One of the most significant factors in the megapolis environment in reducing the electricity generation from photoelectric converters (PV) is the contamination of their surfaces. The paper carries out the analysis of various literature sources on the types of pollution and their effect on the operation of the PV, and also the methods for dealing with pollution. The main contamination sources of solar installations are shown to be the soil particles, bird droppings, leaves, snow, air pollutants coming from industrial enterprises, various types of dust associated with human activities, emissions from road transport, etc. The analysis of these studies has indicated that the productivity of the PV is reduced primarily due to carbon contamination, then due to soil particles and calcium carbonate particles. We carried out an experimental study of the influence of various pollution types on the operational effective of solar power plants in Moscow. A series of experiments was carried out in the autumn-winter period, under conditions primarily of low insolation. We covered one of the PV with a layer of dust (ash, snow) at each experiment, the second one (the control one) – was cleaned. The air temperature was 0–2 ºC. Each experiment was conducted for 60-90 min. In addition, before the main series of experiments, we have verified the clean modules, and with their simultaneous contamination. Experimental studies were conducted for the following types of pollution – dust, ash and snow. The experiment showed that: The average error in measuring pure modules is 3% that is consistent with the passport data of the installations. Dry dust in Moscow does not play a significant role in the development of the PV. Wet dust by carbon particles is the main source of reduced power generation by PV (up to 30%). Snowfall leads to a significant decrease in the calculated values of the instantaneous efficiency of modules (over 10%). At low values of insolation, there is a sharp increase in the error in measuring the productivity of the PV.

The paper deals with the issue of providing the Nuclear Power Plant (NPP) by the base load in the nighttime offpeak load hours. In order to search a solution to this issue, we analyze the energy storage technologies including the hydroelectric power stations. Since the construction of this station is associated with various risks (technical, environmental, seismic, etc.), and their deployment in the immediate vicinity of Near Nuclear Power Plants is unacceptable. This implies the tariffs for the power supply from the grid transmission system may exceed the nuclear generating costs 3 or 4 times, and significantly affect the cost for the produced peak energy and competitive advantages of these stations. As more competitive technology of electric energy storage, the paper reviews the system based on utilizing hydrogen energy facilities with hydrogen and oxygen produced by water electrolysis due to excess power from nuclear power plants in the nighttime. The key advantage of these facilities is location in the vicinity of NPPs with the possibility of charging at the cost of the NPP energy. At the same time, hydrogen and oxygen production and their further utilization in the NPP steam cycle has the recurrent nature and connected with the daily startup and shutdown procedures of the main facilities. Thus, the aim of this research is to determine the life cycle of the main hydrogen energy facility under cyclic loads. The fatigue fracture theory is applied to analyze the performance of startup/shutdown cycles in the main hydrogen energy facility in combination with the NPP. We have conducted the estimation of fatigue crack growth depending on the load frequency for the critical components of electrolysis plants, compressors, metal hydrogen and oxygen storage tanks, as well as hydrogen-oxygen combustion chambers. The paper focuses on the impact of hydrogen corrosion on the rate of fatigue crack growth and proposes criterion defining the number of cycles occurred prior to the fracture extension process. Based on the criterion of maximum cycles prior to the fraction extension process, we have defined the boundaries for effective performance of the main hydrogen energy facility.

In order to protect the hermetic enclosure and the equipment and systems of the reactor installation housed in it from damage caused by the ignition (explosion) of hydrogen, the overwhelming majority of nuclear power plants with pressurized water reactors are provided with a hydrogen concentration monitoring system and an emergency hydrogen removal system. These systems prevent the formation of explosive mixtures in the accident localization zone by maintaining the volume concentration of hydrogen in the mixture below the safety limits which ensures the preservation of the density and strength of the hermetic enclosure and the operability of other localizing security systems. A key component of the emergency hydrogen removal system is a passive autocatalytic hydrogen recombiner which operation is based on the principle of catalytic recombination of hydrogen and oxygen. There is an urgent need for a full-scale dynamic calculation of the development of emergency conditions in a nuclear power plant container accompanied by a large release of hydrogen. In order to achieve this goal, we have constructed and justified a simple engineering thermohydraulic model of hydrogen removal in the operation of the PAR based on the available experimental data. The paper presents the application results of the model as a part of contour industry codes: RELAP, TRACE, and CORSAR, intended, among other things, for carrying out multifactor and fullscale calculations of the dynamics of emergency processes with the release of hydrogen into the nuclear power plant premises. This model allows us to substantiate the dynamics of local concentrations of gas components of the mixture in a confined space, the temperature of the mixture, the catalyst and the walls of the box, the pressure when hydrogen or steam is supplied to the box. We have analyzed various rates of hydrogen supply to a closed box in order to numerically substantiate the time when the concentration reached the maximum level. Moreover, we have calculated the performance for several entrance concentrations of hydrogen, and obtained a satisfactory agreement between the dynamics of the concentrations, temperatures of the catalyst and gas, and the productivity of the passive autocatalytic hydrogen recombiner. These calculations are based on the results of the calculated and the available experimental data comparison.

Serious constraining factors in the development of fuel hydrogen energy are: high production costs of hydrogen, ineffective technologies for transportation and storage of both liquid and compressed hydrogen, as well as the lack of logistic supply chains and fuel filling infrastructure. For example, transportation costs for compressed hydrogen gas are comparable with, and sometimes exceed the production costs. The safe drain free storage of hydrogen with minimal losses has a particular relevance when infrastructure for liquid hydrogen production, transport logistics chains for its delivery, distribution and storage are created. The authors have considered the different schemes of the condensation cycles with the standard helium refrigerators, both with and without of precooling by liquid nitrogen of the main hydrogen stream. The paper gives the analysis of operating costs in condensing and traditional JT cycles of hydrogen vapor recondensation and compares them for this indicator. The connection of the second expander in the helium liquefier scheme is shown to lead not only to increase in the capital cost and complicate it technologically but also reduce the operation costs of the condensation process slightly. In case of cryogenic systems with the drain free storage of liquid hydrogen at filling stations and terminals, we have considered two temperature levels of the hydrogen vapor entering condenser directly from the vapor collector at 300 K and from the gas space of the cryogenic tank at 30 K. It is concluded that it is possible and expedient to use the standard helium refrigerators for the recondensation cycles in systems of drain free storage, by including them in the general structure of filling stations.

In this work, we carry out the high-resolution electron microscopy of microstructure of grains boundaries of anion and electronic conductors in composite Ni/YSZ anodes before and after study of the current–voltage characteristics of model SOFCs. We propose a mechanism of 2-stage reaction of hydrogen oxidation occurring in the vicinity of triplephase boundary of Ni/YSZ SOFC anodes. On the first stage, metallic nickel is oxidized to nickel oxide by oxygen anion coming from the solid electrolyte membrane. On the second one, hydrogen reduces nickel oxide to metallic nickel, and water is formed. Decrease of the Ni grains size in the vicinity of contact with anion conductor grains is shown to be the result of NiO nano-grains appearance and their consequent reduction to metallic Ni during SOFC operation. High-resolution electron microscopy analysis demonstrates the significant changes in microstructure of grains boundaries of anion and electronic conductors in composite Ni/YSZ anodes after application of load current to SOFC. Nano-sized NiO grains appear in near-boundary regions of Ni grains after current tests. Orientation alignment between YSZ and nano-sized NiO lattices is unambiguous evidence of epitaxial growth of nickel oxide at YSZ surface as on a substrate that is possible only as a result of oxygen anion transport from anion conductor YSZ to the metal surface during current passage through the solid oxide fuel cell. We study the chemical transformations in the electrochemical reaction zone in SOFC composite electrodes depending on the current density passing the SOFC by new “in-situ” Raman spectroscopy technique. Increase of the current passing is shown to lead to growth in the intensity of Raman peak connected with symmetric oscillations of CeO₂ group. We connect this result with the change of the cerium cations charge state from Ce³⁺ to Ce⁴⁺ and consider this to be direct proof of the charge transfer in composite anode via oxygen anion transfer.

The paper contains general information on the environmental impact assessment of the projects in Russia in compliance with the relevant federal legislation taking into account changed and additions. The paper describes the main types of environmental expertise applied in Russia, and the main objects of compulsory state ecological expertise in power engineering of the federal level including first of all gas, oil and coal-fired power plants. We have analyzed the current situation related to the tightening of the Russian environmental legislation and the corresponding impact of scientific and technical environmental expertise on the BAT implementation. The paper lists the chief reasons for a lack of the independent scientific environmental assessment of energy projects. At the same time, we note that a special role should be assigned to higher educational institutions and research institutes with scientific staff being professionals in various energy issues. Based on 20 years’ experience of the Centre for Science and Education “Ecology of Power Engineering” of the Moscow Power Engineering Institute, we have considered the issue of ecological training of personnel from energy holding and companies. The authors' views on the expertise on management of wastes (coal ash) from thermal and electric energy production are considered, taking into account the legal and normative-technical documents. The paper presents a block diagram of the prospective coal ash handling system of thermal power plants and the modernized structural scheme of the prospective ash and slag removal system of TPPs. The block diagram provides the possibility of maximum collection and shipment of dry ash as well as environmentally acceptable ways of storing the unclaimed dry ash. The paper describes the examples of the implementation of the ash handling modernization projects at State District Power Plants with different levels of expertise compliance with the current trends in the development of ash handling systems using the best available technologies in the power engineering.

The paper deals with a characteristic feature of the discharge process of the cathode of a lithium-oxygen current source (LOCS) with the electrolyte based of a nonaqueous solvent, which is the clogging the positive electrode pores with the insoluble electrolyte and nonconductive reaction product, lithium peroxide Li₂O₂. Lithium peroxide is formed in a multistage complex reaction occurring in the course of oxygen reduction. In the reverse process, i.e., anodic LOCS charging, lithium peroxide accumulated in the course of discharge is decomposed with formation of lithium ions, oxygen molecules, and electrons. It is advisable to obtained as much as possible lithium peroxide during the LOCS discharge. However, it “clogs” the cathode pores, prevents the flow of oxygen into them, that, in turn, complicates the further lithium peroxide accumulation.  Thus, the calculations show that the cathode discharge process can be mainly carried out only in a relatively thin porous layer bordering on the gas phase. Therefore, in the absence of special measures, the capacity calculated per square centimeter of the outer cathode surface is small. Usually, when the functioning of the active cathode layer is studied, a certain value is assumed for the oxygen consumption that is the main constant of the LOCS charging process (its value is characterized by parameter k). This paper uses computer simulation with variation of k in a wide range. The corresponding variation of the overall characteristics of the LOSC cathode is demonstrated. The causes of the changes in the cathode pores are explained. The study shows that a decrease in constant k (which lead to a decrease in consumption of oxygen intended for formation of Li₂O₂) and an increase in the pore radius (at a transition from micropores to mesopores) result in an increase in the specific cathode capacitance and the amount of lithium peroxide accumulated in the cathode and not in their decrease.