Everyone knows the feeling: you return to your car parked in the sun after a few hours at the lake or after shopping, open the door, and are hit by a wall of scorching heat. The steering wheel is too hot to touch, the seats burn your skin, and the air is stuffy. A hot car is not just uncomfortable—it can also be dangerous.
In this comprehensive guide, we'll explain why your car turns into an oven and give you the best, practical tips to avoid the heat in the first place, cool down the car in a flash, and get through the summer safely.
Your car turns into a heat trap due to the greenhouse effect. Short-wave solar radiation penetrates the glass windows. Inside, it heats up surfaces like the dashboard, seats, and steering wheel. These heated surfaces then radiate the heat back as long-wave infrared radiation. However, this long-wave radiation cannot easily escape back through the glass. The heat builds up inside.
The shocking facts: Even on a mild summer day with an outside temperature of 25°C (77°F), the temperature inside a closed car can rise to over 45°C (113°F) in just 30 minutes. After an hour, it can exceed 55°C (131°F). The black dashboard can even reach temperatures of over 70°C (158°F)!
The best method is to minimize heating from the start. A few simple tricks can make a huge difference.
This is the easiest and most effective tip. Always look for a shady spot—under a tree, next to a tall building, or in an underground garage. Even if you have to walk a few extra meters, your future self will thank you. If full-day shade isn't possible, consider where the sun will be throughout the day and park accordingly.
A reflective sunshade for the windshield is a small investment with a big impact. It reflects the sun's rays before they can heat up the dashboard. Tests by the ADAC (German Automobile Club) have shown that this can reduce the temperature on the dashboard by up to 40°C (72°F).
A light-colored towel over the steering wheel and seats (especially dark leather ones) prevents them from getting unbearably hot. It's a simple trick that makes getting in immediately more pleasant.
Leaving the windows cracked by a tiny gap can help reduce heat buildup as hot air can escape. But be cautious: this is a security risk (theft), and in a sudden summer shower, it can rain into the car. Use this trick only if you are parked in a safe area and no rain is forecast.
Sometimes parking in the blazing sun is unavoidable. But don't worry, with these methods, you can get the heat out quickly.
This method is surprisingly effective and works without air conditioning.
Why this works: By "fanning" with the driver's door, the hot air inside is actively pushed out of the open passenger window and replaced with cooler outside air. You can lower the temperature by 10-15°C (18-27°F) in less than a minute.
Many drivers use their air conditioning inefficiently. With the right strategy, your car will cool down faster, and you'll even save fuel.
A hot car is not just unpleasant; it poses serious risks.
The summer heat in a car is a serious matter, but it is manageable. By parking smartly and using sunshades, you can prevent the worst. And if your car does turn into a sauna, you now know the fastest methods to bring it back to a comfortable temperature. Always remember: a cool car is not only more comfortable but also safer. Stay cool and enjoy the summer!