Jefferson Starship had a hit number about 10 years ago, "We built this country on Rock n' Roll!!" But a lot of other factors went into building the country as well, air conditioning being one of them. Cities like Dallas owe much of their development to air conditioning. Many cities, especially in the south, were only quiet backwaters until air conditioning become commonplace in the years after WWII. Dallas can be oh-so-hot in the summer months and unpredictable weatherwise because it is situated at a point where the warm moist air masses from the gulf collide with the cooler, drier continental air masses. Air conditioning changed all that, the weather inside could remain consistent while outside it did it's usual unpredictable thing. One can't overstate the importance of air conditioning and its effect on the nation's economy over the past 40 years.
Now the federal government seems hell bent on making all forms of refrigeration more expensive, but less efficient at the same time. They've singled out automotive air conditioning for the worst treatment which will cost consumers billions in the next several years. Chlorine-based refrigerants have been refrigerants of choice for 50 years now, inexpensive to manufacture and reasonably efficient they are used in millions of refrigeration devices from walk-in coolers to residential air conditioning units.
Back in the 70's, people started thinking about the environment and its protection. I think few will argue that dumping untreated wastes into rivers, excessive use of phosphates in agriculture, and sulphur dioxide emissions which turn into acid rain, and many other forms of pollution need to be abated. There is hard evidence of the effects of these forms of pollution. Chlorine bearing refrigerants came under attack in the 80's when some people speculated that chlorine was causing the ozone in the atmosphere to break down and levels of ultraviolet light were increasing causing grievous damage to flora and fauna alike. No conclusive evidence of the effects of chlorine bearing refrigerants in the atmosphere has ever seen the light of day, only reams of speculation about its effect.
After the Montreal protocols were signed in 1987 where many countries agreed to phase out the production of chlorine-based refrigerants, the EPA went nuts and went on a crusade to stamp out chlorine-based refrigerants as fast as they possibly could. Rather than to provide for an orderly phase-out of such refrigerants, they mandated that production and importation of such refrigerants cease after 1995 leaving millions of consumers in the lurch faced with costly retrofits. All new vehicles from 1994 onwards have been produced using the supposedly environmentally benign refrigerant R-134A. So where does this leave the millions of consumers with vehicles using the "dangerous" R-12, in a word no where!! R-12 will continue to be available in small quantities (at very high prices) but only to "top" systems off rather than for complete recharges. Consumers needing major repairs such as a compressor replacement will have no choice but to have the system retrofitted for R-134A. These retrofits won't come cheap either as they involve replacing most of the major components in a vehicle's air conditioning system. The compressor, receiver-drier, all hoses, expansion and throttling valves, and pressure modulators have to be replaced at a cost of $700 and up. There are no "drop-in" replacements for R-12. It's not that industry can't develop a drop-in replacement, they have. But the EPA has consistently refused to approve such refrigerants for vehicle use, although they have approved some of them for stationary use. R-406A (ASHRAE designation) which was developed by an inventor in Indiana and produced by a small welding supply company has proven to be viable drop-in replacement for R-12 and is 95% less chlorine bearing than R-12. It is fully compatible with mineral oil based lubricants used in R-12 systems and is just as efficient if not more so than R-12. The EPA has so far refused to approve it. OZ-12 is another replacement the EPA refuses to approve. In the case of OZ-12, EPA won't approve it because it is minimally flamable. I guess the fact that motor vehicles are propelled by extremely flamable substances is lost on the EPA. In a crash severe enough to breech a vehicle's air conditioning system it is highly likely the system carrying the gasoline will also be breeched which in most cases would render the flamability of refrigerant moot. It's classic case of the government double-thought, they are the only ones who know what is better for us. So as it stands now, R-134A is the ONLY refridgerant approved for vehicle use is likely to remain so. The auto industry isn't interested in drop-in replacements and if anything has lobbied against their approval. As long as the question of replacement refrigerants and costly retorfits exist, they know it will drive some consumers into the showrooms to ante up for a new car when they might have been content with their current car otherwise. The major chemical companies aren't interested either because the replacement market is fairly small compared to bulk sales to automotive industry and they don't want to risk antagonizing their most important clients with a product that is viewed as extending the useful life of existing vehicles. Well the EPA listens to the "big boys" and their policy is determined by what they want and not by what makes the most sense for consumers.
It would have made far greater sense to allow R-12 to be available in sufficient quantities to service all those millions of vehicles that use it. Sure, we can require that R-12 be carefully controlled to minimize excessive venting of it into the atmosphere and require repair shops to ascertain the integrety of an air conditioning system before it leaves the shop with a charge of R-12. Most people wouldn't object to reasonable proceedures to minimize venting of R-12 into the atmosphere. Given that the average life of car is around 10 years, by 2004 practically all of cars using R-12 would have gone to the crusher. (the R-12 being withdrawn before the car is squashed) One big problem with R-134A retrofits is that they don't work very well in systems designed around R-12. So even after you pay big money for a retrofit, you end up with a system that you'll have to run at full blast all the time to get the desired effect. This is a classic example of government bureaucrats not seeing their noses despite their faces!! Maybe their mandated R-134A retrofits may help the ozone, but the rest of atmosphere will be fouled with increased hydrocarbon emissions, CO, and oxides of nitrogen because the increased energy demands of this less efficient refrigerant. So all the EPA has accomplished is transfering one source of pollution to another source. A nice ozone-rich stratosphere might be nice to have, but whatever benefit we might derive from that would probably be mitigated by a troposphere increasingly befouled by unburned hydrocarbons, CO, and nitrogen oxides.
They know full well that we'll dig deep to "keep cool." We'll either trade-in that old R-12 refrigerated beast or pay a small fortune for a retrofit. They win either way, it's just that we get screwed along the way and the environment is no better off for it!!