Preview

Alternative Energy and Ecology (ISJAEE)

Advanced search
Open Access Open Access  Restricted Access Subscription or Fee Access
No 13-15 (2019)

I. RENEWABLE ENERGY 6. Small Hydroenergetics

12-23 1076
Abstract
The paper discusses the problem of using the energy of rivers without creating the dams and flooding vast areas and notes that there is a progress in the implementation and development of the ideas of patent in 1931 (the speed of the workers turbine blades is higher than flow rate). The paper gives the diagrams of the new turbines of this type, for example a balanced 6-tier single-blade turbine, turbine-spiral, a balanced twoblades turbine. Moreover, the paper deals with the features free-threaded orthogonal turbines in the streams of the limited width and depth. The most important characteristic of a turbine is the turbine's power factor that is equal to the ratio of the energy of the rotating turbine to the kinetic energy of the flow in the current tube passing through the turbine circuit. There is a possibility of a significant increase in the power of the turbine in comparison with the conditions of use unlimited streams. The increase in turbine power in a straitened flow is associated with an increase in the flow velocity in the turbine on the approach to the rear section of the blades’ track. It is set the requirements of the turbine parameters for maximum power at a given water flow and the permissible level rise in the river. These requirements relate to the certain rules for selecting the number of blades (and solidity) of the turbine, taking into account the permissible increasing in the water level (backup) in front of the turbine. The paper notes the turbines instability at low speed of rotation, describes a turbine design modification that eliminates this drawback. Modification of the high-speed orthogonal turbines is the use of accelerating blades with a cup-shaped cross-section, placed on the route within a diameter 2 times smaller than the diameter of the main (working) blades of the smoothly streamlined profile. It is concluded that all considered variants of turbines for streams with limited cross-section, the design of the blade system may be made rigid, which eliminates the single central shaft (axle), replacing it with a reference semi-shafts.

II. НЕВОЗОБНОВЛЯЕМАЯ ЭНЕРГЕТИКА 9. Атомная энергетика

24-39 867
Abstract
The paper gives the analysis of the problem of the primary current frequency regulation in the power system, as well as the basic requirements for NPP power units under the conditions of involvement in the primary regulation. According to these requirements, the operation of NPPs is associated with unloading and a corresponding decrease in efficiency. In this regard, the combination of nuclear power plants with a hydrogen complex is shown to eliminate the inefficient discharge mode which allows the steam turbine equipment and equipment of the reactor facility to operate in the basic mode at the nominal power level. In addition, conditions are created for the generation and accumulation of hydrogen and oxygen during the day, as well as additionally during the nighttime failure of the electrical load which allows them to be used to generate peak power.  The purpose of the article is to assess the systemic economic effect as a result of the participation of nuclear power plants in combination with the hydrogen complex in the primary control of the current frequency in the power sys-tem, taking into account the resource costs of the main equipment. In this regard, the paper gives the justification of cyclic loading of the main equipment of the hydrogen complex: metal storage tanks of hydrogen and oxygen, compressor units, hydrogen-oxygen combustion chamber of vapor-hydrogen overheating of the working fluid in the steam turbine cycle of a nuclear power plant. The methodological foundations for evaluating the working life of equipment under cyclic loading with the participation in the primary frequency control by the criterion of the growth rate of a fatigue crack are described. For the equipment of the hydrogen complex, the highest intensity of loading is shown to occur in the hydrogen-oxygen combustion chamber due to high thermal stresses.  The system economic effect is estimated and the effect of wear of the main equipment under cyclic loading is shown. Under the conditions of combining NPP power units with a hydrogen complex, the efficiency of primary reg-ulation is shown to depend significantly on: the cost of equipment subjected to cyclic loading; frequency and intensity of cyclic loading; the ratio of the tariff for peak electricity, and the cost of electricity of nuclear power plants.  Based on the developed methodology for assessing the effectiveness of the participation of nuclear power plants with a hydrogen complex in the primary frequency control, taking into account the damage to the equipment, the use of the hydrogen complex is shown to provide a tangible economic effect compared with the option of unloading nuclear power plants with direct participation in frequency control.
40-51 863
Abstract

Currently, the Unified Energy System of Russia has a tendency to increase the deficit of peak and semi-peak capacities with a simultaneous increase in the number of NPP which requires the participation of NPPs in a variable part of the schedule electrical loads. In addition to the economic need to maintain the installed capacity utilization rate at a high level, there are technological limitations for maneuvering characteristics for NPPs. The authors have developed an approach to solving this problem based on combining with an environmentally friendly energy source – an autonomous hydrogen complex which includes heat accumulators and an additional multifunctional low-power steam turbine installation. The developed power complex can also provide reliable redundancy of power supply of NPP own needs in the event of a total station blackout. The paper carries out the evaluation of the technical and economic parameters of the main equipment of the autonomous hydrogen complex required for combination with a two-unit NPP with a VVER-1000. Based on the assessment of inflation indicators of the Russian economy over the past 11 years, three options have been identified for fuel cost and tariff rates for electricity (capacity), as well as the size of operating costs, including depreciation in the main equipment, taking into account current pricing principles. As a result, the values of accumulated net present value were obtained depending on the ratio of the cost of semi-peak and non-peak electricity tariffs at different inflation rates. We have taken into account the positive economic effect of reducing the risk of damage to the reactor core, replacing the construction of gas turbines as a maneuverable source of electricity in the power system, and increasing the income of the federal budget of the Russian Federation from saving natural gas. The economic conditions of competitiveness of the proposed approach to improving the maneuverability and safety of NPP are determined. The highest economic efficiency is achieved with the maximum projected inflation which is associated with the maximum discount rate and high rate of growth of electricity tariffs. Reducing the risk of damage to the core allows us to provide the competitiveness of the proposed approach in all considered variants of inflation and the ratio of electricity tariffs.

IV. HYDROGEN ECONOMY. 12. Hydrogen Economy

52-61 738
Abstract

The statistical theory of hydrogen-sorption properties of compounds of alkaline and alkaline-earth metals M(BC)nHx (M = Li, Mg; 0 ≤ x ≤ 12, n = 1,2) has been developed in this paper in the expectation that such hydrogenated boron carbides will be the reliable materials for the reversible accumulation and storage of hydrogen in large quantities in perspective. The calculation of free energy of these crystals has been performed on the basis of molecular-kinetic notions, the equation of thermodynamic equilibrium of such system, determining the P-T-c phase diagram, has been derived in the present paper. The hydrogen solubility in these compounds has been ascertained in dependence on temperature and external pressure, the possibility of manifestation of hysteresis effect has been justified. The derived formulae allow to establish the P, T-conditions of high hydrogen content in boron carbide systems and can permit to select the optimum composition of material choosing for hydrogen storage, the regime of technological process, to develop the experimental technology for solving of the practical problems, if in this case the energetic parameters of these materials are known from independent experiments.

62-87 961
Abstract

All the main areas of energy development suggest or are already implementing the use of metal-hydrogen systems. For nuclear energy, this is associated with the creation of thermostable moderators and special-purpose construction materials, for thermonuclear energy, with the behavior of the so-called first wall of fusion reactors, for hydrogen energy — storage, transportation and extraction of hydrogen. Hydrogen is the most effective moderator of fast and thermal neutrons, especially at high volumetric concentrations of hydrogen atoms in the material, i.e. at a high value of the ratio of the number of hydrogen atoms to the number of metal atoms, taking into account the heat resistance of the hydride. This paper discusses the modern methods of experimental studies of heterogeneous reactions, the topochemistry of metal – hydrogen reactions, the dependence of the interaction rate on pressure and temperature, models of surface processes occurring during the interaction of hydrogen with metal.  Methods for determining the probability of adsorption of hydrogen on a metal surface, methods for measuring the activation energy of dissociation of a hydrogen molecule on a surface are also discussed. The paper describes the fea-tures of the preparation of the reactor, experimental samples and the method of their study in the study of atomic hydrogen-metal systems, the method of plasma-chemical thermogravimetry used to study heterogeneous reactions occurring in a hydrogen plasma electrodeless discharge. In order to study the mechanism of interaction of hydrogen with hydride-forming metals, a kinetic method of research is proposed. The essence of the kinetic method is that the elimination of the limiting influence of surface and diffusion processes on the rate of hydride formation using atomic hydrogen and metal foil makes it possible to directly record the formation of the corresponding phases using hydro-gen-metal kinetic curves, and also study the effect of various parameters on the rate of interaction and the formation of hydride phases.  

88-100 2082
Abstract

The research uses the method of high-temperature thermogravimetric analysis to study the processes of interaction of the gas phase in the temperature range 300–950 °C in the partial pressure ranges of oxygen 8.1–50.7 kPa, water 6.1–24.3 kPa and hydrogen 4.1 kPa with La1–xSrxScO3–α oxides (x = 0; 0.04; 0.09). In the case of an increase in the partial pressure of water vapor at a constant partial pressure of oxygen (or hydrogen) in the gas phase, the apparent level of saturation of protons is shown to increase. An increase in the apparent level of saturation of protons of the sample also occurs with an increase in the partial pressure of oxygen at a constant partial pressure of water vapor in the gas phase. The paper discusses the causes of the observed processes. The research uses the hydrogen isotope exchange method with the equilibration of the isotope composition of the gas phase to study the incorporation of hydrogen into the structure of proton-conducting oxides based on strontium-doped lanthanum scandates. The concentrations of protons and deuterons were determined in the temperature range of 300–800 °C and a hydrogen pressure of 0.2 kPa for La0.91Sr0.09ScO3–α oxide. The paper discusses the role of oxygen vacancies in the process of incorporation of protons and deuterons from the atmosphere of molecular hydrogen into the structure of the proton conducting oxides La1–xSrxScO3–α (x = 0; 0.04; 0.09). The proton magnetic resonance method was used to study the local structure in the temperature range 23–110 °C at a rotation speed of 10 kHz (MAS) for La0.96Sr0.04ScO3–α oxide after thermogravimetric measurements in an atmosphere containing water vapor, and after exposures in molecular hydrogen atmosphere. The existence of proton defects incorporated into the volume of the investigated proton oxide from both the atmosphere containing water and the atmosphere containing molecular hydrogen is unambiguously shown. The paper considers the effect of the contributions of the volume and surface of La0.96Sr0.04ScO3–α oxide on the shape of the proton magnetic resonance spectra.

XXII. INFORMATION FOR AEE. 41. Information

41-6-0-0 Advertising Matters of Investment Companies and Manufacturers

41-15-0-0 News

 
118-129 259


ISSN 1608-8298 (Print)