Dirty Pictures and wishful thinking...

[S.H.Peterson]

NOW I gotta go back and look....

YES, you are absolutely correct!

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[israndy]

Wait, a black car absorbs more heat that the AC has to cool? How is that? Perhaps some heat in the frunk that a silver car wouldn't have but are you saying that the doors that have an open to the air gap before the interior panel is passing more heat into the car than a silver car? That makes about as much sense as a warm piece of metal weighing more. The roof and the windshield will allow the sun to warm the car, but they are identical, independent of the paint color.

 

[cvalue13]

Wait, a black car absorbs more heat that the AC has to cool? How is that? Perhaps some heat in the frunk that a silver car wouldn't have but are you saying that the doors that have an open to the air gap before the interior panel is passing more heat into the car than a silver car? That makes about as much sense as a warm piece of metal weighing more. The roof and the windshield will allow the sun to warm the car, but they are identical, independent of the paint color.

are you questioning whether dark colored vehicles get hotter, outside and in, than light colored cars?

 

[CyberGus]

Wait, a black car absorbs more heat that the AC has to cool? How is that? Perhaps some heat in the frunk that a silver car wouldn't have but are you saying that the doors that have an open to the air gap before the interior panel is passing more heat into the car than a silver car? That makes about as much sense as a warm piece of metal weighing more. The roof and the windshield will allow the sun to warm the car, but they are identical, independent of the paint color.

https://phys.org/news/2011-10-silver-white-cars-cooler.html

Silver and white cars are cooler, says study
by Nancy Owano, Phys.org

(PhysOrg.com) -- From an environment standpoint, silver and white cars are cool; black cars are not. Researchers at the Berkeley Lab Environmental Energy Technologies Division (EETD) say that the color of your car affects your car's fuel economy and how seriously you contribute to pollution. A light-colored shell reflects more sunlight than a dark car shell. The cooler the color, the cooler the cabin air, and the less of a need to run your air conditioner.

Ronnen Levinson, scientist in the Heat Island Group at Lawrence Berkeley National Laboratory, is lead author of the study. The research was published in Applied Energy.

The researchers had two cars in the sun for an hour, one black and the other silver, parked facing south, in Sacramento, California. The silver Honda Civic (shell SR 0.57) had a cabin air temperature of about 5-6°C (9-11°F) lower than an identical black car (shell SR 0.05).

A silver (or white) shell would allow for a lower-capacity air conditioner as well. The cars were run through five identical cycles of soaking in the sun. Each cycle consisted of an hour with the air conditioners off, followed by a half hour of cooling with the air conditioners running at maximum. The researchers measured the roof, ceiling, dashboard, windshield, seat, door, vent air and cabin air temperatures in each car along with weather conditions in the lot.

Overall, the numbers compiled in this car-color exercise found that using white or silver paint instead of black paint would raise fuel economy by 0.44 mpg (2.0 percent); would decrease carbon dioxide emissions by 1.9 percent, and reduce other automotive emissions by about 1 percent.

Air conditioning in cars not only decreases fuel economy but also increases tailpipe emissions of greenhouse gases and air pollutants. In this sense, cool-color cars influence both the driver and the planet.

The numbers continue to take on special significance when extended nationwide. An improvement of 2 to 2 percent in fuel economy, scaled to the fleet of light-duty vehicles in the United States, represents savings of gallons of gas in the billions, if these design changes are adopted by the automotive industry.

White, silver, and other light colors are coolest, reflecting about 60 percent of sunlight but there are dark "cool" colors that can also stay cooler than traditional dark colors. When dark surfaces are needed for aesthetics or to reduce brightness, one can use special "cool-colored" materials that stay moderately cool by reflecting only the invisible component of sunlight. Solar reflective paints can decrease the ‘soak' temperature of the air in a car that has been parked in the sun.

Manufacturing designers looking more closely into recipes for pigmented coatings that maximize solar reflectance colors would find plenty of interesting research into cool colors at the Berkeley Lab. Its researchers have been looking into roofs and cool colors for some years. They have been measuring the solar spectral reflectance (reflectance versus wavelength over the solar spectrum) of commercially available pigments. The research team has developed a pigment database describing a variety of colors, including browns, blues, purples, greens, and reds, that are cool, in that they are highly reflective to near-infrared radiation.

 

[S.H.Peterson]

not to be a dirty nerd but:
Yes. If you have absolutely identical objects that have the same weight exactly when they are at the same temperature, then when one object is heated, it will weigh more. This is because the gravitational force depends on the stress energy tensor in general relativity..

However, in the sense that we are talking here, heat has three states or phases of transmission, if you will.
Radiance
Convection
Contact

darker materials absorb heat, that heat will transfer mostly through radiating it to another object or by touching another object... so the heat transfers into the interior.. interiror parts get hotter, more AC is needed to cool it down. Thusly increasing battery draw which decreases range

 

[S.H.Peterson]

https://phys.org/news/2011-10-silver-white-cars-cooler.html

Silver and white cars are cooler, says study
by Nancy Owano, Phys.org

(PhysOrg.com) -- From an environment standpoint, silver and white cars are cool; black cars are not. Researchers at the Berkeley Lab Environmental Energy Technologies Division (EETD) say that the color of your car affects your car's fuel economy and how seriously you contribute to pollution. A light-colored shell reflects more sunlight than a dark car shell. The cooler the color, the cooler the cabin air, and the less of a need to run your air conditioner.

Ronnen Levinson, scientist in the Heat Island Group at Lawrence Berkeley National Laboratory, is lead author of the study. The research was published in Applied Energy.

The researchers had two cars in the sun for an hour, one black and the other silver, parked facing south, in Sacramento, California. The silver Honda Civic (shell SR 0.57) had a cabin air temperature of about 5-6°C (9-11°F) lower than an identical black car (shell SR 0.05).

A silver (or white) shell would allow for a lower-capacity air conditioner as well. The cars were run through five identical cycles of soaking in the sun. Each cycle consisted of an hour with the air conditioners off, followed by a half hour of cooling with the air conditioners running at maximum. The researchers measured the roof, ceiling, dashboard, windshield, seat, door, vent air and cabin air temperatures in each car along with weather conditions in the lot.

Overall, the numbers compiled in this car-color exercise found that using white or silver paint instead of black paint would raise fuel economy by 0.44 mpg (2.0 percent); would decrease carbon dioxide emissions by 1.9 percent, and reduce other automotive emissions by about 1 percent.

Air conditioning in cars not only decreases fuel economy but also increases tailpipe emissions of greenhouse gases and air pollutants. In this sense, cool-color cars influence both the driver and the planet.

The numbers continue to take on special significance when extended nationwide. An improvement of 2 to 2 percent in fuel economy, scaled to the fleet of light-duty vehicles in the United States, represents savings of gallons of gas in the billions, if these design changes are adopted by the automotive industry.

White, silver, and other light colors are coolest, reflecting about 60 percent of sunlight but there are dark "cool" colors that can also stay cooler than traditional dark colors. When dark surfaces are needed for aesthetics or to reduce brightness, one can use special "cool-colored" materials that stay moderately cool by reflecting only the invisible component of sunlight. Solar reflective paints can decrease the ‘soak' temperature of the air in a car that has been parked in the sun.

Manufacturing designers looking more closely into recipes for pigmented coatings that maximize solar reflectance colors would find plenty of interesting research into cool colors at the Berkeley Lab. Its researchers have been looking into roofs and cool colors for some years. They have been measuring the solar spectral reflectance (reflectance versus wavelength over the solar spectrum) of commercially available pigments. The research team has developed a pigment database describing a variety of colors, including browns, blues, purples, greens, and reds, that are cool, in that they are highly reflective to near-infrared radiation.

whats is funny is that it took a study by research engineers to learn what my butt in shorts in the summer on a vinyl seat already intimately understood.

 

[Deleted member 17810]

We need a nerd emoji in the like submenu.

Spoiler

looking at you cvalue too!

 

[S.H.Peterson]

?... this?

 

[israndy]

The researchers had two cars in the sun for an hour, one black and the other silver, parked facing south, in Sacramento, California. The silver Honda Civic (shell SR 0.57) had a cabin air temperature of about 5-6°C (9-11°F) lower than an identical black car (shell SR 0.05).

Oh, you were talking HONDAs on this Tesla site, you got me confused, I thought you were talking about Tesla vehicles that have glass roofs and no paint over the cabin at all. Now if you were talking about black leather as opposed to white leather, I get that.

Still don't buy this nonsense about heat being heavy. Put a pan on a scale, weigh it, then heat it on the stove, now weigh it again, gosh, it's the same. Shocker

 

[S.H.Peterson]

In the real world of experience.. no, you will NOT see a weight difference. You would need a gravitometer and 1000+ deciml point resolution scale.

 

[bdmridgeback]

I am researching whether or not these 'CERAMIC' surface coatings will be effective...

Not on Stainless

 

[Crissa]

not to be a dirty nerd but:
Yes. If you have absolutely identical objects that have the same weight exactly when they are at the same temperature, then when one object is heated, it will weigh more. This is because the gravitational force depends on the stress energy tensor in general relativity...

...Which is an unproven mathematical model of gravity that only operates at a scale too small to be measured at the size of a truck.

-Crissa

 

[S.H.Peterson]

...Which is an unproven mathematical model of gravity that only operates at a scale too small to be measured at the size of a truck.

-Crissa

oh you picky pick person! You know we dissect things to a quantum level around here! We have photometric proof, even!

 

[S.H.Peterson]

Not on Stainless

There is a local brewery pub (Goat Island Brewing) that has huge polished stainless steel tanks out in the open where they are easily seen by walk in traffic.
They use IGL AEGIS on thier tanks. Water, dirt, and fingerprints just dont seem to stick to it.
I think it would work fine on the CT..

 

[cvalue13]

I thought you were talking about Tesla vehicles that have glass roofs and no paint over the cabin at all.

still, the color of the rest of the vehicle matters. Heat comes from all sides (including under), and radiates in all directions.

In 90° weather in a parking lot, an all black Tesla’s cabin temperature will be as much as 10-15° hotter than an all white Tesla, and take as much as 2-3 times longer for the AC to cool off.

Conversely, in a 30° weather parking lot, an all white Tesla’s cabin temperature will be 5-10° coolder than an all black Tesla, and take 2-3 times longer for the heater to warm up.

If a person cares, then buy white in Texas, black in Wisconsin.



? -> (nerd with transition lenses)

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