On those fierce summer days—especially if you have leather seats—getting back in your car can be a real pain in the butt. Literally. We’ve all experienced that searing pain when the backs of your thighs hit leather that’s been sitting in the sun for too long and practically start to sizzle. It’s practically a summertime tradition. There are, of course, ways to prevent this. Putting a towel down is one, but both you and I know that as soon as you try to sit down that towel is going to move in impossible ways, making its existence almost as irritating as the scorching leather itself. Luckily for us, both Mercedes and BMW have come out with some treatments for their leather interiors that are supposed to lessen the effects of the sun’s rays and leave your seat cooler, so maybe you won’t have to use that oven mitt to protect your hand from your gear shifter in the future.
BMW and Mercedes Want to Protect Your Precious Bum from the Sun
Back in 2012 BMW decided enough was enough and came out with some technology that made (BMW) convertible owners everywhere heave a sigh of relief. They came out with their “sun-reflective technology” which is supposed to help keep the seats and all of the other leather bits in the car cooler in the sun by reflecting the suns rays—therefore not allowing those rays to heat everything up as much as usual.
Now in 2021 Mercedes has introduced a “sun-reflective coating” in their E-Class Cabriolet that promises to do pretty much the same thing. The real question is, how effective are these coatings—really.
Time To Put the Tops Down, Play With Lasers, and Do Some Science
Luckily enough, our friends over at Car and Driver took the time to do a somewhat unscientific (more on that later) look at how a car’s seats are affected by these various sun-reflective technologies. They started out with three cars: a 2021 BMW M440i convertible, a 2021 Mercedes-Benz E-450 Cabriolet, and a very fine (non-running) Mazda MX-5 Miata from the early 90s. They then parked these cars outside in direct sunlight on a 77 degree day, and took readings every half an hour with an infrared thermometer to see how the different seat styles held up against one another.
The highest seat temperature level was recorded by the non-technologically advanced Miata, and was a blistering 151° F. For the Mercedes, it was down quite a bit to 129°. The winner, however, was the BMW with a still pretty uncomfortable 123°F. Though this seems to make the case that these sun-reflecting technologies are super effective, it does fail to take into consideration the color and type of seats.
Does the Sun-Reflective Leather Keep Things Cool?
The hottest seats that were in the Miata didn’t have the reflective technology, but they were also the only dark grey-black seats in the lot—and also made of cloth. The Mercedes, who came in the middle of this race, also had seats in a shade lighter than the black seats—in this case a rich brown leather. And as you may have suspected, the Bimmer’s seats were a light tan leather—both the lightest shade of them all and the coolest to the touch.
Though Car and Driver did the best they could with the convertibles that they had available to them, it would be interesting to see what differences in temperature there would be from 3 convertibles with black leather seats (or brown, or tan). It this ideal testing scenario there would be one BMW and one Mercedes that have been treated with the reflective technology, and another convertible with plain black leather. Who will come out with the coolest keister then?
For the rest of the temperatures and more info on the cars they tested, stop by Car and Driver and see what you think.
