How to Keep Your Car Cool Without Air Conditioningby braniac
Cars are great solar heat collectors. They have windows to let the sun's energy in, and they have enough mass to keep the heat. We all have heard the warnings that a car can get so hot, it can kill a dog or small child.
And it takes a lot of AC to pump that heat out of the car once it heats up. But that can be an expensive and wasteful way to cool your automobile. (And if you have an old car, it may not even work.)
The best way to naturally cool your car, is to keep it from getting so hot in the first place.
Use a windshield sunshade. You have undoubtedly seen sunshades in the windows of cars - maybe with silly messages on them. You may even have one yourself. A car sunshade is usually a piece of folded cardboard or fabric or other material that you put up against the inside of your windshield to keep the sun out. The best ones are the shiny reflective ones, but any of them make a huge difference.
Park facing the sun. If you have a sunshade, it will shield the front seat from the sun, so you might as well park facing that direction. That way the sun won't shine in the rest of your car either. (If you don't have a sunshade, you are better off parking to face away from the sun, so that the front seat and steering wheel will not get so hot.)
Consider parking farther away if it means you can park in the shade. Yes, if you park further away, you will get hot from walking, but a short hot walk can be better than a long searing drive. Your car collects a lot of heat and it will hold onto it.
Have some water and a rag or paper towel handy. Water is the greatest way to cool hard surfaces off - such as your steering wheel. Even when water is warm, it can dissipate heat by evaporating. (That's how our sweat works.) Keep the water in a shaded area, or even fill a drinking water bottle while you are away from your car and bring it back with you. Pour the water on the cloth and run the cloth over the surface of the overheated steering wheel or gear shift or safety belt buckle. The water will carry some of the heat away as it dries. It may take a couple of passes to get the item cool enough to handle.
Crack open the windows. This one may seem obvious, but it's surprising how many people don't do this. Leave your windows open a crack to let the heat out as it builds up.