The Sunshine Pyranometer is a patented, meteorological class instrument, with built-in heater, designed for long-term outdoor exposure.

The Sunshine Pyranometer uses an array of seven, miniature thermopile sensors and a computer-generated shading pattern to measure the direct and diffuse components of incident solar radiation. The shading pattern and thermopiles are arranged so that at least one thermopile is always fully exposed to the solar beam, and at least one is fully shaded from it, regardless of the position of the sun in the sky. All seven thermopiles receive an equal amount of diffuse light. From the individual thermopile readings, a microprocessor calculates the global and diffuse horizontal irradiance and from these values an estimate of sunshine state is made.

• Global (Total) and Diffuse irradiance in W.m-2
• WMO sunshine threshold: 120 W.m-2 direct beam
• No routine adjustment or polar alignment
• No moving parts, shade rings or motorized tracking
• Works at any latitude