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solar factor, <of glazing material>

total transmittance, <of glazing material>

total energy transmittance, <of glazing material>


quotient of the quantity of heat penetrating into an interior through the glazing and the solar radiant energy incident on that glazing

Note 1 to entry: The solar factor is the sum of two quantities: the radiant transmittance, τe, of the glazing and the quantity equal to the quotient of the convected and radiated heat gain from the glazing into the interior, Q2, and the solar radiant energy, Q1, incident on the glazing:
g = τe + Q2 / Q1.

Note 2 to entry: The solar factor has unit one.

Note 3 to entry: This entry was numbered 845-09-106 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-1199 and 17-1322 in CIE S 017:2011.

Publication date: 2020-12
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