|GATE - 1/93 - Solid Waste Management (GTZ GATE, 1993, 52 p.)|
CPP Wood - firing circular kiln
Therefore, there is the possibility (in optimum conditions) of using 30 % less fuelwood, plus having up to 30 % less breakage.
The CPP kiln is a ring of common bricks, mortared with a mixture of clay and rice husk. It should be constructed on a well drained area, and protected from rain by a roof. The floor is covered with a layer of bricks, which may be broken pieces.
Four fireboxes are provided, spaced equally on the perimeter of the kiln. These lead to a cross shaped channel system, made from 2 rows of common brick, spaced about 7 inches apart and bridged over with standard 9 inch bricks.
The kiln can be as big as 3 meters in diameter and about I meter high. Larger sizes are difficult to cover with clay plaster. Smaller kilns can be made according to firing requirements. Sizes 1 meter and less in diameter work well with one firebox running across the diameter.
The $ 38.46 cost is for bricks and mortar for a 3 meter diameter kiln. Labor and the firing house are provided by the potters. The firing house is usually a thatched roof over a bamboo frame, which has certain fire risks. In Nepal, the kilns are located outside the village, or if in more congested areas, are built in fireproof enclosures.
James Danish/Diwakar Pradhan
New Energy Strategy Needed
Washington - The developing countries' current energy path is driving them more deeply into debt and worsening the quality of life for millions, according to a study by the Worldwatch Institute. Economic development will be increasingly elusive without extensive reforms that encourage investment in greater energy efficiency.
"Plans for massive expansion of conventional energy use are projected to cost more than $ 4 trillion over the next thirty-five years - triple the current Third World debt of $ 1.35 trillion, according to Worldwatch paper 111.
Empowering Development: The New Energy Equation. Author Nicholas Lenssen proposes a new strategy: "By investing in more efficient factories, appliances, and transportation, and in new energy supplies, developing nations can save hundreds of billions of dollars, reduce pollution, and make their economies more competitive."
"Each $1 invested in improving energy efficiency leads to average savings of $ 5 in energy supply," the study finds. Such efficiency savings would free up money desperately needed for education, health care, and water treatment plants. New supply sources natural gas and renewable energy technologies - are also key to a new energy strategy. Photovoltaics are now the least expensive way to supply electricity in many rural areas.
Since 1960, developing countries have more than quadrupled their energy use. In sub-Saharan Africa, nearly a third of hard currency earnings are spent on petroleum imports. One fourth of Third World government debt payments in the eighties went to finance energy projects.
"By emphasizing energy services, rather than simply increasing supplies of oil, coal, or electricity, developing countries can help solve the economic and environmental problems in the energy sector, and revitalize stalled development efforts throughout much of the world", says Lenssen.
Over 35 years, $ 350 billion invested in efficiency improvements could eliminate the need for $ 1.75 trillion worth of power plants, oil refineries, and other energy infrastructure.
The techniques are already available and in use. In 1980, China launched an ambitious efficiency program to improve energy use in major industries. "Efficiency gains were found to be one third less expensive than comparable investments in coal supplies" says Lenssen. "Had the nation failed to make such progress, energy consumption in 1990 would have been 50 percent higher than it actually was."
In Brazil, the National Electricity Conservation Program invested $ 20 million in improving efficiency. That relatively small investment reduced the nation's need for new power plants and transmission lines by roughly $1 billion in the late eighties.
But even with massive improvements in efficiency, increased energy supplies will still be needed. The report outlines some of the available alternatives to costly oil and polluting coal: Some 50 developing countries possess extensive, unexploited stores of natural gas. In some countries, natural gas is considered a waste product of petroleum production and flared into the open air.
In Nigeria, the 21 billion cubic meters of gas flared in 1990 could have furnished enough energy to meet all the country's current commercial energy use - plus those of neighboring Benin, Cameroon, Ghana, Niger and Togo.
Solar and wind energy: During the past decade, the cost of solar and wind electricity systems have fallen 66 - 90 percent; they are emerging as the least expensive route to electricity in some developing countries. Already, more than 60,000 households in developing nations have installed photovoltaic lighting units. Biomass resources also have enormous potential.
If sugar mills burned all their residues using advanced gas turbine technology - now being commercialized in Brazil - they would meet more than a third of the total current electricity use in developing countries.
Opportunities for the Third World
Bonn - The Federal Ministry for Economic Cooperation (BMZ) and the Federal Ministry for Research and Technology (BMFT) have expressed support for increased use of renewable energy sources. In a joint statement issued in December 1992, the two ministries stress that effective use could be made of renewable, decentralized sources of energy such as solar, wind and water power and biomass, above all in rural regions.
The statement goes on to point out that 55 % of the world's population have no access to any central energy supply and depend on the "fuel of the poor", i.e. wood and charcoal. But in recent years, according to the statment, the developing countries have recognized that renewable forms of energy offer a "not inconsiderable" chance of improving
The quality of life and the environment of their rural populations.
However, renewable energy must be offered at affordable prices, and the statement lists certain advances in this area. In the past 10 to 15 years, for example, the costs of photovoltaic systems have been reduced tenfold. Since the mid-1970s, the BMZ has provided DM 450 million for the promotion and dissemination of appropriate, environmentally compatible and decentralized technologies.
Solar energy accounted for 55 %, wind energy for 5 %, biomass for 25%, and mini- and micro-hydropower for 15%. The Ministry has approved aid of DM 2.4 billion under Financial Cooperation, notably for larger hydropower plants and other renewable forms of energy. About DM 660 million flowed from BMFT funds into development aid projects involving German industry.