Showing papers on "Renewable energy published in 1981"

Solar energy handbook

Abstract: Solar energy handbook , Solar energy handbook , کتابخانه دیجیتالی دانشگاه علوم پزشکی و خدمات درمانی شهید بهشتی

Biomass Conversion Processes for Energy and Fuels

Abstract: The book treats biomass sources, promising processes for the conversion of biomass into energy and fuels, and the technical and economic considerations in biomass conversion. Sources of biomass examined include crop residues and municipal, animal and industrial wastes, agricultural and forestry residues, aquatic biomass, marine biomass and silvicultural energy farms. Processes for biomass energy and fuel conversion by direct combustion (the Andco-Torrax system), thermochemical conversion (flash pyrolysis, carboxylolysis, pyrolysis, Purox process, gasification and syngas recycling) and biochemical conversion (anaerobic digestion, methanogenesis and ethanol fermentation) are discussed, and mass and energy balances are presented for each system.

Biomass energy from crop and forest residues

Abstract: Residues remaining after the harvest of crop and forestry products are being proposed as a substantial energy source for the nation. An estimated 22 percent of the residues might be utilized, providing a renewable source of high-grade energy with the potential of supplying 1 percent of the current U.S. gasoline consumption as ethanol or 4 percent of the total electrical energy used. These net energy benefits are limited by high energy costs to collect, transport, and process the residues. Environmental threats include soil erosion, water runoff, and nutrient loss.

Predicting reactor biomass concentration in a fluidized-bed system

Abstract: A new fluidized-bed process for wastewater treatment is an adaptation of the fixed-film biological reactor. As part of a development and demonstration program, a number of pilot plants and treatibility units have been designed and built for operation in the U.S., Canada, and other countries. The principal advantage of the fluidized-bed process is a reduction in reactor size caused by the development of high concentrations of biomass. By development of a hydraulic model for the fluidized-bed reactor on the basis of the principles of liquid-solid fluidization, a theoretical value for the reactor biomass concentration may be determined. A design basis for the system may then be formulated by combining the hydraulic model with a model for the biofilm kinetics. This paper presents information on the development of a hydraulic model for the system and reports on the results of applying the model to predict the biomass concentration observed during operation of two of the pilot plants. One of the pilot plants is a 0.37-m/sup 2/ (4-sq ft) rectangular fluidized-bed reactor 4.4m (14.5 ft) high, which is located in Cedar Rapids, Iowa, treating high-strength carbohydrate wastewater. The other pilot is a 2.22-m/sup 2/ (24-sq ft) rectangular reactor 4.4m (14.5 ft) high,more » which is located in Orillia, Ontario, Canada, treating primary municipal wastewater.« less

Renewable Energy Sources and Rural Development in Developing Countries

Abstract: Economic and geopolitical constraints on global nonrenewable energy supplies will force many nations, especially the developing countries, to accelerate their use of local renewable energy sources. This paper discusses some of the technical, economic, and socioeconomic aspects of the application of renewable (solar) energy sources for rural development in resource-poor population-rich developing countries. The possible role of educational institutions in the U.S. and in the developing countries in assisting in the successful introduction of solar technologies in rural areas is outlined. A selected bibliography is included for the benefit of readers interested in additional information on this important topic.

Electrolytic Production of Hydrogen

Abstract: In order to meet the anticipated enhanced demands for hydrogen as a chemical feedstock, as a process gas, and as a clean fuel, the development of techniques for bulk hydrogen generation from nonfossil primary energy sources is vital. With the continued increase in costs and dwindling availability of natural gas and oil, which are the major sources of hydrogen in most countries, the production of hydrogen from coal, or by water electrolysis using electricity derived from hydroelectric, nuclear, solar, geothermal, or fusion energy, will become quite attractive in the near future. Since the energy crisis of 1973, methods have been actively pursued for the production of electricity and/or heat (forms of energy which are not easily storable or transportable over long distances) from renewable sources. Even if such methods are found, there will still be a need for portable fluid fuels which will have to be manufactured on a large scale from the above-mentioned resources. Portable fuels will be most essential for transportation applications. Hydrogen, methanol, or ethanol are the most likely candidates for fluid fuels. Water electrolysis is the only proven technology for production of hydrogen from nonfossil fuel primary energy sources. Other methods such as thermochemical, photochemical, or biochemical are in the infant research stage and from an engineering and economic standpoint show little prospects of success for production of hydrogen on a commerical scale. Due to the intermittent nature of some of the renewable energy sources (solar, wind), energy storage in some other form becomes essential. Here again, electrolytic production of hydrogen is most attractive. H2 is ideal, whereas methanol or ethanol will be an alternative fuel for future transportation applications. In the nuclear, solar, or fusion era, the most convenient method of methanol production will be by the gas phase catalytic reaction of CO2 (from carbonate rocks, the atmosphere, or the ocean) and electrolytic hydrogen. Ethanol can be easily manufactured from any form of biomass.

Wind Energy - A Utility Perspective

Abstract: Of all the renewable energy systems, wind turbine generators (WTG's) are likely to make the earliest significant cost-effective' contribution to the utility grid. In order to accelerate the commercial deployment of WTG's, several issues must be addressed in a timely manner. This paper presents some of the ' issues facing the utility industry as they relate to implementation of an effective wind energy program. In addition, the Southern California Edison Company's wind energy program is presented, which is designed to provide pertinent answers to the technical, economic and environmental issues concerning WTG installations and their commercial viability as a future generation resource

The Economic Feasibility of Crop Residues as Auxiliary Fuel in Coal-Fired Power Plants

Abstract: Rising fossil fuel costs spark interest in crop residues as a renewable energy source. Residue costs for combustion in power plants are estimated in 1975 prices to evaluate their feasibility. Costs are estimated for farm production, transportation, and processing and handling at the energy-recovery level. They are incorporated into an Iowa agricultural programming model, which includes an electric utility sector. The model, including crop production, is solved for several scenarios - a base solution, energy price increases, and a sulfur constraint. Under these scenarios, crop residue replaces coal at 20%, 40%, and 60% of the 1975 Btu's consumed.

Long-term energy resources

Abstract: Papers presented at this conference cover some 45 different energy sources as well as the energy policies and issues of a number of countries, both developed and developing. The papers are grouped into sections dealing with a world energy overview, energy policy and planning, coal, petroleum, shale oil, tar sands, heavy oil, enhanced oil recovery, unconventional natural gas, solar energy, energy from biomass, water power, wind energy, geothermal energy, nuclear energy, conservation and mechanical energy. The final section contains 28 national energy reviews. 26 papers have been abstracted separately.

Anaerobic Digestion of Kelp

Abstract: The search for new sources of energy is intensifying as the demand for energy increases and supplies of fossil fuels are becoming depleted. One possible long-term solution to this dilemma is the conversion of renewable sources of organic matter, such as wastes and biomass, to products that are suitable for use as fuels. Although organic wastes represent a minor potential supplemental energy resource,(1,2) land- and water-based biomass could be developed into major resources.(1,3-–5) This has led to the concept of land- and water-based energy farms directed at production of biomass for conversion to synthetic fuels. Development of energy farms in the marine environment seems particularly attractive because large areas are available. In fact, it is generally thought that seaweed farms could be used both for energy production and to promote growth of fish and other marine fauna.

Biomass Energy Systems and the Environment

Abstract: The technology, resources, applied, and experimental features of biomass energy resources are explored, with an emphasis on environmental and social implications of large-scale biomass development. The existing land and water based biomass resource is described in terms of available energy, ecological concerns, agricultural crops, livestock production, freshwater systems, and ocean systems. Attention is given to proposed systems of biomass energy production from forestry and silviculture, agricultural crops, livestock wastes, and freshwater and ocean systems. A survey is made of various biomass materials, techniques for conversion to gas, liquid fuels, or for direct combustion, and impacts of large-scale biomass production and harvest are examined. Particular note is made of the effects of scaling biomass conversion systems, including near- and long-term applications, and ethics and aesthetic concerns.

Planning solar neighborhoods

Abstract: Planning Solar Neighborhoods is a comprehensive manual for planning energy conserving residential developments in California. Due to the state's great climatic diversity, six climate regions are defined and key building, planning, and landscape planting guidelines are presented for each. A well illustrated chapter on solar building concepts includes a series of performance simulations of modifications to a standard house located in each of the state's climate regions. The heart of the manual describes solar and energy conservation options for neighborhood design including siting the development; relationships between street orientation, lot and building design; and the importance of flexible setback standards. Presentations on various types of high density housing and circulation planning techniques are given. The landscape planting chapter describes fundamental vegetation planning concepts, concentrating on species-specific tree selection and location techniques to maximize solar access and appropriate summer shading. The manual's most technical sections describe solar access planning fundamentals, design with shadows, working with difficult topography, and achieving solar access at high densities. Two summary chapters, Examples and Local Implementation, present an overview of whole neighborhoods designed for energy conservation, and the role of local governmen in promoting solar developments including subdivision review procedures.

Fuel ethanol from biomass: production, economics and energy

Abstract: A review and discussion of the raw materials and recent modifications in EtOH manufacture as well as the economic and energy issues involved (Refs 55)

Producer gas engines in villages of less-developed countries.

Abstract: Producer gas engines could have an important role in the decentralized production of mechanical energy in rural areas of less-developed countries. With this technology mechanical energy is produced from solid fuels by use of internal combustion engines. A comparison with other renewable energy options, on the common basis of energy efficiency and economics, shows that producer gas engines may have significant advantages and deserve serious attention.

Analysis of federal incentives used to stimulate energy consumption

Abstract: Conclusions of an analysis which identifies and quantifies Federal incentives that have increased the consumption of coal, oil, natural gas, and electricity are summarized. Data on estimated cost of incentives used to stimulate energy consumption by incentive type and energy source are tabulated for coal, oil, gas, and electricity. It is suggested that the examination of past incentives can be useful in developing guidelines and limits for the use of incentives to stimulate consumption of solar energy. (MCW)

Renewable sources of energy and the environment

Abstract: Renewable energy sources, just as all other sources of energy, have an impact on the environment on a local, national, and international scale. This book examines the effects on human life and the ecosystem, on water and air quality, and on land use of developing and using these resources. The purpose is to highlight the relative impacts and motivate efforts to solve potential problems. Eight chapters, each by a different author, cover: (1) the promise of renewable sources of energy; (2) geothermal energy; (3) solar energy; (4) wind energy; (5) energy from the sea; (6) hydroelectric energy; (7) energy-storage systems; and (8) energy from biomass. 344 references, 54 figures, 37 tables. (DCK)

Behavior of the concrete dam of the Ust-Ilim hydroelectric station under operating conditions

Abstract: 1. The concrete dam of the Ust-Ilim hydroelectric station after 3-yr operation under design conditions is in a satisfactory state. The seasonally opening joints in three powerhouse sections worsen the static behavior of these sections and the seepage through them presents difficulties during operation. 2. The actual strength of the concrete of the dam is unjustifiably high, and for blocks of the interior region the impermeability is thrice greater than the concrete grade impermeability. The superfluous strength of the concrete is due to the high content of cement. 3. The state of stress of the dam and its contact zone is more favorable than according to the results of current static calculations. This is explained mainly by the technological depression of the upstream face and low uplift pressure. 4. The offset profile of the powerhouse sections should be calculated not only for the load of the hydrostatic pressure of the water of the upper pool but also for the temperature effects of the period of filling the reservoir.

New and renewable sources of energy

Abstract: An overview of the work done on new and renewable sources of energy in India is presented and the growth of an energy scenario and the existence of energy-related foreign exchange deficits are discussed. The available energy stock of India has to be proven at an accelerated pace and new sources of energy must be exploited immediately. Various means available to convert solar energy and the respective technologies and devices are discussed and the organizations involved in exploiting these technologies are pointed out. The discussion includes wind energy, hydro-power, ocean power, biomass sources, geothermal energy, oil shale and tar sands, and animal power.

Projected Costs for Electricity and Products from OTEC Facilities and Plantships

Abstract: The vast ocean thermal resource of the tropics can be used to serve all areas of the U.S. through the production at sea of fuels or energy-intensive products that can be transported to market by ship. This paper addresses ammonia, liquid hydrogen, methanol, and liquid methane, which could be sold as fuels or chemicals or used as hydrogen sources for onshore fuel-cell power systems. Estimated costs of their production on 325-MWe ocean thermal energy conversion (OTEC) plantships and their delivery to U.S. ports and inland cites are presented. The most promising product is ammonia, first for use in fertilizers and the chemical industry, and later as the least costly carrier of hydrogen for use in fuel cells. Estimated costs of delivering OTEC electricity by undersea cables from moored offshore plants to U.S. islands and Gulf Coast states are compared with costs of electricity from OTEC ammonia and from coal and nuclear power. Commercial viability for both OTEC approaches by the 1990-1993 period is indicated. The potentials for private cost-sharing in the initial 40-MWe demonstration facilities and plantships also are discussed.

Agricultural residues: renewable energy for utility power companies.

Abstract: MUCH attention is currently focused on the use of biomass as fuel. Most research is concerned with the conversion of biomass into useful energy forms: li-quids, gases, high density solids, process steam, or elec-tricity. However, the identification of expected collection and transportation costs for biomass is necessary before biomass can be conceived of as fuel. This paper presents the results of one of the first attempts to quantify the pro-cesses that must occur prior to the conversion of distrib-uted biomass resources such as agricultural and forest residues. Specifically, the results presented here of a pre-liminary feasibility study undertaken for a major Califor-nia combined gas and electric utility company indicate that distributed biomass resources can be collected, pro-cessed, stored, transported, and delivered to locally sited conversion facilities at costs competitive with other fuels. While research was performed using California data, the results are common to most of the biomass produced in the United States.

Agricultural policies and biomass fuels

Abstract: The agricultural sector has been a large and growing consumer of energy over the last 30 years. The energy consumed in this sector for production of food and fiber is largely derived from nonrenewable resources of pe­ troleum and natural gas. 1 Concern over dwindling domestic reserves of petroleum and rising energy prices have focused attention on the possible impacts of these energy intensive practices upon food prices and the security of food supplies. Some analysts have recommended increasing the energy efficiency of agriculture to lessen the sensitivity of food prices to energy costs. This would involve maintaining current levels of production while simultaneously reducing the energy consumed. Other analysts have recom­ mended increasing production of biomass feedstock per acre in order to make agriculture a source of renewable energy. To the extent that produc­ tion of biomass feedstock requires energy consumption, an apparent conflict

Energy for the developing world: The [new wisdoms] are wrong

Abstract: A rapidly building concensus, in the rich developed nations, is that less develped countries (LDC) should support large, costly, programmes of rapidly developing non-oil renewable energy sources, and energy conservation. However, oil use in the LDCs is tiny in relation to that of rich nations, even if growing faster. On a per capita base the difference is greater still. Thus conservation, as a solution to short run oil supply problems (e.g. OPEC output ceilings) is a responsibility of the nation grouping that uses and wastes most oil. Small percentage cuts by the OECD-IEA group could provide ample supplies for the growing needs of LDCs without driving prices inevitably higher. For LDCs there are now many devices for controlling or reducing their foreign exhange spending on oil per unit import. Accelerated oil search and devlopment provides the best midterm opportunities for solving oil supply problems in LDCs especially if OPEC and rich nation loan funding and technical support are accelerated. the impetus for the necessarily costly rapid development of unconventional energy sources must and should come from the rich nation in the short and midterm, for aid-assisted transfer to LDSs in the longer term. This will allow the scarce capital of LDCs to be utilized for non-energy sectors where needs are immediate and cirticial, and for oil search and development.

Power/energy: A solar-pond power plant: Israel reviews an experiment which got under way more then a year ago: Will it prove a model for more like it?

Abstract: After more than a quarter century of research, Israel has built a 7500-m2 salt pond and turned it into an electric power plant. The experimental 150-kW installation, which began operating in December 1979 in Ein Bokek, near the Dead Sea, collects and stores solar energy in water in which the salt concentration increases with depth. A low-temperature turbogenerator converts the thermal energy into electricity.

Linear down-draft biomass gasifier

Abstract: A biomass gasification method and apparatus employs a rectangular design and linear injection of feedstock to allow compact modular design to accommodate a wide variety of energy demands with a single-size production unit which can be stacked with others for different energy output demands The method and construction make use of a long and narrow grate in combination with an air supply system and producer gas return system which uses a down-draft technique to restrict and control by-products and to improve the efficiency of the energy conversion system