High transmittance: High transmittance allows more sunlight to pass through the glass to the solar panel, thereby improving the photoelectric conversion efficiency. The iron content of ultra-white emboweled glass is < 0.015%, the visible light transmittance is > 91.5% (3mm standard thickness), the iron content of ultra-white float glass is < 0.015%, the visible light transmittance is > 91% (5mm standard thickness).