Concentrating parabolic collectors: A patent survey

A detailed patent survey of various types of low and intermediate temperature concentrating collectors is presented. The survey examines the progress in the area of concentrating collectors (mostly novel concentrators) since 1978. The review shows a considerable decline in the amount of invention in solar energy in the 1980s, although many innovative ideas exist for improved solar energy collection and application. Recent developments have been focused on the high temperature range and power towers (dish, heliostats, etc.). Even though solar energy is free and clean, little has been done to utilize fully its potential for meeting our energy needs. This survey summarizes and provides this information in an organized manner. We will trace the progress of work done since the energy crisis of the seventies and examine what has to be done to renew interest in solar energy collection, especially now that the world's attention is being drawn to the environment. The high temperature, central receiver system, mostly used for electric power generation, is briefly discussed.