Is air conditioning not a standard feature in cars? Should it be?

Talk about a trolling thread, the number of people who have swallowed the sales bullcr*p about Air Conditioning is incredible.

Air conditioning is a complete mis description of the function. Air Chilling would be more appropriate, and it is so often misused it's not even funny.

If the A/C only is on, then air coming into the vehicle is cooled, (which also reduces the humidity of that air) and that's ALL that A/C can ever do. The air is chilled, which is costing the owner/Driver a specific sum to do that, due to the use of additional energy to drive the compressor that produces the air conditioning effect (its exactly the same as a domestic refrigerator in terms of how it works). To make it worse, the chilled air is LESS able to remove ice or mist or condensation from the windows, as the colder air is, the less moisture it can absorb.

So, to defrost, or demist the windows, heat is required, which can ONLY be provided by the use of a separate radiator that is in the air flow line, and which is heated by the water from the radiator (with the exception of modern electric powered vehicles), which requires that the engine is running, and producing heat. The warmer the air is, the more moisture it can absorb, which helps the process of clearing the windows. To confuse the equation even more, when water freezes, (transitions from vapour to ice) energy is released. So, if the A/C is on, the air entering the cabin may be less humid than the air outside, but it will also be cooler than it would otherwise have been, as the heat side has to warm the air more than if the A/C was off.

The exact physics of the energy required or released in the process of condensing or evaporating moisture is a lot more complex than that, so probably not appropriate here, I can remember some of it still, as it was required learning in the meteorology part of commercial aviation training, as part of understanding clouds and their formation, and it was a severe brain strain at the time. This whole subject is the explanation of why it doesn't often rain hard when the air is cold, as there's not the same amount of water vapour in the air as there is when it's hot.

As for climate control, or manual control, all that is doing is regulating the exact mix of air temperatures and cooling from the air conditioning and heating systems to provide air into the cabin at the temperature desired by the operator, with climate control doing the job automatically.