Car Colors - Is White Cooler in the Desert?
I live in the desert and have always wanted a
white car. A dealer (with a green car to sell)
recently told me that a study was done - and there
is no difference in how hot a car gets based on
color! I have subjective evidence to the contrary
- put your hand on a white car in summer and its
cooler than a black car.
So - whats that truth?
white car. A dealer (with a green car to sell)
recently told me that a study was done - and there
is no difference in how hot a car gets based on
color! I have subjective evidence to the contrary
- put your hand on a white car in summer and its
cooler than a black car.
So - whats that truth?
Tagged:
0
This discussion has been closed.
Comments
As for the answer to your question, the white car will be less hot, but certainly not cool, in the desert sun.
I lived in Kuwait (it's damn hot there) for a couple of years and drove a old white Dodge Aspen wagon with a dark blue interior. It also had vinyl covered seats. The thing was deadly if left in the sun (usually didn't have a choice, not many trees in Kuwait). I had to sit on three layers of thick beach towels and use leather driving gloves just ot hold the steering wheel. I also drove a dark blue Firebird. That car had a light grey and white interior and was much cooler. I still had to sit on beach towels and drive with gloves, but it was not as bad.
I concluded that the Aspen was worse because it was a wagon and had a dark interior. All those windows did little to prevent the sun from cooking the inside of the car. The Firebird was the opposite of the aquarium-like Aspen: smaller window surface and lighter coloured interior. It did not heat up nearly as much as the wagon.
Now I live in Canada (it's damn cold here in the winter) and I would not consider buying a white or light coloured car. The reason is that light coloured cars rust much more quickly then dark cars. On a dark car, the sun will heat the metal and dry the moisture (even when it's colder then 32F), helping to reduce the effects of corrosion. With a white car, the metal would not get hot enough to evaporate the moisture, leading to faster corrosion.
A solution to keeping some of the heat out of the car is to use window tint. Some after-market window tints have a film that helps to reflect some of the sun's heat. I have also seen these solar powered fans that you stick in the window of your car (roll up the window on it). They are about two inched high. The fan circulates the air in the car, keeping it cooler.
However, I agree with that the windows are the primary route through which the sun's heat enters the car. Sunlight that strikes the car's exterior must penetrate by conduction through the frame and any insulation inside, and most of it will dispserse into the air from the heated surface instead. But any light going through the windows is basically 100% transferred to the car's interior. (The only bit that escapes is the light you see when looking into the car from the outside!) From a heat-absorbing point of view, all of the car's transparent sufaces are "black". I'd even be somewhat surprised if a light-colored interior mitigated this effect much. While it's certainly true that a light seat would reflect more heat away from itself to other parts of the car's interior, I doubt if much of that reflected heat goes back out through the windows. Maybe we could get a real physicist to enlighten us on this. :-)
My question is: How much does window tint help with keeping cars cooler in the sun? It seems that darkening the windows would block some sun from going directly to the car's interior, but at the cost of absorbing the heat into the glass itself. The heat could then be conducted to the air inside the car at the hot windshield's interior surface. You only really get rid of the heat if you *reflect* it away. Can somebody who's had their windows tinted recently comment on this? If I go to have my windows tinted after-market, what do I ask for to get the reflective stuff?
You state that a tinted window will heat up by absorbing solar radiation and then transfer this heat to the car's interior air by conduction. Well, actually most of the heat given off by conduction will be given off to the outside air(via the exterior surface of the window). And since the coating is on the exterior, most of the heat will go to the outside, since glass is not a very good conduter of heat.
I agree with the fact that tree sap and bird crap will 'bake' more on a dark car, but a good wax should help in protecting and making it easier to clean off
#9
Don't know why bedouins wear black (or other dark colors), but they usually didn't walk around in the sun during the hottest part of the day. Personally, I prefer a white t-shirt.
I think I'll get one of those shades for the windshield for next summer. I'll post the results of my experiment.
I have always felt that I want a white car (living, as I do, in Arizona). I believe it will be cooler.
A dealer - who happened to have a dark green demo accord EX V6 coupe - with all the goodies so that the sticker price as $29K - said that there had been a study done - and that white cars are actually no cooler than any other car in the desert. I mentioned this to another dealer that was bugging me over the phone - and he said the same thing.
So - true or a conspiracy to not sell me a white car!?
There is obviously some physics involved here. If the hood is hotter - does that make the inside of the car hotter? Does it wear only rubber components quicker if the engine comparment is hotter?
Having never had tinted windows, I wasn't aware that the tinting film was on the outside of the window. In fact, that comes as kind of a surprise to me. Wouldn't that make the film deteriorate much more quickly (being constantly hit by wind, rain, assorted debris, acorns, etc)?
Another Q: For years I have used Rain-X on my windows (greatly improves rainy-weather visibility, especially at night). Can you use Rain-X on an externally-applied tinting film?
Oh, and make sure they guarantee their work. Tints vary in price, UV blockage, and guarantees. Our newest vehicle has a lifetime guarantee on the tint. If you want the reflective stuff, they carry that, but not the mirror tint, as that's illegal to have.
Again, tint does make a difference in the interior heat of your car.
And, FWIW, all our cars are tinted on the inside of the window. :-)
When you say "sunscreen", are you referring to a characteristic of a tinting film or one of those auto sunshades you stick up in your windows when you leave the car? I have one of those now (the cheap folding cardboard variety) and it definitely helps keep the car cooler when I have to leave it in the sun. I understand there are nicer "space age" versions of these sunshades that reflect more heat than the cardboard. Anyone had any experience with them?
The thing that worries me most about getting my windows tinted is fear of getting a bad job. I see many cars around town whose tinting film obviously wasn't sealed properly when it was applied, causing the film to "bubble up" away from the window. Looks terrible. Even the tint on the Lexus owned by my girlfriend's mother has problems: one of the rear side windows was done so badly that it looks like you're trying to see out through stained glass. (And that tinting was done at the Lexus dealership!) Are there any tinting chains that anyone could recommend where I can avoid such sloppy jobs? Roughly what's a resonable price for a quality tinting job?
One final issue: How much does window tint impair your ability to see well at night?
No difference in night driving.
Nope, no difference in night driving, unless you get that limosine tint, which is extremely dark.
Ask around about the shop you choose; they need to be established, and to guarantee their work.
As for night time driving I find that it makes a difference when checking the blind spots (I have a fairly dark tint on the rear side and rear windshield). It definitely makes it harder to see cars at night!
I have also heard from other sources that the exterior color does not effect interior temperature of the car due to construction. The only effect is from the sun entering the windows. The sunlight passes through the windows and is absorbed by the interior colors. If the interior is a lighter color some of it will be reflected back out but not all of it. That is why the cardboard blockers work. Most are light in color to reflect the light and the light does not get reflected into the lower areas of the car.
I find that tinting reduces the heat that reaches the interior, and keeps things from fading. I recommend as heavy a tint as is legally permitted.
(the easiest way to explain it is not so easy, but can be viewed in terms of Ansel Adams Zone system)
The tinting incorporates metallic particles which in order of importance to me is filtering out UV light, and thus allows less heat in that hits inside masses which store and give off heat by conduction.
In practical terms, the air conditioner is in fan 2 speed and in darker vehicles in fan 3 and 4 speeds to maintain the same perceived ride comfort.
White reflects light. Dark colors absorb light, then radiate the solar energy as heat. In the interior of a car, here's the results. A lot of the light that's reflected off of the light colors is reflected right back out of the windows. The dark interior absorbs that light and warms the stagnant air via conduction. Thus making the darker interior color a hotter car.
How does tinting come into play? Well, it partially reflects, partially absorbs that light. Granted, there's quite a bit of light that still makes it through (otherwise, you couldn't see *grin*), but a significant portion of that solar energy is filtered out. So, what's the difference between the tint absorbing the energy and the interior? Glad you asked. First, the surface area of the tint is smaller, so there's simply less area of the car giving off heat to the interior of the car. Secondly, the tint radiates heat in both directions, inside and outside of the car. If that were the only thing in play, your car would get hot at half the rate. As it is, it helps significantly.
So, how can people say that there's no difference between the tempatures of light and dark cars. The cheap answer is, there is no difference in how hot either car gets because they'll both peak at the same temp (although I've never experienced a temp. peak). The difference lies in how fast they'll reach that temp. Again, in most modern cars, you're not going to feel too much of a difference between a dark and light car if the interior is the same color due to the engineering / insulation of the cars. However, get two cars of differing interior colors, and I'd prefer to ride in the light colored one any hot day.
Blaikm had the right idea when he said that clear is black, but I'll go one step further, clear is pure evil and of Satan. It goes back to that surface area thing; it allows for more interior space to be heated faster psi than if your entire exterior were black.
As for things baking onto your paint, that's another matter entirely. In hot states, I doubt it really matters what color your car is, anything could possibly bake into your paint and it would definitely be more noticeable on a dark car. Dark colors also fade faster under harsh conditions, but then, I don't need to tell you that.
Having said all that, I have a dark green Solara with a dark interior living in Louisiana. Intelligence? What's that?
- Slayv1
In my opinion, the windows should contribute more heat than the metal conduction. The point is how much portion either part contributes. Window 70% and metal 30%? Or simply window 100% and metal none? Can you give your opinion please?
Thanks,
Buddhaseed
"The bedouines wear black so they sweat more."
Most of the bedouin men I saw in my 2 years in Saudi Arabia wore white. The women wear black, but I think that's a cultural/religious thing which has little to do with comfort. And from what I saw of their vehicles, almost all of the bedouin's pickups are without air conditioning and painted white.
Then post the results here for the rest of us. Tell us the exterior and interior colors of both cars. It would be best if the exterior colors were dark vs. light, but the interior colors were the same.
As long as you are careful to keep everything but the car color the same, this would be a valid way of getting your answer.
In Arizona, when the air temperature is 112, I don't know what difference the paint color makes - it's intolerably hot no matter what car you are in. Thats why air conditioning and covered parking are very popular.
I found that the seat was the hottest place, the glove compartment and top console bin next hottest, the bottom console bin compartment a bit cooler, and the winner... under the passenger seat was actually as cool as in the trunk, sometimes even a few degrees cooler. That was a surprise. I have double-checked it and every time seat would be about 128 degrees and under it would be 98 degrees.
Lucky for me, my car has a drawer under the passenger seat so I now keep tapes there.
FYI, the car is silver metallic.