VITA - Volunteers in Technical Assistance
This is a series published in the 1980s by Volunteers in Technical Assistance to provide an introduction to specific state-of-the-art technologies of interest to people in developing countries. The papers are intended to be used as guidelines to help people choose technologies that are suitable to their situations. They are not intended to provide construction or implementation details. People are urged to contact a knowledgeable organization for further information and technical assistance if they find that a particular technology seems to meet their needs.
The papers in the series were written, reviewed, and illustrated almost entirely by VITA Volunteer technical experts on a purely voluntary basis. Some 500 volunteers were involved in the production of the first 100 titles issued, contributing approximately 5,000 hours of their time. VITA staff included Leslie Gottschalk and Maria Giannuzzi as editors, Julie Berman handling typesetting and layout, and Margaret Crouch as project manager.
Permission has been granted by the current holder of Intellectual Property Rights for VITA content, Relief International, to publish the VITA library on ECHOcommunity.
Please note that re-release of these documents is a work in progress where we are recovering images and tables from archival documents.
127 Các Số trong Ấn phẩm này (Hiển thị vấn đề 151 - 140) Trước | Tiếp theo
Double-Drum Sawdust Stove - 01-01-1988
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In the United States, sawdust traditionally has been burned in large furnaces for industrial heating, in smaller furnaces for home heating, and in fireplaces in the form of compressed logs. In other parts of the world, loose sawdust has been burned for years in inexpensive double-drum stoves. These stoves are well suited for heating cabins or workshop areas.
The double-drum sawdust stove has other advantages. It is inexpensive to fabricate; it uses recycled components; it burns inexpensive fuel; and it heats a long time with minimum tending.
Portable Metallic Cookstove - 01-01-1988
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This Industry Profile is one of a series briefly describing small or medium-sized industries. The Profiles provide basic information for starting manufacturing plants in developing nations. Specifically, they provide general plant descriptions, financial, and technical factors for their operation, and sources of information and expertise. The series is intended to be useful in determining whether the industries described warrant further inquiry either to rule out or to decide upon investment. The underlying assumption of these Profiles is that the individual making use of them already has some knowledge and experience in industry development.
Dollar values are listed only for machinery and equipment costs, and are primarily based on equipment in the United States. The price does not include shipping costs or import-export taxes, which must be considered and will vary greatly from country to country. No other investment costs are included (such as land value, building rental, labor, etc.) as those prices also vary. These items are mentioned to provide the investor with a general checklist of considerations for setting up a business.
Cookers And Stoves: FIRELESS COOKER - 01-01-1985
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Where fuel is scarce, this easy-to-build fireless cooker can be a contribution to better cooking. It keeps food cooking with a small amount of heat stored in hot stones; loss of heat is prevented by a thick layer of insulating material around the pot.
Fireless cookers have been successfully used in many countries. Once the principle of operation, heat retention through insulation, is understood, the reader may develop plans that are better suited to local resources than those described here. In some countries, fireless cookers are built into the ground. In others, they are built from surplus tin cans, one can fitted into another tin can or box but separated by paper, sawdust, or other layers of insulation.
Testing The Efficiency Of Wood-Burning Cookstoves - 01-01-1985
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This document includes the step by step procedures for each of the standardized tests, followed by Procedural Notes that give specific suggestions for conducting the tests. The sample data and reporting forms included for each test are designed to simplify the recording of essential information. For easy reference, Technical Notes giving background information relevant to all three tests are printed on colored paper. A glossary and list of abbreviations are followed by a section discussing concepts of efficiency used in testing stoves.
Improved Woodstoves: Users' Needs And Expectations In Upper Volta - 01-01-1980
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These three improved stove construction and dissemination projects are augmented by two research projects. One concerns technical and scientific research to formulate mathematical rules for the construction of fuel efficient stoves. It is being conducted by the University of Eindhoven and the TNO Research Institute, with financing from the Dutch Government. The studies envisioned will be carried out in Dutch laboratories and in the Sahelian countries, in close collaboration with national institutions for scientific research. The other research project involves both a technical study of energy and materials available in Sahelian countries, and a sociological study of food habits and cooking practices of the Sahelian people.
The following report presents the results of a sociological study undertaken by VITA,(6) and funded by IBM, with the participation of people from the Ministries of Social Affairs and Women; Rural Development; Environment and Tourism; the Women's Technical Training section of the AVV (Volta Valley Management); and, the Federation of Voltaic Women.
We would like to pay tribute to the people responsible in those ministries and organizations especially to the Minister of Social Affairs and Women, whose moral and material support was a decisive element in carrying out the study. The continued interest and effective participation of the staff and field workers who often worked overtime, demonstrated their deep interest in a technology which helps families and women meet a basic need. To all of them, we express our gratitude for this first collective work which, we hope, will lead to the concrete results the population awaits.
Solar Water Heater - 01-01-1986
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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 supply needed hot water without using up available fuel.
Solar water heaters represent one of the easiest, most practical applications of solar energy on an individual and small-scale basis.
Understanding Solar Water Heaters - 01-01-1986
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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 popular in Florida and California prior, to World War II.
A solar water heater consists of a solar collector, a storage tank, and, in most cases, a system of pipes to transfer water between them. The solar collector is to the solar heater what a boiler is to a conventional heater: it heats the water or fluid. Depending on the technology used, solar water heating systems can make use of pumps or natural circulation and can use water or other fluids to conduct heat.
Solar Still - 01-01-1980
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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, a solar still can be very important.
A solar still is little more than a shallow, watertight box with a clear glass or plastic top. The bottom of the box is usually painted black to absorb the sun's heat. The base of the still is filled with nonpotable water, for example, brackish water. The sun's heat evaporates the water, which then condenses on the inner surface of the cover. The condensed water runs into troughs from which it can be collected in storage containers. The still's cover is tilted to collect the greatest amount of solar energy. Glass-covered solar stills are much more rugged and trouble-free and are able to withstand climatic and environmental conditions much better than plastic. So, over a long period of time, the increased cost of glass will pay for itself.
Understanding Solar Stills - 01-01-1985
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Solar distillation uses the heat of the sun directly in a simple piece of equipment to purify water. The equipment, commonly called a solar still, consists primarily of a shallow basin with a transparent glass cover. The sun heats the water in the basin, causing evaporation. Moisture rises, condenses on the cover and runs down into a collection trough, leaving behind the salts, minerals, and most other impurities, including germs.
Although it can be rather expensive to build a solar still that is both effective and long-lasting, it can produce purified water at a reasonable cost if it is built, operated, and maintained properly.
This paper focuses mainly on small-scale basin-type solar stills as suppliers of potable water for families and other small users. Of all the solar still designs developed thus far, the basin-type continues to be the most economical.
Understanding Solar Water Pumps - 01-01-1985
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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 solar water pumping systems will be examined: (1) thermodynamic (in which the radiant energy is first converted to heat); and (2) photovoltaic (in which it is first converted to electricity). Since photovoltaic technology is more mature, it is used for economic comparisons with other methods of pumping water. Our treatment of this complex subject is necessarily cursory; the aim is to provide prospective users with sufficient insight to determine whether solar water pumping is a plausible option for their specific situation, and to furnish a guide for further investigation.