Showing papers on "Renewable energy published in 1979"

Progress in biomass conversion

Abstract: This book reviews the long-range potential of biomass. It also discusses how biomass could replace petroleum and natural gas through different processes and under different circumstances, and at what price and to what extent. It provides a comparison with alternative resources, including coal and petroleum, and taking into consideration such problems as corrosion and erosion....These papers provide a demonstration of how technical feasibility can be distinct from economic viability and how changes in one can affect the other. The contents discussed are: Hydroprocessing of Biomass Tars for Liquid Engine Fuels; Fuel Characteristics of Wood and Nonwood Biomass Fuels; Factors Influencing Dilute Sulfuric Acid Prehydrolysis of Southern Red Oak Wood; The Energy Costs of Increased Organics Recovery for Chemical By-Products in Kraft Pulp Mills; Microeconomic Approaches to Biomass Fuel Pricing; Fuel Characteristics of Selected Species of Beached Logs in Southeastern Alaska; An assessment of the Costs and Benefits of Recovering Logging Residue for Energy Use; Review of Biomass Gasification Technology; and Index.

Energy future: Report of the energy project at the Harvard Business School

Abstract: This, the third edition of the Harvard Business School project report continues the theme of a balanced energy system to replace dependence on imported oil. The revision incorporates new material in response to shifts in energy relationships and changes in energy assumptions. The chapters cover the shift from easy oil production to a future of uncertainty and hostility; the status of natural gas, coal, and nuclear energy sources; the key energy source available from conservation; the importance of giving solar energy an economic chance; the need to remove the adversarial approach to energy policy; and a challenge for a balanced policy to guide an economically sound and politically acceptable transition. An appendix examines the limits to econometric modeling. 490 references, 4 figures, 21 tables. (DCK)

Petroleum Plantations for Fuel and Materials

Abstract: The possibility for the development of an economically useful solar energy and materials system is an outgrowth of, and in a sense, a return to, an older system. The best existing solar energy-capturing device known, the green plant can be used by selecting and modifying it to produce the materials wanted, namely, hydrocarbons of suitable molecular weight and structure. The choice of plant(s) will depend on growth rates and habits, hydrocarbon productivity and harvest adaptability, as well as process development. Experiments have indicated the economic feasibility of the production of oil from hydrocarbon-producing plants, particularly species of Euphorbia and Asclepias. With the continued increase in cost of petroleum from fossilized photosynthetic residues and the continued decrease of its availability, the development of this alternate energy source becomes absolutely necessary. 11 figures, 2 tables.

Utilization of solar energy

Abstract: Solar energy is utilized to convert water into steam for use in driving a turbine which, in turn, is used to generate electricity. At the same time air in a solar panel is utilized to drive another turbine which in turn generates electricity. The water recovered by condensation of the steam is permitted to drop from the elevation at which it is accumulated and that water is used to drive another turbine which in turn generates further electricity.

Complimentary nature of wind and solar energy at a continental mid‐latitude station

Abstract: Daily values of solar and wind energy have been used (i) to study renewable energy availability at various times of year, (ii) to test the level of persistence for inferences about the practicality of energy storage and (iii) to examine the complementary behaviour of these two daily time series on both seasonal and daily bases. Results for the station studied (central Iowa) show a bimodal distribution for winter solar energy, whereas non-winter solar and wind (all seasons) show unimodal distributions. Wind and solar energy were observed to be highly complementary on an annual basis, but only slightly complementary on a daily basis.

Total energy analysis of Gotland's agriculture: A northern temperate zone case study

Abstract: This paper presents a study of a modern agricultural system in a northern region, namely, the island of Gotland, Sweden. Primary emphasis is placed on the energy costs of agriculture and the energy flow within the system. In addition, some attempt is made at assessing environmental costs of declining water quality. For the purpose of perspective some comparisons are made to Israeli agriculture and selected crops in the United States and Great Britain. Historical analysis of Gotland's agriculture indicated the energy provided by horses to be 1 10 in 1972 as compared to 1945 while the fuel consumption of tractors increased 50% from 1954 to 1974. The energy value of the harvest increased ca. 1.5 to 2 times its value in 1947. Direct energy costs include 223 TJ of fuels and 51.9 TJ of electricity. Indirect energy costs include 103 TJ for goods and services, 327 TJ for capital, 465 TJ for the production of fertilizer, 17.6 TJ for the production and transport of grain and 71.2 TJ for the energy cost of feed. The final output of animal and vegetable matter was 1670 TJ. One unit of food energy output required 0.84 units of direct and indirect energy in oil equivalents. Calculations indicate that Gotland's agriculture is more energy costly than selected U.S. crops but at least half as costly as Israeli agriculture. Expressed in energy terms, each year 3240 PJ of renewable solar energy on Gotland's agroecosystem is coupled with 1.3 PJ of fuel and electrical energy to produce 1.7 PJ of edible animal and vegetable products.

Energy Flows in the Developing World

Abstract: Out of sheer necessity, the developing countries rely almost entirely on renewable energy forms such as wood and biogas; unfortunately, many of the same countries may be pursuing developmental strategies that increase their dependence on natural gas and other scarce fossil fuels, according to Canada's University of Manitoba. Detailed studies of energy use in developing countries are becoming more frequent, but proper long-range choices that balance traditional solar and modern fossil-fuel energetics depend on thorough analysis of the existing and potential energy flows.

Energy-storage systems

Abstract: The opportunities for energy storage in electric power systems, storage applications in transportation, and energy-storage applications in commercial and residential structures are discussed. Then, energy storage as it might apply to solar energy systems, ranging in scale from home-size to electric-utility power grids, is discussed. Energy reservoirs consisting of pumped water, compressed air, batteries, and ways of storing heat and cold can do much to help coal, nuclear, and solar energy replace substantial quantities of oil. (MCW)

Ethanolic fuels from renewable resources in the solar age

Abstract: This communication describes how ethanol, other liquid fuels, and organic chemicals can be produced from cellulosic biomass at prices that can compete with those of petroleum derived materials by employing presently available or soon to be developed membrane technologies. Contemporary membrance technologies can already effect major savings in process costs for the conventional fermentation of grains or molasses to produce ethanol; developing membrance technologies could employ cheap cellulosic substrates for ethanol production.

Wind power: Recent developments

Abstract: The work presents the most important developments which have occurred in wind power technology in the U.S. in the last five years. New useful devices and constructions are interpreted and explained by actual case histories, which provide a sound background for action toward combating the energy shortage. Special attention is given to rotor development, wind turbines, and the application of wind power to electric utilities.

Survey of biomass gasification. Volume II. Principles of gasification

Abstract: Biomass can be converted by gasification into a clean-burning gaseous fuel that can be used to retrofit existing gas/oil boilers, to power engines, to generate electricity, and as a base for synthesis of methanol, gasoline, ammonia, or methane This survey describes biomass gasification, associated technologies, and issues in three volumes Volume I contains the synopsis and executive summary, giving highlights of the findings of the other volumes In Volume II the technical background necessary for understanding the science, engineering, and commercialization of biomass is presented In Volume III the present status of gasification processes is described in detail, followed by chapters on economics, gas conditioning, fuel synthesis, the institutional role to be played by the federal government, and recommendations for future research and development

Solar energy perspectives for public power

Abstract: Perspectives on the utilization of solar energy for electricity production and thermal energy utilization by the public are briefly discussed. Wind energy conversion, biomass conversion, solar thermal, OTEC, photovoltaics, and solar heating and cooling are discussed. (WHK)

Energy flows in rural China

Abstract: A quantitative analysis of major rural energy flows in the People's Republic of China shows that the nation 's countryside still depends predominantly on solar radiation transformed by green plants through photosynthesis into food, feed, fuel, and raw materials. Although a large-scale modernization effort currently under way aims to greatly increase the consumption of fossil fuels and electricity, it is argued that the country should not completely abandon its renewable rural energetics.

Energy: an emergency telescoped

Abstract: This article reviews the story of oil price increases and their proximate causes during the years 1974-1979. The social and political consequences of rapid development in the OPEC countries during these years pushed these nations to reevaluate their development plans and hence their need for revenue. The influence of politics on the oil-price increases is discussed in relation to the two largest producers of oil - Saudi Arabia and Iran. In the latter part of this article, the focus shifts to the US and its record in reducing America's dependence on imported oil and in developing a coherent national energy program. Finally, the domestic conventional sources of energy that are the most obvious alternatives to imported oil are discussed: oil, gas, nuclear power and coal. The need to focus on renewable energy sources as well as on energy conservation in general is emphasized. (KRM)

Liquid hydrocarbon fuels from biomass

Abstract: Liquid fuels equivalent to existing commercial products (kerosine, diesel, jet fuel, high octane gasoline) can be produced using biomass type feedstocks. The present status and future projections of the Arizona State University process are described and the potential products and operating conditions summarized. The process is characterized by: (1) multi feedstock capability, (2) mild operating conditions, (3) minimal separation steps, (4) capability of producing several types of quality products, (5) potentially minimal environmental problems. Tasks underway at the research scale include alternate feedstock studies, gasification system optimization, waste stream characterization, and liquid fuels tailoring. A pilot scale facility (10 tons/day) is contemplated with eventual commercialization dependent on results at this stage. (Refs. 7).

Renewable energy sources: the case of brazil

Abstract: Industrial nations have based their economic and social development on the use of fossil fuels (coal, petroleum and natural gas). This trend is being followed by many developing countries which have neither the natural resources nor the manpower to adopt this path. As a result one finds in many of these countries ‘islands of prosperity’ (based on consumption patterns copied from industrial nations) surrounded by a ‘sea of poverty.’ The problems resulting from this dual social structure are obvious in many parts of the world. It is argued here that renewable energy sources are a natural basis for the development of the poorer countries and that intelligent use of hydropower, biomass and direct solar energy can shortcut many of the problems faced today by industrial nations. The case of Brazil is analyzed as one of the countries in which these solutions are being tried.

Solar energy for industrial process heat

Abstract: Findings of study of potential use for solar energy utilization by California dairy industry, prove that applicable solar energy system furnish much of heat needed for milk processing with large savings in expenditures for oil and gas and ensurance of adequate readily available sources of process heat.

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.

Social and economic impact of solar electricity at Schuchuli Village

Abstract: Schuchuli, a small remote village on the Papago Indian Reservation in southwest Arizona, is 27 kilometers (17 miles) from the nearest available utility power. Its lack of conventional power is due to the prohibitive cost of supplying a small electrical load with a long-distance distribution line. Furthermore, alternate energy sources are expensive and place a burden on the resources of the villagers. On December 16, 1978, as part of a federally funded project, a solar cell power system was put into operation at Schuchuli. The system powers the village water pump, lighting for homes and other village buildings, family refrigerators and a communal washing machine and sewing machine.

Wood fuel use in the forest products industry

Abstract: A review is presented of the forest industry perspectives on use of wood fuels. These fuels have a modest heat content, are renewable, and have a low tendency to pollution. Wood fuels are now available in limited quantities, so that the forest products industry obtains 45% of its energy (1.2 quads) requirements from wood. Technologies for combustion and cogeneration can convert wood fuels into useful energy. These methods are costlier and less efficient than comparable oil and gas fired equipment, requiring low cost fuel to be economic. To expand wood fuel use, it will be necessary to provide financial and tax incentives to wood utilization facilities. It will also be necessary to increase supply by restocking forests, improving their management, and continuing R-D in genetics and silviculture.