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Overly Bright with the Glass Roof

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I'm not worried at all about this because physics. If Tesla applies something that blocks 97% of UV and IR waves, then that 3% increased cabin heat from the sun is not going to make or break anything.

Let's talk about solar radiation, electromagnetic spectrum, and such:
Solar_spectrum_en.svg

As you can see from this energy / wavelength graph (from wikipedia). Most of the energy in sunlight is in the visible portion of the spectrum; almost none of it is in the UV portion, less than half in the IR portion (we are interested in the red curve). So even if you block ALL of the UV and IR, 50% of the energy is still going to get into the car. But what really gets the car hot, is that energy when it is absorbed, is (basically) converted to long wavelength IR, which since it is blocked by the glass, can't escape, so it builds up.
This is why most tints block visible light too. It would be interesting to know the actual tint levels Tesla intends to use, and whether they will vary that based on delivery location.

Thank you kindly.
 
No not to much money. I had a Miata as a daily driver for over 5 years in Houston, driving 90% of the time with the top down. But to me there is something different with the sun that comes through a window then sun light in a convertible. Not sure if it's glare or what, but it didn't bother me at all with the top down. But in my wife's car with a sunroof if the sun is directly coming in it I have to close it.

arrgghhh... you missed the joke. lol.

You can't cave too much money AND you can't have too much light. That's what I meant.

Again - Duct tape comes in black for those who don't like all that light.
 
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So, how would the various tinting options listed here compare with the Visium "glass" top?

I have one on my Roadster, and it's great. Love the open feel that it gives, the light, the whole package. In the Winter.

In the summer, not so much. Way too much solar gain while parked at work during the day, so I switch to the cloth top. The shade from black canvas is much better than the smoked Visium, and of course, I can take it off for the drive home...

In a sedan like the M3 - much bigger area - I'd be a bit concerned about the solar gain. A retractable shade would be a good idea, I would think, if it's thick enough.
 
But that 3% will be less of an effect than 100% of UV/IR passing through typical car windows in an untreated competitor car.

Unless you're driving a fully opaque, black car with zero windows then it's very possible that a Model 3 full glass roof will be less heat-prone than competitors with normal, untreated windows. A Model 3 with a solid roof will still be better than a Model 3 with a full glass roof, but if the full-glass version is still superior than everything you're used to now then what would the downside be of it?

There's of course a chance that they will screw up the Model 3 glass, not using the same solutions found in the MX/MS making me a liar. But that's unlikely as it's a solved engineering problem.

A Model 3 with a solid roof will still have an unusually big back window and windshield.

I think my smart car was a good example, as a percentage of the interior it probably had the same amount of glass as a Model 3 but it was no hotter than any other car I've driven on a hot, sunny day.

There is no truth to this - it is conjecture. What is known to be factually true is that the only other vehicle with panoramic glass - the model X - does NOT live up to the lofty standards you imagine, and many owners are complaining about how hot they are and installing third party shades.

If it is letting in light it is going to cause heating. That's reality.
 
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The MX doesn't have a pano roof. It's the larger windshield that goes right to the top of the driver and stops there. And you sit much higher in MX too.
M3 pano roof looks similar to MS. I have an MS with pano and thus far heat or brightness have not been an issue. The MS pano roof is definitely different and better than the sunroof on other cars. The sunroofs in other cars don't control as much heat and light as does the pano roof on MS.
 
There is no truth to this - it is conjecture. What is known to be factually true is that the only other vehicle with panoramic glass - the model X - does NOT live up to the lofty standards you imagine, and many owners are complaining about how hot they are and installing third party shades.

If it is letting in light it is going to cause heating. That's reality.

It's also conjecture that the Model 3 will be better than competing EVs, but given Tesla's objective track history I'm not at all worried about the glass being too hot because the vast majority of those complaining about a glass roof in regards to heat, are not owners.

As you can see from this energy / wavelength graph (from wikipedia). Most of the energy in sunlight is in the visible portion of the spectrum; almost none of it is in the UV portion, less than half in the IR portion (we are interested in the red curve). So even if you block ALL of the UV and IR, 50% of the energy is still going to get into the car. But what really gets the car hot, is that energy when it is absorbed, is (basically) converted to long wavelength IR, which since it is blocked by the glass, can't escape, so it builds up.
This is why most tints block visible light too. It would be interesting to know the actual tint levels Tesla intends to use, and whether they will vary that based on delivery location.

Both the MS and MX use factory tints as well as materials/coatings that block UV/IR, why do you think that they won't do the same on the Model 3 despite stating that they will have appropriate tints on the Model 3?
 
It's also conjecture that the Model 3 will be better than competing EVs, but given Tesla's objective track history I'm not at all worried about the glass being too hot because the vast majority of those complaining about a glass roof in regards to heat, are not owners.

I specifically stated the complaints are coming from owners. People were even asking about at the model 3 unveil and the engineer's response was to acknowledge that maybe they need to tweak their tinting.

I'm hopeful they will fix it for the 3. But acting like there is no issue is make-believe.
 
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I think my smart car was a good example, as a percentage of the interior it probably had the same amount of glass as a Model 3 but it was no hotter than any other car I've driven on a hot, sunny day.

Funny you should mention Smart Car.
My 08 Smart car w/ Lexan Roof was horribly hot, even with shade closed.
All glass was tinted too, so its the pano roof that was the issue.

Also had a 11 E550 loaner for 1 month, that had Pano.
It was horribly uncomfortable, compared to my 10 E63 w/ Sunroof and a solid closable shade.
 
Funny you should mention Smart Car.
My 08 Smart car w/ Lexan Roof was horribly hot, even with shade closed.
All glass was tinted too, so its the pano roof that was the issue.

.

Tint simply makes glass darker. If your window film does not block UV, etc. then all you have is "darker".

My wife has a brand new 2016 Kia Sorento that has glass that extends itself from the roof of the front seat all the way back to the 3rd row. The glass is clear, however when my wife opened up the roof - I feel the heat. There is some kind of coating on the clear glass roof that is blocking all kinds of heat rays from the sun. Sorry to those who are scientific geniuses and don't use the term "heat rays".

Anyway...roof closed - I don't feel anything on my bald head....roof open - I'm sweating. Its only 70 degrees today.

Oh that's right - we are talking about brightness, not heat.

BTW - Its a Tesla....who is worried about heat? Just turn on the AC before you get in ( via the app ).