Showing papers on "Electricity generation published in 1977"

Solar Energy Conversion with Fluorescent Collectors

Abstract: A new principle for solar energy conversion is proposed and evaluated theoretically. Collection and concentration of direct and diffuse radiation is possible by the use of a stack of transparent sheets of material doped with fluorescent dyes. High efficiency of light collection can be achieved by light guiding and special design of collectors. The optical path length in a triangular collector is computed. In combination with solar cells this type of collector offers the advantage of separating the various fractions of light and converting them with solar cells with different bandgaps. Theoretical conversion efficiency under optimum conditions is 32% for a system with four semiconductors. Thermal energy conversion offers several advantages over conventional collectors: High temperature and efficiency even under weak illumination, separation of heat transport and radiation collection, low thermal mass. Thermal efficiency is computed to be between 42% and 60%. Very attractive appear hybrid systems for generation of thermal and electric energy. An estimate of the economics of electricity generation shows that due to the concentration costs can be much lower than possible today. With the use of only silicon cells the breakeven point of $0.5/W is almost reached. Practical difficulties to be solved are: Synthesis of dyes with stringent requirements, identification of plastic materials with high transparency and development of solar cells with higher bandgaps.

Electric power generation

Abstract: Electric power is generated from a non-uniformly operating energy source such as wind or water waves by driving hydraulic pump means by a wind wheel or a bobbing float The pump feeds hydraulic medium into a cylinder to raise a piston loaded by a weight When the weight rises above a predetermined level, the medium is fed under its constant pressure to drive an hydraulic motor connected to an induction generator Because the generator is driven at constant power (though intermittently) it can be connected to the public mains supply, eliminating the need to store power, without sophisticated interface arrangements A second generator connected to a resistive space or water heating load can be cut in at higher energy levels The hydraulic pump can be arranged to extract power from the source in the most efficient way

Submarine turbine power plant

Abstract: A power plant for the generation of electricity from the flow of water currents uses turbine wheels within nozzles submerged in the water current, anchored to the bottom of the water course, as for example, the ocean, and self-buoyed to a level well below the water surface Pairs of counter-rotating turbines are supported by their rims, which bear against friction drive wheels, which in turn drive electrical generators contained in water-tight machine rooms within the wall of the nozzle A structural design is disclosed, providing for the building of modules of the nozzle ashore, which modules may then be barged to the deep-water site for assembly into the whole power plant

Planning Electric Power Generation: A Nonlinear Mixed Integer Model Employing Benders Decomposition

Abstract: This paper describes the development and application of an optimization program that is used to help electric utilities plan investments for power generation. For each year over a planning horizon the program determines what types and sizes of generating plants should be constructed, so as to minimize total discounted cost while meeting reliably the system's forecasted demands for electricity. The problem is formulated as a large-scale, chance constrained, mixed integer program. The solution algorithm employs Benders' Partitioning Principle, a mixed integer linear programming code, and a successive linearization procedure. Computation costs are low and, in the important area of sensitivity analysis, the program offers special economies which make it attractive to power system planners. Computational results are presented for a full sized generation planning problem for the six New England states where the algorithm is currently being used for planning generating facilities.

Wave powered electric generator

Abstract: A wave powered electric generator using direct energy conversion is described which includes, within a water and airtight, buoyant envelope tethered to a fixed point relative to the sea bottom, one or more stators and one or more elements moveable by the force of inertia, the relative motion of the moveable element within the stator generating electricity. Also within the buoyant envelope is a rectifier for rectifying the electric energy generated by the moveable element, and power transmission means for supplying the generated and rectified electric energy to a power station. In a preferred embodiment, a conductive fluid is employed as a moveable element, this fluid being passed through a concentrated magnetic field, the resultant electrical power being tapped by electrodes whose axis preferably is orthagonal to the field and direction of fluid motion.

Solar energy window

Abstract: An energy absorbing venetian blind type device for generating electricity,roviding heat, and serving as a sun shade. A plurality of slats covered with an array of photovoltaic cells are enclosed between two panes of glass of a window housing. A heat removal system using forced air cools the photovoltaic cells and collects heat for heating purposes elsewhere. The electricity generated by the photovoltaic cells is collected for immediate use or stored in storage batteries for later use.

Inter-Fuel Substitution Possibilities: A Translog Application to Intercountry Data

Abstract: One of the pressing issues in current energy policy debates in both the U S and other consuming countries is the feasibility of substantially reducing the use of crude oil In some energy consuming sectors suchl as transportation, the shortrun mechanism to reduce consumption is through lower utilization of energyconsuming equipment while in the long-run, the equipment can be redesigned to achieve greater fuel efficiencies In electricity generation and heatilng uses the primary mechanism to reduce consumption is inter-fuel substitution rather than capital/energy substitution This paper is concernied with estimating the interfuel substitution relationships between fossil fuels (coal, gas, and residual fuel oil) in the generation of electricity It is important to consider fossil fuel substitution possibilities in electricity generation both because considerable technical flexibility exists2 and because electric utilities are large consumers of fossil fuels For example, electric utilities consumed 25% of primary energy inputs in the U S in 1970 Although not as high as the U S, the other developed countries exhibit a similar pattern In the 20 0 E C D coun-tries, electric utilities consumed 50% of the coal, 17% of the gas, and 11% of petroleum products3 High substitution elasticities among fuels in electricity generation indirectly increase subsequenit substitution of electricity for petroleum as a fuel source in residential, commercial, and industrial sectors Thus the nature and extent of inter-fuel substitution possibilities in electricity generation are fundamental to the question of reducing dependency on crude oil There have been several econometric studies of inter-fuel substitution in electricity generation using a variety of estimation procedures and samples MacAvoy [15] used cross sectional data for U S power regions to examine substitution between nuclear fuel and fossil fuel Griffin [10] estimated dynamic price and cross price elasticities among fuels utilizing annual time series data More recently, Joskow and Mishkin [13] used individual plant data to analyze fuel choice in a logit model framework But probably the approach capturing the most attention is the application of

Strategy for energy conservation through tribology

Abstract: Tribology is defined as an interdisciplinary science that deals with the physical, chemical, and metallurigal phenomena of interacting surfaces in relative motion. It is concerned with studies of lubrication, friction, wear and the properties of lubricants and bearing materials. A study was conducted to determine the energy conservation potential of tribology research and development programs related to equipment for road transportation, power generation, turbomachinery, and industrial machinery. The study determined that funding of the recommended R and D plan and implementation of its findings offer the potential of conserving up to one tenth of the total U.S. energy consumption. In terms of the 1976 energy expenditure rate based on oil at $12/bbl, this represents a saving of over $16 billion; or nearly one and a half billion bbl of oil per year. Not included in these figures is the payoff in the areas of raw material usage, life of machinery, manufacturing costs, etc., which ultimately translates into substantial additional savings of energy and other national resources. (LCL)

Solar power from satellites

Abstract: Microwave beaming of satellite-collected solar energy to earth for conversion to useful industrial power is evaluated for feasibility, with attention given to system efficiencies and costs, ecological impact, hardware to be employed, available options for energy conversion and transmission, and orbiting and assembly. Advantages of such a power generation and conversion system are listed, plausible techniques for conversion of solar energy (thermionic, thermal electric, photovoltaic) and transmission to earth (lasers, arrays of mirrors, microwave beams) are compared. Structural fatigue likely to result from brief daily eclipses, 55% system efficiency at the present state of the art, present projections of system costs, and projected economic implications of the technology are assessed. Two-stage orbiting and assembly plans are described.

Geothermal energy conversion system

Abstract: A geothermal energy recovery system of improved efficiency makes use of thermal energy stored in hot, solute-bearing well water as it is pumped upward to the earth's surface through an extended heat exchange element for continuously heating a downward flowing organic fluid to a supercritical state. Some of the energy of the latter fluid is used within the well for operating a turbine-driven pump for pumping the hot, solute-bearing well water at high pressure and always in liquid state to the earth's surface, where it is reinjected into the earth in another well. The temperature difference between the upward flowing brine and the downward flowing organic fluid is maintained finite in a predetermined manner along the subterranean extended heat exchange element. After driving the deep-well turbine-driven pump, the organic fluid arises to the earth's surface in a thermally insulated conduit; at the earth's surface, vapor turbine electrical power generation equipment is driven by the heated organic fluid which is then returned into the well for reheating in the extended heat exchanger.

A power system stabilizer for thermal units based on derivation of accelerating power

Abstract: Exciter stabilizing signals derived from shaft speed measurement have the potential to create torsional oscillations in turbo-generator units. Signals derived from accelerating power preclude this problem, but require an input proportional to mechanical power changes for satisfactory operation. A mechanical power signal has been derived from measurement of steam pressures and has been static exciter in the field.

An Application of the Economic-Environmental Power Dispatch

Abstract: An application of a decision approach for controlling air pollution emission from power generation, presented by the authors in an earlier paper, is described. Trade-off curves between pollution emission and total operating cost are first computed for a portion of a realistic system containing coal, oil, and gas turbine generation. Points on the trade-off curve are then mapped into an exposure measure by using an air pollution diffusion model for the region being analyzed. The computations were carried out for several demand levels and various weather conditions. A comparative analysis of the results and their implications to power dispatch decisions are discussed.

Method and apparatus for generating electricity from the flow of fluid through a well

Abstract: A method and apparatus for generating electricity from a generator driven by the flow of fluid flowing from a fluid producing well. A fluid driven motor is positioned in the pipeline adjacent to or above the well head such that the fluid passes through the motor to turn the motor shaft to drive the generator. By controlling the electrical load connected to the generator, the force required to drive the motor and thereby the pressure reduction across the motor can be controlled. The electricity produced by the generator may be used to heat the fluid in the pipe to prevent freezing of the fluid. The electricity can be utilized to heat the emulsion in an emulsion separator dehydrator for separating gas, water, and oil prior to its introduction into the pipeline. Separate motor may be utilized for gaseous fluid and liquids. Where the well produces both gas and liquid a separator is employed to separate the gas and liquid.

Tidal power plant and method of power generation

Abstract: A plurality of tidal chambers are filled in succession during rising tide and then are allowed to sequentially empty during the half-cycle of falling tide. Power is generated by air flow across a turbine, as a manifold and valve means communicate air pressure from the tidal chambers during rising tide and vacuum pressure during falling tide. Sequential operation of the tidal chambers permits continuous generation of power during the full cycle of rising and falling tide.

Effect of generalized wind characteristics on annual power estimates from wind turbine generators

Abstract: A technique is presented for estimating the average power output of a wind turbine using, as the wind characteristic input, only the mean annual wind magnitude. Hourly wind speeds are assumed to have a Rayleigh frequency distribution which requires a single parameter input (e.g., the mean value, variance or higher moment values). Based upon a general shape, for the wind speed versus machine output, a generic set of curves is developed to estimate the average power output of wind turbines. Also, estimates of the percent of time the wind turbine would not produce power (percent down time) and the percent of time the wind turbine would be operating at its rated power are presented.

A mathematical model for long range expansion planning of generation and transmission in electric utility systems

Abstract: This paper provides a mathematical model (linear mixed integer program) for the problem of selecting an expansion plan over a planning horizon for an electric utility system. The objective function that is chosen is the minimization of the net present value of the capital investment cost associated with the construction of power plants and transmission lines plus the operating costs of the system. The restrictions associated with the problem are the requirement to satisfy the forecasted demands of the systems for electrical energy plus the physical restrictions that result from having limited capital resources and plant site limitations. The model provides construction expansion schedules for power plants and transmission lines (i.e. what capacity to build, where the additional capacity is to be located, and when it is to be completed). Additionally, an approximate operating schedule for plants and transmission lines is provided. An application of the modeling technique to a regional electrical utility system illustrating the formulation methods and the results that can be obtained is given.

Power generation from refinery waste heat streams

Abstract: The integration of a petroleum refinery, or a petrochemical complex, with an off-site power facility in which the latter provides a vaporizable coolant for vaporization in the former. Vaporization is effected through indirect contact with one or more waste heat streams; the resulting vapors are expanded through a turbine, to a lower pressure, from the resulting motion of which power is generated. In most instances, the process generates more power than its connected load. Preferably, the coolant is indirectly contacted, at elevated pressure, with a plurality of refinery process streams in series and in the order of increasing temperature. Resulting vaporized coolant phases are passed through individual turbines, or through different stages of a multiple-stage turbine.

Home power station

Abstract: A generator is driven by a miniature hydraulic turbine which, in turn, is driven by water flowing to, through or from the water system of a residential or commercial building. Electricity generated by the generator is stored in storage batteries for emergency or supplemental use. A distribution panel is operable to give a readout of the amount of stored electricity. The readout can be obtained by pushing a button on the distribution panel and such readout directly and immediately informs the reader of the number of hours a specific appliance can be operated by the stored electricity.

Charged aerosol generator with uni-electrode source

Abstract: This invention relates to novel charged aerosol sources for diverse applications in Heat/Electric Power Generation, weather modification, airport fog clearance, dispersed chemical reactions, and other uses; and in particular, to a Wind/Electric Power Generator deriving electric power from wind power directly without moving mechanical parts through the medium of charged water droplets introduced into the airstream from a charging electrode, the charged droplets eventually discharging to ground, the electrical load being connected between the charging electrode and ground to complete the circuit. The wind/electric power is converted by an isobaric electrothermodynamic process occurring in the space charge field produced by the charged droplets, which are efficiently produced by novel charging devices on the charging electrode. The Wind/Electric Power Generator can be fabricated to extend across large areas of windstream to generate large electric power output at high voltage, and means are described for its conversion to standard 60 Hz, 110 V power.

Binary vapor cycle method of electrical power generation

Abstract: A binary vapor cycle method of electrical power generation is disclosed wherein two refrigerant fluids can be used to operate an apparatus for the generation of mechanical power as well as electrical power generation. This method, which is essentially a dual heat pump system, offers an approach to utilizing the advantages of two different refrigerants within a single apparatus. This advantage is particularly advantageous in the ulitization of low specific energy sources, such as two water sources which exist in close proximity to each other, but at different temperatures. Thus, water, which itself is a heat pump fluid, can be used as a means of transmitting heat energy to a second heat pump fluid, or refrigerant, without incurring the disadvantages of water, or water vapors, as a means to produce power, because of its high specific volume and low saturation pressures at low temperatures. Additionally, since the warm water source of energy most commonly available is in the form of reservoirs, such as the ocean waters, and the utilization of barometric legs to bring the warm water into contact with the process, eliminates the use of expensive heat exchangers, which is the case of ocean water, are subject to fouling and loss of efficiency due to clinging microorganisms.

An initial comparative assessment of orbital and terrestrial central power systems

Abstract: A silicon photovoltaic orbital power system, which is constructed from an earth source of materials, is compared to likely terrestrial (fossil, nuclear, and solar) approaches to central power generation around the year 2000. A total social framework is used that considers not only the projection of commercial economics (direct or in internal costs), but also considers external impacts such as research and development investment, health impacts, resource requirements, environment effects, and other social costs.

Solar energy converting device

Abstract: In abstract a preferred embodiment of the present invention is an energy converting device adapted to be utilized for the generation of electricity. The energy converting device of the present invention comprises a solar heat collecting main structure positioned generally over a subterranean well. Air which has been channeled to the base of said well is initially heated and caused to rise. Additional thermal energy is added to said air by solar energy collected by said main structure. Disposed about an uppermost end of said solar collecting main structure is a windmill assembly which is rotatively driven by rising channeled air passing through the solar collecting main structure. An electrical generator is operatively connected to the windmill assembly and driven thereby such that electricity is generated as the windmill assembly is driven.

Status Report on Closed-Cycle Power Plants in the Federal Republic of Germany

Abstract: In recent years the constructors as well as the users of municipal and industrial power plants have shown a rising interest in the closed-cycle gas turbine. Because of its ability to deliver a large amount of heat without restrictions to the electric power generation, the closed-cycle gas turbine is most favorably qualified for central district heating of large residential quarters. In this paper these aspects of the closed-cycle will be illustrated in the frame of five closed air turbine plants, being in operation in the FRG. The layout of and the operation experience gained with these plants will be discussed. These municipal and industrial power plants are fueled by coal, oil, gas, or even mixtures of these. The special items in the layout of the heaters with respect to the different fuels are shown; the perspectives for further design are discussed.

Electrical power systems. Volume 2

Abstract: This textbook is intended for university and technical students studying electrical power systems. Each chapter provides an introduction, definitions, and basic theory development. This volume contains information on power system protection; circuit interruption and switching overvoltages; stability of power systems; travelling waves in transmission lines; insulation coordination; rectification, inversion and high-voltage dc systems; 3-phase network matrices and coordinate system transformations; power system analysis; and aspects of system integration and development. Appendices on matrix algebra and the economics of electrical power generation are included. (LCL)

Sulfur-fueled magnetohydrodynamic power generation

Abstract: An improved, closed-cycle magnetohydrodynamic (MHD) power generation system wherein the MHD generator is fueled by sulfur burned in oxygen, together with stages for recovering sulfur dioxide, reducing SO 2 to elemental sulfur, and returning reduced elemental sulfur to the MHD unit such that higher flame temperatures and ionization factors are obtained while pollutants typically generated by fossil-fueled MHD power generation systems are essentially eliminated.