pyroheliometer

pyroheliometer

[‚pī·rō‚hē·lē′äm·əd·ər]
(meteorology)
An instrument that measures the sun's radiation output.
References in periodicals archive ?
The classification is based on two parameters; the fraction of time, s, that the direct normal irradiation (measured using a pyroheliometer) exceeds 120 w/[m.sup.2], and U, the natural logarithm of the average of the absolute values of the change in global horizontal illuminance (lux) over a one-minute span.
Direct normal irradiance was measured using a tracking pyroheliometer. Sky type was computed from direct normal irradiance data using the Darula-Kittler (2004) sky classification.