The Measurement of Solar Radiation

The measurement of solar radiation has run the gamut from casual interest recordings to intensive scientific/technological experiments on satellites. In these situations, the interest has always been to obtain reliable, usable date. The choice of measurement technique has often depended upon availability of instrumentation and funding to design a proper data acquisition system and analysis program. The following monograph attempts to deal with some of the problems associated with the choice of instruments for such a program and with some of the questions of the techniques for the analysis of the data acquired.The first section, adapted from the International Energy Agency Conference on Pyranometer Measurements,1 provides an analysis of various characteristics of pyranometers. We acknowledge the advice of Michael R. Riches, Office of Energy Research, U.S. DOE, on the use of this material.The next section outlines some of the commonly noted problems with the measurement of solar radiation, as well as possible causes and solutions. Much of this information is based upon the recent experience of the U. S. DOE-sponsored Solar Energy Meteorological Research and Training Sites.The last section is adapted from Sunworld (Solar Radiation Instruments by Kinsell L. Coulson and Yvonne Howell) and is reprinted with the kind permission of the publishers, Pergamon Press, Ltd. Additional information has been added from recent publications.Appendix 1.1, Historical Perspective, is simply a compilation of dates and events in the history of solar radiation measurement. It provides the time perspective which has led us to today’s solar-oriented society. Much of the information is adapted from Coulson2 and Drummond,3 with input from EPLAB, Inc., Hollis Geosystems Corp., Casella London Ltd., LI-COR, Inc., and Kipp & Zonen.