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normal solar irradiance

Ee,n; En

irradiance produced by direct sunlight on a surface on the Earth that is perpendicular to the direction of irradiation by the Sun

Note 1 to entry: Normal solar irradiance is not the same as direct solar irradiance, which is measured on a horizontal surface on the Earth, not necessarily perpendicular to the direction of irradiation by the Sun.

Note 2 to entry: The normal solar irradiance is expressed in watt per square metre (W⋅m−2).

Note 3 to entry: This entry was numbered 17-826 in CIE S 017:2011.

Publication date: 2020-12
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