In 1992 Greenpeace brought together scientists who had extensively researched the use of propane and butane as refrigerants, with a leading East German household appliance company, Foron, formely, DKK Scharfenstein which resulted in the birth of the 'Greenfreeze' technology for domestic refrigeration. Greenfreeze refrigerators use hydrocarbons for both the blowing of the insulation foam and the refrigerant and they are entirely free of ozone destroying and global warming chemicals.
When DKK Scharfenstein announced their intention to mass produce "Greenfreeze", Greenpeace successfully campaigned to gather tens of thousands of pre-orders for the yet-to-be-produced new refrigerator from environmentally conscious consumers in Germany. Propane and butane are natural gases available without licenses all over the world at prices (in a purified form) comparable to those of CFCs. The energy efficiency of the propane/butane refrigerators has been proved to be as good as those cooled with CFCs or HFC-134a.
Bosch, Siemens, Liebherr and Miele gave up their resistance to the hydrocarbon technology, and introduced their own line of 'Greenfreeze' models in the spring of 1993. Within a year and a half the Greenfreeze technology has throughout Europe, and to other parts of the world. Many models of 'Greenfreeze' refrigerators are now on sale in Germany, Austria, Denmark, France, Italy, Netherlands, Switzerland, and Britain. All of the major European companies are marketing Greenfreeze-technology based refrigerators.
Some "Greenfreeze" refrigerators with isobutane use up to 38 percent less energy than their identical counterparts with HFC-134a. Bosch-Siemens announced a 50% energy savings with Greenfreeze in their 1993 annual report.
For further information on the Greenfreeze story visit: http://archive.greenpeace.org/ozone/greenfreeze/