Coolants are used  in everything from refrigerators, air conditioners, fire extinguishers, aerosol sprays, medical devices and even semiconductors. Our real-world case for the week is about these coolants.

Until the early 1990s virtually all domestic refrigerators used ozone-depleting chemicals as refrigerants. When the hole in the earth’s ozone layer was discovered, these chemicals – known as CFCs – were banned. Unfortunately the alternatives that were then adapted – HFCs – while less damaging to the ozone layer, turned out to be harmful in a different way. They are powerful greenhouse gases that contribute massively to climate change.  But in the nineties,  Greenpeace successfully initiated the development of an alternative coolant known as ‘greenfreeze’.  This alternative has now been adopted in many countries and by many companies.

What do you think were the driving forces behind this change?  Ibo van der Poel will explain this in the next web lecture.