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Imagine leaving your car in the parking lot of a grocery store. You come back and 45 minutes later and when you open your car, it's hot enough to turn the ice cream back to milk in five seconds flat. How did it get so hot, so quickly?
Here’s a sobering thought: On a 70°F day, the inside of your car can reach temperatures of over 115°F after only an hour in the sun. We’ve all gotten into our cars and thought, it’s too hot in here. If you've ever gotten into your car and mistaken your seatbelt for a branding iron, you should read this article. We've got the skinny on why your car gets so hot and what you can do about it.
There’s an old adage that energy can’t be created or destroyed. When sunlight passes through your windshield it gets absorbed by your car seats and dash and then converted into heat. In scientific terms, heat is the vibration of molecules. Since most people keep their windows closed when they park, the heat becomes like a wave machine in a pool, the vibrations get trapped and amplify. That’s why even during a relatively cool day, the inside of your car can reach monstrous temperatures.
When you’re forced to park in the sun, a sunshade is the way to go. A physical barrier prevents the higher-energy waves from passing through your windshield and heating up the interior of your car. Keeping out the UV rays also helps prevent fabrics and dashboards from fading. A1 Shades makes a windshield shade with over 2,000 5-star reviews.
A study done in the journal Pediatrics showed that cracking the window just two inches can lower the temperature by up to 28°F. To be fair, the temperature of the car was still 122°F, but that’s still better than the 150°F it would have been.
To reiterate the (hopefully) obvious: that is far too hot for any living thing. Do not leave your pets or children in a parked car, even with the windows cracked, for any period of time. A temperature of 122°F can be fatal.
Technically, it’s turning your car into a bellows, but whatever. Roll down the passenger-side window, but keep the rest of the windows rolled up. Then proceed to open and close the driver’s side door a dozen times. By the time your done, all the hot air inside the car is exchanged for slightly less hot air outside. We found an article that showed that this method is even more effective than blasting the A/C when first getting into your car.
One of the major reasons why your car gets so hot in the summer is that your seats are made of materials that absorb energy well. If you throw a blanket or towel over your seats, that sunlight won’t turn to heat as efficiently.
This trick is especially useful for kid’s car seats. When you get in your car, simply remove the towels and store them in your trunk. (Bonus: spare towels are super useful with kids, whether it's giving them something dry to sit on after an accident or drying off slides after a quick summer shower.)
The most expensive option, but also one you don’t need to think about. The tint blocks out a portion of the solar radiation, helping to bring down the temperature. Just make sure to keep in compliance with your state’s laws about how tinted certain windows in your car can get.
This sounds counterintuitive, but exchanging as much air as possible is in most cases the fastest way to cool down a car. When you drive with the windows down and the air conditioning going, you’re forcing the hotter air out and replacing it with cooler air. This method works quicker than just blasting the A/C alone with the windows up. After about 30 seconds you can roll the windows up.