Daily solar energy amounts are estimated using data in the visible
portion of the spectrum which come from the Geostationary Operational
Environmental Satellites (GOES). Simple physical models of radiative
transfer for the clear and cloudy atmosphere are used with these data to
evaluate whether a particular location is cloudy or clear and, if cloudy, to
what extent clouds have depleted the solar beam. Usually, about eight to
twelve individual GOES images are used during the course of a day to make
estimates of the solar energy at the satellite image times. These
instantaneous estimates are later summed to produce the daily solar energy
totals.
