Harnessing the sun

Dr. Eisenhower, Johns Hopkins University president, opens this tenth season of Johns Hopkins television. Lynn Poole discusses increasing U. S. energy needs and predicts that the world may run out of coal in 1000 years and oil in 100 years, making solar energy a critical commodity. A film clip shows the sun's surface and its energy generation is discussed. John Yellott, executive director for the Association for Applied Solar Energy, says that space heating will be the first large use of solar energy. He explains the workings of a solar-heated house with auxiliary heat pump designed by University of Minnesota architecture student Peter Lee and engineered by Bridgers and Paxton. According to Mr. Yellot, the basic instruments of solar energy are collectors, concentrators, photoelectricity, and photochemistry. He shows how solar stills can convert salt water into fresh; solar furnaces can be used for metallurgy and other research; and solar stoves can be designed for arid countries where fuel is scarce. Mr. Poole uses a photo flood light to light a cigarette and shows how selenium cells operate a photoelectric exposure meter and 8mm movie camera. Mr. Yellott demonstrates a radio/phonograph developed by Admiral Corp. to run on solar cells with backup storage batteries. Mr. Yellot concludes that at this time large scale uses of solar energy are too expensive, but solar is ideal for small amounts of energy in isolated places. More research is needed in harnessing this inexhaustible source of power.