January 1, 2010.
The definitive version is available at http://dx.doi.org/.
In the late 1970’s the Lawrence Berkeley National Laboratory’s Energy and Environment Division developed four circumsolar telescopes for use in accurately predicting the performance of solar thermal conversion systems using focusing collectors, and to determine whether pyrheliometer data is adequate for estimating this performance. The instrument was designed to obtain solar radiation measurements, to measure the effects atmospheric conditions have on direct and circumsolar flux, and to incorporate measurements of total hemispherical insolation in the horizontal plane and the plane normal to the Sun’s location. The National Renewable Energy Laboratory obtained one of these instruments in order to improve upon available data and to better analyze more modern solar thermal conversion systems and instrumentation. As this instrument is fairly old and has been in a storage facility for some time, this analysis and evaluation presents recommended upgrades and considerations to be made in resurrecting an LBL Circumsolar Telescope.
National Renewable Energy Laboratory (NREL)