The "problem" with R12 was that it breaks down in the atmosphere in short order (less than 10 years by some calculations). Most of the replacement refrigerants are basically inert. The estimated lifetime of r134a is 50,000 years. So even tiny leaks over a long period are going to do incredible damage to the climate. This was known from the beginning and is by design (the stable molecule bit).
But even now decades later the political ideology that AC units were the "problem" persists, despite the fact that its well documented that CFC's were used for everything from propellants in consumer products like silly string and hairspray, to large scale industrial uses like popcorn production (again recently in china).
Yet in all this time, we haven't really found a better set of refrigerants.
In the end, we would be better off bringing R12/22/etc back with the stringent controls for licensing/recovery/recycling/leak detection/etc that was put in place when they were banned. Combined with proper systems engineering to avoid leaks that are now required due to the refrigerants being extremely flammable or generally dangerous to human life we would both solve the problems of them being in the atmosphere, while avoiding the engineering problems of designing AC units that have to compress azeotropic compounds to extreme pressures, or function close to their critical points in tropical climates or any number of other problems with lubrication/etc.
The "problem" with R12 was that it breaks down in the atmosphere in short order (less than 10 years by some calculations). Most of the replacement refrigerants are basically inert. The estimated lifetime of r134a is 50,000 years. So even tiny leaks over a long period are going to do incredible damage to the climate. This was known from the beginning and is by design (the stable molecule bit).
But even now decades later the political ideology that AC units were the "problem" persists, despite the fact that its well documented that CFC's were used for everything from propellants in consumer products like silly string and hairspray, to large scale industrial uses like popcorn production (again recently in china).
Yet in all this time, we haven't really found a better set of refrigerants.
In the end, we would be better off bringing R12/22/etc back with the stringent controls for licensing/recovery/recycling/leak detection/etc that was put in place when they were banned. Combined with proper systems engineering to avoid leaks that are now required due to the refrigerants being extremely flammable or generally dangerous to human life we would both solve the problems of them being in the atmosphere, while avoiding the engineering problems of designing AC units that have to compress azeotropic compounds to extreme pressures, or function close to their critical points in tropical climates or any number of other problems with lubrication/etc.