Solar Irradiance  (or  Solar radiation Energy Flow) through a horizontal surface with area of  1 m2, is measured in  W/m2  [ or equivalently in (J/s) / m2 ], as it recorded in the  visual  to  near-infrared  bands. Under cloudy conditions, Solar Irradiance is reduced accordingly.


Solar irradiance values are supplied by the Kipp & Zonen CMP3 pyranometer[†].


 [†] Spectral Range : 300 ~ 2800 nm  -  Uncertainty in daily total : < 10%