My contribution to reduce global warming

Another experiment I performed was about the exterior paint of the car. My Prius is dark gray so it is on the spectrum that absorbs most of the sun, having a scorching outside surface. It may not affect greatly the temperature inside the car but certainly increase the temperature of the air surrounding the car. I bought a thermal camera that is attached to an android cellphone (Seek) and that helped me understand better about the color of the cars and the temperature on them: it is incredible how the black cars can reach so high temperature compared with cars with white or light gray colors. 

 

But also colors like red gets really hot.   Well, painting my car to white is a very expensive option, so first I bought a couple of plastidip cans, and painted the hood on white, and then added some Jedi symbols on it with vinyl cut with my wife’s cricut. There was really a difference on the temperature of the hood compared with the surroundings. The downside of it was that the surface looks rough, I mean, I am not a professional painter and using a can to paint the hood is not as simple as you can think of.

 I ripped the plastidip and paint it again with it trying to be more careful, but still I was not totally OK with the results. So I kept it that way until winter when there is no longer need to keep the surrounding of the car cool.   

Before the next heat season, I brainstormed other ways to keep the outside of the car cool, and I hoped I could chrome my car. But thinking about the chroming process, it looked as an impossible idea. Then our friend Google images let me discover that you can actually chrome your car using vinyl! In fact, some guys chrome the complete car that way. But for my budget it would be too much money for my experiment.  I calculate if I take it to a shop they will cost around 500 dollars to, so I looked on amazon and eBay and I could get the vinyl, on several colors also. I bought a 10 dollar sample, just enough to cover the “black” spoiler of my Prius.

 I got the gold color because I thought it will combine with the silver/chrome if I decided to go this way. I discovered that applying the vinyl is not like covering the books when you were at school; it is a little bit trickier. But well, it was just the first trial and it looked good, the only back draws is that after a couple of months it started to discolored a little bit.  But well, I bought the cheapest vinyl as possible, not the 3M that can last more. So with that practice I purchase now the chrome/silver vinyl and installed it on the top flat surfaces of the car which are the ones that gets most of the sun. I really liked the look, half up of the car was reflecting the sky, the blue with the clouds, and it looks really nice.

 Measuring the temperature of the metal, it was a very big drop compared with the original dark gray areas. 

  Also measured the sun shade, and it was so much cooler.

They said that the cheaper is sometimes expensive; I installed them on April, and since July I started to see some degradation on the silver chrome: first on the sunroof it started with black dots that started to grow, then I tried to take off some portions of the frame of the window and it leaved shiny residues that will require me to use a heat gun to take them off.  Then on the Hood I just started to see the black spots I originally saw on the moon roof. I will wait until fall or winter to take it off, hopefully without damaging the paint of my car. But I may consider buying this time the 3M vinyl, hopefully it is not that expensive as the $80 dollars that the cheap vinyl cost me.

Preventing heat absorption in my Prius

Sun, heat and it consequences are always on my mind here on south Texas where you have high temperatures and high humidity therefore high heat index.  The last project I shared here was how to make my Prius more comfortable when riding back home from work. I tested the solar roof vented effectivity which resulted a very expensive option when bought my car and that a cheaper windshield sun shade would work better.  I made my own buying reflective Mylar and some corrugated carton which prove to be good but difficult to store inside the car, at least it lasted a couple of years. Later I have an idea to take the sunshade out of the car, so that the heat absorbed by it will be dissipated outside and not trapped inside.  Using the same reflective Mylar I bought before I cut it to the size of the windshield, and added some strong neodymium magnets so that it can be maintained in place. It worked great, except when there was some high winds which sometimes unsticked the magnet and have it hitting my glass. Thinking, millions of brains may have better ideas, I checked on Alieexpress  (Chinese version of amazon, where it takes like a month to receive your purchases from China), and found that they already had a similar idea: A reflective cloth on one side, and a soft cloth to prevent scratches or rubbing with the car body, and instead of my magnets they made some longer ears that you insert on driver and passenger doors just before closing them. 

I tested it for a year, but unfortunately the reflective cloth started to degrade and suddenly I got glitters inside my car. 

Next year I bought it from a different brand, this time it looked better, stiffer, and the side pointing to the car was black preventing any reflection of the internal heat. Unfortunately the degradation of the shiny side started after a few months too.

Placing the sunshade on and off takes time, practice until you dominate it, but it is not convenient. Thinking that the main source of heat for the car is the black dash absorbing the sun energy I considered those “carpet” like mats that you place over your dashboard. Knowing already that black colors absorb more energy than whitish colors I discarded those dark mats, but I was worried about the glaring that will come from it.  Finally I decided for a light gray mat, and as thought the glare is really annoying because it is reflected on your windshield to you so it is not good for your eyes. Fortunately I have polarized eye glasses that almost eliminated the glare, so with them it is more comfortable. 

From my previous experiments I decided that the interior temperature when entering the car when leaving work is the best variable to measure, so instead of having the temperature recorder all day I just bought a small thermometer that I installed in my dash on the area that the sun does not touch it. 

Does not require battery so it is convenient.  Coming back to the mat, I checked no significant improvement on temperature having the sun shade and the mat, but having only the mat it was like 5 or less degrees Celsius hotter than with the sun shade on. It is not that bad, considering that the sunshade alone reduces around 20C, so I can estimate the mat reduced 15C.