In Episode 3, we introduce you to the period between 1940 and 1970.
1940s – 70s– Dr. Maria Telkes in the USA researched several combination types of solar cookers, including some with heat retention chemicals (Halacy, P. 4) and published a book, Solar Ovens, in 1968 (Hoda, 1981, p. 5). 1945– Indian pioneer Sri M. K. Ghosh designed the first solar box cooker to be commercially produced (Hoda, p. 5). 1950s– Water heaters were popular in Florida until electricity rates fell with plentiful, government-subsidized energy, and consumers were urged to use more and more (Sklar & Sheinkopf, 1995).
Indian scientists in government laboratories designed and manufactured commercial solar ovens and solar reflectors, but they weren’t readily accepted, partly because there were still lower-cost alternatives. Farrington Daniels and George Löf at the U. of Wisconsin, USA, introduced concentrator cookers in northern Mexico, with some acceptance, and Tom Lawand et al, Brace Research Institute at McGill U., Canada, tested steam cookers in several developing countries, but in these areas, too, there were still lower-cost alternatives for households. (Halacy, p. 4). >
1955– The International Solar Energy Society began as the Association for Applied Solar Energy, whose first conference in Phoenix, AZ, USA, included many practical solar cookers. By then the technical basics of solar cooking were known. Exhibited solar cookers included parabolics by J.L. Ghai of India, Georg O.G. Löf (US), Adnan Tarcici (Lebanon) and S. Goto (Japan) and box cookers by Maria Telkes (US) and Freddy Ba Hli (Burma)
1959– The U. N. Food and Agriculture Organization (FAO) measured water-heating capacities of a parabolic cooker and an oven type cooker (Löf, 1963, p. 132).
1960s- The U.N. tried a few pilot projects with a variety of elaborate devices designed by engineers with little or no attention to consumer needs, then blamed ‘resistance to change’ for lack of immediate intensive use.
1961- A United Nations Conference on New Sources of Energy included many solar cooker pioneers, including Telkes, Löf, Duffie, Pruta and Abu-Hussein.
1970s– Spreading deforestation prompted research and promotion of solar cooking by governments of China and India. A petroleum shortage temporarily created new interest in renewable energy worldwide.
1973– Barbara Kerr, USA, built many types of concentrator and box type solar cookers from descriptions, including Ghosh’s box cooker in India. She used simplest materials inspired by retained heat cookers (‘hay boxes’) and developed low-cost, simple solar cookers using recycled materials and aluminum foil. She worked with Bob Larson through People united for Self-Help to share these simple solar tools with homeless and low-income neighborhoods.
1976– Kerr and her neighbor, Sherry Cole, cooked 2 meals per day for 40 people for two weeks for a women’s conference. Kerr, an RN with a Masters in social work also did extensive pioneer work on solar food dryers, sanitizers and sterilizers and through-the-wall solar cookers.
1978– Kerr and Cole began small-scale production and promotion of cookers and plans for people to make their own. Prof. Bob Metcalf learned about Kerr-Cole cookers through Fred Barrett, USDA, bought one, and immediately became a regular user and began research on their germ-killing capacities. He quickly became a promoter of solar cookers both in the Sacramento area and beyond, teaching many in Sacramento including Thais Thomas who in turn taught Clark and Eleanor Shimeall (who wrote a still-popular cookbook). Bob Larson was giving workshops on building solar water heaters.
And in 1979– The Organization of African Unity held the 1st of 7 sessions on New, Renewable and Solar Energies. The most recent was in 2000 in Dar es Salaam, Tanzania. Dr. Metcalf, with student Marshall Longvin documented water pasteurization in solar box cookers.