[brian_]

The voltage is an issue. Air conditioning takes a lot of power, and electrical power is voltage multiplied by current, so to avoid excessively high current it is better to run at high voltage. A typical car's 12-volt electrical system can't produce enough power to run an air conditioner, so electric air conditioning is usually found only in hybrids or electric vehicles, running from the high-voltage battery. As a result, the experience of EV builder with electrically-powered air conditioning is usually with systems powered by about 100 to 400 volts, not the 12 volts available in a conventional car.

There are 12 volt systems mostly used in the custom car market, for older vehicles that were not available with air conditioning.

 

[brian_]

I see, so these systems don't use something like a transformer etc to run from 12v up to 300, they are already 300v systems?

Right - it is much less expensive to build a motor for the correct voltage than to build for the wrong voltage and also provide a voltage converter.