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  1. 1986-01-01 Hot water is not always necessary, and in warm climates it may be relatively easy to do without. It is, however, more effective than cold water for many purposes. Even so, in some areas hot water is not used because fuel is so expensive it is used only for essential tasks. A solar heater can...
  2. 1986-01-01 The easiest and most practical application of solar energy is for heating water. It has been technically feasible to heat household water using solar energy since the 1930's. Solar water heaters for homes and industry have been employed extensively in Israel, Australia, and Japan, and were quite...
  3. 1980-01-01 A solar still is a device that uses energy from the sun to purify salt- or brackish water. Solar stills (as shown in Figure 1) can be easy to construct and maintain. Depending upon their size, they can provide water for many uses. And in desert areas where sunshine is plentiful and water is not,...
  4. 1985-01-01 This paper examines water pumping systems that use solar radiation as a direct source of energy. We look primarily at small-scale rural applications in the Third World, where the potential benefits are greatest and the near-term economics seem most favorable. Two generic technical approaches for...
  5. 1985-01-01 In many equatorial regions, native trees and bushes are being cut at an alarming rate to meet the growing demands for agricultural land, industry, and fuelwood and charcoal. The environmental consequences of this deforestation are severe, ranging from soil erosion and climate changes to flooding...
  6. 1967-01-01 The VITA Solar Cooker was especially designed to be sturdy, relatively easy to make, easy to repair, and low in cost. It uses the principle of the Fresnel reflector which concentrates light and heat by using several simple reflecting surfaces. Most other cookers use a doubly-curved reflecting...
  7. 1986-01-01 The use of waste wood is as old as humankind. Stone-age people probably used wood waste to fuel fire since greenwood is very difficult to burn. Manufacture of items from wood also began very early. Wood was used for tools and weapons and, no doubt, cut-offs from the production of long implements...
  8. 1986-01-01 This paper describes a number of uses of wood wastes as fuel, which is how the greatest proportion of wood wastes are used. Non-fuel uses of wood wastes, for example in building materials, industry, and agriculture, are described in another paper, "Understanding the Non-fuel Uses of Wood Wastes."...
  9. 1984-01-01 This paper describes the production and use of ethanol (ethyl alcohol) as a liquid fuel. The production of ethanol is a well-established technology; however, the use of ethanol as a liquid fuel is a complex subject.
  10. 1990-01-01 The sheep was one of the earliest animal species to be domesticated, with evidence that they were kept and not hunted as early as 10,700 years ago in the gorge of the Greater Zab River in Northern Iraq. Wool has been found in the remains of 20,000-year old villages in Switzerland (Blakely and...