Bounties attract serious brainpower to the challenge.
I went to the beach and parked my car in the sun. I entered the car after two hours and it was terribly hot inside. No matter how expensive and modern is the car, there is still no easy and efficient method of how to keep your car cool while exposed to the sunlight. There are active methods of opening the windows, putting the shades and reflecting materials on the windshields, or turning the AC before you plan to go, but they require the engine or the system running, are not so efficient, plus opening the windows can help your car being hijacked.
My idea is to use nanocoating that would prevent the heating of the car. Scientists already developed nanocoatings that would help to reduce the heating of the asphalt , but I would like to use something like vanadium dioxide, whose optical transmission changes with temperature were described in 2017 . While cool, vanadium dioxide is transparent to the IC. As soon as the temperature rises, it reflects IR, which drastically slows down the further heating of the underlying material.
The nanocoating should be in the form of liquid, easily applicable, non-toxic and transparent for the visible light at all temperatures.
Using the same technology to develop cooling clothes
Povilas SJul 19, 2021
If proven to be effective with cars, the next step could be to use similar nanocoatings on textiles to develop clothes that keep you cool in summer in direct sunlight. Since nanoparticles are extremely tiny, perhaps it would be possible to spray thin cotton clothing with them and such a fabric would still be breathable. Or even better - the threads from which the fabric is made could be evenly and entirely covered in such coating, when woven into fabric they would naturally form gaps allowing air and humidity to pass, just as ordinary threads. As a result, some sunlight would pass through the gaps, but the heat would be greatly reduced anyway. However, in the latter scenario the coating would also reflect back the IR emitted by the body, so it might not be the best approach.
Please leave the feedback on this idea
Lotions can be made out of this Type of Nanoparticles to Reduce the Effect of Direct Sunlight on the Skin
Samuel BelloJul 28, 2021
A lotion that is produced with such nanoparticles can be used to protect one's skin from too much exposure to sunlight. This will help to prevent sunburns and reduce the heat felt by parts of one's skin that are exposed to sunlight.