gshepherd wrote:Seems like there should be a way to embed some sort of coating or material in the windshield that would reject high-angle light. I understand the 3M Crystalline film has this feature, but it is not legal everywhere to apply film to the windshield even if it alllows >90% visible light through.
Imagine not only the heat reduction but also reduction of the reflected image of the dash in the windshield that creates a dangerous reduction in visibility on bright days. I wear polarized sunglasses in the car for that reason.
The Federal Motor Vehicle Safety Standards mandates the design and construction of many things in an automobile, and one of them is glass. For passenger vehicles, they are especially stringent; that's why no vehicles are allowed to have factory tint on the front windows (except for a strip along the top of the windshield) greater than about 95% or so transmittance, and why only trucks and SUVs are allowed to have dark tint on the back windows from the factory.
FMVSS is likely why the coating you speak of is not currently on car windshields.
Blue Ocean 2012 Leaf SV, lost that 1st bar at 34 months/26,435 miles. Lease returned 2 months later. Final LeafStat figures: 225 Gids, 17.44 kWH, SOC 91.89%, SOH 82.36%, 69.49% HX, 54.57 Ahr, battery temp 61.8 F.
Now driving a 2015 VW eGolf SEL.