Originally Posted by dwf137
The only thing it would change is the amount of time that you could use the compressor, but NO ONE actually shuts off their AC when the temp goes low, because then you're blowing in hot air.
A/C works on a duty cycle basis with a thermostat. It doesn't run the whole time you've got it turned on, so it only uses as much energy as it needs to cool the car to the desired temp.
The less heat that enters the cabin the less duty cycle the A/C compressor runs and therefore the less energy spent on extracting the heat.
I know you're talking about cooling fresh air, but you have to realize that the cool air from the A/C is displacing hot air in your cabin when you use the vent. The less hot air that exists in the cabin the less cool you need the air that's blowing in. If you were to actually measure your vents you'd see that they're blowing out 40-50° air in order for the temperature in the car to reach 65-70°. The cabin will never be 40° inside just because the A/C is on because the sun is always adding more heat.
One of the biggest problems with cooling down a car is that it sits in the sun all day and every interior surface, as well as the air inside, gets to be 140° when you get out of work or the supermarket.. or your house. Now the A/C has to use it's 40° air to displace a massive amount of heat that could be partially avoided with minimal effort.
I don't get all the hate for this. Anti-tint laws are pure BS and this will make cars safer and nicer to drive at a minimal cost.