The Performance of Flat-Plate Solar-Heat Collectors

Abstract The great magnitude of solar-energy flux on the earth has stimulated a number of attempts at its more effective utilization during the last 60 years. Mouchot (1, 2) and Pifre (3, 2) in France, Shuman (4) in Egypt, Ericsson (5), Willsie (6), Shuman (7), and more recently Abbot (8) in America are but a few of the names associated with attempts to prove the economic feasibility of converting solar energy to heat and transferring that heat to the working fluid (steam, air, and sulphur dioxide have been used) of a heat engine. Recently Dr. Godfrey L. Cabot has made possible a continuing research on the problem by establishing an endowment at the Massachusetts Institute of Technology for studying means of more effective utilization of solar energy. Four projects are under way: three in the fields of photochemistry, photoelectricity, and thermoelectricity. The fourth follows the conventional attack on the problem, namely, the collection of solar energy in the form of heat in a fluid and the utilization of that heat. The present paper is a first quantitative report on progress in the last field.