The Best Portable AC Unit uses Peltier Effect for cooling the air. It is a thermoelectric process that uses the voltage difference of two electrical junctions to change the temperature of air. The cold air is accumulated at one junction and is then ready to be used for cooling. While, at the end of the day, it is an "air conditioner", however, it can actually do much more than that. The BLAUX Portable AC can also be used as a heater thanks to the thermoelectric effect that we talked about earlier. The hot air is accumulated at the other junction, which can be used for heating purposes. Apart from that one can also use it as a humidifier or just as a fan if they desire. The BLAUX Portable AC Amazon has a fan to direct the cold air generated inside to the outside. The fan has three speeds that allow it to be used specifically as needed.