A solar radiation sensor measures solar energy from the sun.
Solar radiation is radiant energy emitted by the sun from a nuclear fusion reaction that creates electromagnetic energy. The spectrum of solar radiation is close to that of a black body with a temperature of about 5800 K. About half of the radiation is in the visible short-wave part of the electromagnetic spectrum. The other half is mostly in the near-infrared part, with some in the ultraviolet part of the spectrum.
The units of measure are Watts per square meter.
The device is typically used in agricultural applications, and is used in the calculation of Evapotransportation. Evapotransportation is the potential for evaporation of moisture from the soil (or the reverse of rainfall) and is a function solar energy, wind and temperature.