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Comment by VladRussian2 | Hacker News Reader

>You are very right and I dont see how they might have foreseen this.

as it was already mentioned this architect had already built death ray building in Las Vegas

>It is quite unusual for the windows on a building to start melting cars, especially in a mild climate like London.

Sun's potential energy flux on the Earth's surface, be it Las Vegas or London, is 1KWt per m2 of the surface _perpendicular_ to the flux. So given clear day and good angle (close to perpendicular) of a building to the Sun's light, the building will be beaming back significant part of that 1KWt/m2.

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If the car is hotter to begin with because of the air temperature around it then the melting point on a component of the car will be reached faster. So if it was in a much hotter place like Las Vegas where the sun shines a majority of the time I could see things like this happening more often.

Instead of mild I should've said rainy or cloudy place like London.

A minor point, it's at its peak of 1kWm-2 when the sunlight is perpendicular to the Earth, that is, when the sun is directly overhead, because that's when it has to pass through the least atmosphere. Sunlight reflecting off the building where the sun is not directly overhead will necessarily be less intense.

A minor point, the direct peak intensity is not 1 kWm^-2 at AM 1. AM1.5G is the standard spectrum and it is acquired at an oblique angle of 48.2 degrees from zenith. It is typically normalized to 1 kWm^-2 due to the inherent variability encountered when actually trying to measure these things.

Er, yeah, that's kind of the point :)

For London in Autumn/Winter will have a surface normal of z~=60-70 degrees to the Sun. Much greater than 48.2 degrees, so the peak insolation must necessarily be less than 1kWm-2.

SI pedantic, I know, but: What in the name of Tesla is a KWt? Perchance you meant KW?

yazmeya: your account appears as [dead] (aka hellbanned).

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