Sammlung: Small

The smallest units that genuinely work are 5 to 10 watt evaporative coolers about the size of a small coffee mug. They won't make a room cold, but they do a great job refreshing the air within close personal range in front of your face. Just don't buy ultra cheap $10 "ACs"; they're just fans with a water sprayer that humidify more than they cool.

Yes, for a bedroom, place it on your nightstand aimed at your face, and it will help you fall asleep more comfortably in the heat. In a car, a mini cooler easily fits in a cup holder or clips onto the dashboard and runs off USB. It won't save you from 40°C (104°F) heat, but it will make your trip or night noticeably more pleasant.

For a windowless room, choose an evaporative model with a water tank of at least 3 liters and airflow of 200–300 cubic meters per hour. These coolers need no venting, run quietly, and use very little electricity. They create a pleasant fresh breeze and make the heat much more comfortable, especially if you add ice to the water tank.