A study was conducted of the transmission of electric energy to consumers through the electric networks of the branch of PJSC Rosseti South – Astrakhanenergo was carried out. The analytical assessment was performed for electric networks with rated voltages of 110, 35, 6 – 10 and 0.4 kV. The characteristic features of the company's electric networks are noted, its structural characteristics are given, and the balance of electric energy during its transmission over electric networks of all rated voltage levels is considered. Based on initial data published in the public domain, an analysis of emergency outages in the studied electric networks for the period 2018 – 2022 was carried out. At the same time, the quantitative characteristics of failures are considered, as well as their consequences in terms of undelivered electricity to consumers, as well as the economic damage caused by the duration of the emergency outages. It was found that 18,344 emergency outages occurred during the study period, resulting in 1,073.2 MWh of electric energy not being supplied to consumers. At the same time, the economic damage from the undelivered energy amounted to 267,368.59 thousand rubles. The main groups of causes for the emergency shutdowns have been identified, with about 93% of them attributed to non-compliance or failure to meet the required schedules for equipment maintenance and repair, as well as external mechanical effects on elements of electric networks. The analysis of the projected number of failures for these reasons in 2025 has shown that the number of failures is expected to remain virtually unchanged. Based on the findings, recommendations have been formulated for the company's management to improve the reliability of power transmission. The obtained research results may be of interest to the management of Astrakhanenergo, other electric grid companies, as well as engineering and researchers investigating issues of power transmission reliability.

This study presents general approaches to forming a list of measures to improve the reliability of heat supply systems. An assessment of the reliability indicators for heat supply systems of district heating network sections and consumers was conducted. Heat supply schemes were transformed while maintaining the logical interconnection between elements, and the main calculation stages for several combined heat and power plants (CHPP) are presented. The following results are provided: processed data on failures and repairs of heating network sections within a CHPP heat supply system, and an assessment of heat supply reliability indicators for the CHPP consumers. A calculation was performed based on a selected logical criterion for the following system reliability indicators using the Zulu Thermo software package: probability of failure-free operation; availability factor; average total heat supply shortfall; distance from the source, m; probability of failure; recovery rate; failure rate; failure flow. To facilitate the analysis of reliability indicators, additional modeling of the thermal-hydraulic operating regime of heating networks was carried out; adjustment and verification calculations were performed. An approach to forming a list of measures for improving the reliability indicators of heat supply systems is proposed, based on a matrix method that involves constructing dependencies of risk changes on the probability of failure and the total heat energy shortfall. The application of algorithms for developing a list of measures to improve the reliability indicators for consumers and sections of heating networks is substantiated.

Methods have been investigated for the accelerated restoration of power transmission lines. A concept is presented for a rapid restoration system for power transmission lines based on mobile support structures and a modular, container-type repair station. Modern approaches to enhancing power system resilience are examined, including quick-assembly aluminum-composite towers, mobile substations, unmanned aerial vehicle (UAV) monitoring, digital twins, and optimization algorithms for emergency response. A model of a dual-container 110/10 kV station with interchangeable generator and storage modules has been developed. A novel System Resilience Improvement Index (RII) is proposed, which integrates recovery time, economic costs, the risk of repeated failures, and critical load availability. Scenario modeling of a double-tower collapse on a 110 kV transmission line, simulated with SimPy and NetworkX, demonstrated significant performance gains: average recovery time was reduced from 18.2 to 5.1 hours, direct costs fell from a baseline of 100% to 60%, repeated failures decreased from 35% to 12%, undelivered energy was reduced by a factor of 3.5, and the RII indicator increased by 58%. These results confirm the high effectiveness of the proposed modular station solution. It has been established that the efficiency of implementing modular stations for post-outage repairs can be increased by more than half. Potential limitations to widespread adoption are also identified, including significant financial costs, research and development requirements, logistical challenges (e.g., narrow roads or flood zones), as well as a lack of regulatory documentation and standards.

The concepts of thermal power and general energy systems are outlined. The priority areas for ensuring failure-free operation of facilities are identified. An analysis of the largest man-made accidents in Russia’s power sector over the past fifteen years is presented, using State District Power Plants (GRES) as a case study. Systemic challenges within the Russian energy infrastructure are highlighted. Specific technological solutions for streamlining processes and upgrading equipment to enhance safety at GRES are examined. Key factors influencing the safety and reliability of thermal power facilities has been assessed. Consideration is also given to the “green” transition concept. The engineering approaches employed at Rosatom State Corporation’s nuclear power plants are analyzed. The list of innovative technological solutions for nuclear power plants and the results of the implementation of the state program for modernizing thermal power plants are given. Directions for further improvement of nuclear energy systems are outlined, including promising areas for upgrading power equipment. The root causes of the most significant man-made accidents in Russia's energy systems from 2010 to 2024, successful power plant modernization solutions, current technological trends in energy equipment improvement, and development pathways for energy systems aimed at reducing technological hazards have been identified.

The operation of power oil-immersed transformers inevitably leads to the deterioration of their components. This creates a need for regular diagnostics and monitoring of the technical condition of both the transformers themselves and the associated power plant equipment. Optimizing the maintenance system for power oil-immersed transformers is a complex task, dependent on numerous factors and based on the principles of reliability theory, aging and restoration processes, and technical diagnostic methods.

The forecasting of the residual life of a power oil-immersed transformer, implemented in the developed software, is a key factor in decision-making regarding continued operation or the need for repair interventions. The development and enhancement of the system for assessing the technical condition of power transformers enables a comprehensive approach to technical condition assessment, allows for the determination of the limiting state of power transformers with long service lives to make informed decisions on the possibility of their further use or the need for decommissioning, and improves equipment reliability.

The refinement and increased effectiveness of the technical condition assessment system for power transformers allows: ensuring a comprehensive approach to analyzing technical condition, establishing the limiting state of power transformers with long service lives to make informed decisions regarding the possibility of their further operation or the expediency of decommissioning, as well as increasing operational reliability.

The developed approach to diagnostics and monitoring contributes to more accurate forecasting of the transformer's residual service life, an increase in the time between repairs, enhanced operational reliability, and a reduction in repair and maintenance costs.

In Russia, the need for comprehensive development of information modeling technologies and automation of industrial processes is recognized at the federal level. This is especially relevant for large and high-tech industries in development, such as nuclear energy. Rosenergoatom JSC has approved plans to increase electric capacity through the construction of new NPP units. The implementation of large-scale infrastructure and energy projects requires fundamentally new approaches to the organizing construction and installation works (CIW). As a solution, integrated automation based on robotic complexes and information modeling technologies (IMT) is proposed. The proposed technological solution is based on several interrelated elements: digital design and as-built engineering models of the facility (DDIM and DEIM), as well as software and hardware complexes (SHC), including ground-based (walking robots) and aerial (drones) robotic platforms. These systems are integrated into a single loop that provides autonomous highresolution data collection (laser scanning, photographic documentation), integration of data into digital models and automatic fact-versus-actual analysis to identify deviations from the project. The successful application of this system has been demonstrated in the construction of the Baltic Chemical Complex. Robotic complexes have proven their effectiveness by identifying critical nonconformances at an early stage. It is proposed to extend the experience gained to the construction of NPP units, yielding a range of economic, technical, organizational and other benefits.

One of the promising directions for improving the efficiency of condensing heat exchangers is the intensification of heat transfer through the transition from the traditional film mode to the dropwise condensation mode, in which condensate is formed as separate droplets rather than a continuous film, which virtually eliminates thermal resistance in the form of a condensate film. As a result, heat exchange processes are intensified during condensation of water vapor.

In this paper, experimental studies were conducted to determine the effect of modifying heat exchange surfaces on the efficiency of a condensing heat exchanger. The modification was carried out by forming a film of a surfactant, octadecylamine, on the heat exchange surface, resulting in the hydrophobization of the surface.

A laboratory heat exchanger prototype was developed and manufactured for conducting experimental research on the territory of CHPP-16 of the Mosenergo branch of the Federal State Budgetary Educational Institution of Higher Professional Education NRU MEI. Analysis of the research results has shown that modifying heat exchange surfaces using octadecylamine is a technologically sound solution for intensifying heat exchange processes in condensing heat exchangers. As a result of modifying the steel tubes of the laboratory heat exchanger prototype, the contact angle increased from 88° for the original surface to 110°. The transition to the dropwise condensation mode resulted in an increase in the thermal power of the laboratory heat exchanger prototype up to 61.5% compared to the original surface under identical operating conditions.

The article presents the results of an experimental study on changes in the free surface level of a high-temperature lead coolant during the bubbling of argon and hydrogen through nozzles of various geometries in a stationary tank depending on the duration of gas injection. The experimental procedure consisted of multiple stages, each involving injecting gas into the liquid lead bulk using a compressor for 3 hours, with the level measurements taken hourly, which was followed by a one-hour period without bubbling, after which the level was measured again. Experiments were conducted with three nozzle types and two different gases: argon and hydrogen. The control volume of lead was also varied during the experiments. The results indicate that with relatively small volumes of lead coolant, no significant change in the free surface level occurs due to gas saturation of the coolant. This effect was absent for both argon and hydrogen — gases used in nuclear reactors with heavy liquid metal coolants. Furthermore, varying the gas injection method by using different nozzle geometries also failed to produce a significant change in the free surface height. The findings of this study may be useful for designers of reactor systems employing heavy liquid metal coolants with a free surface. Subsequent work may involve experiments with larger lead volumes, the use of more advanced level measurement techniques, and monitoring the flow rate of gas injected into the lead coolant.

The operation of power units at boiler-turbine parameters beyond standard supercritical levels necessitates highly intensive cooling systems. This study focuses on development and investigation of a boiling coolant system for advanced steam turbines operating under these extreme conditions. A capillary-porous cooling system, designed for the hollow section of nozzle blades and operating on a heat pipe principle enhanced with an additional mass potential, is presented. Experimental setups were developed to optically investigate the dynamics of vapor and liquid phase formation. The research employed holographic interferometry using an LG-38 helium-neon laser-based interferometer to study vapor generation. Process visualization was achieved through high-speed cinematography with an SKS-1M camera, supplemented by photography and filming using Zenit and RFK-5M still cameras, and Krasnogorsk and Kiev-16C movie cameras. The initial stage of vapor bubble nucleation and the subsequent dynamics of growth and collapse within the capillary-porous structure were examined. The ability to partition the total energy during bubble nucleation was identified as a critical factor for combating erosion and cavitation. The paper presents chronograms and holographic interferograms of heat transfer processes for various mesh structures, thermal loads, and liquid excess levels, including calculations of internal boiling characteristics and liquid droplet ejection. An emergency scenario was simulated by reducing the coolant flow to a minimum. The proposed cooling system is applicable to the design of new turbine configurations for ultrasupercritical operations. A key finding of interest is the relationship between the limiting state of the capillary-porous coating and the heat transfer crisis during regime shifts, which paves the way for developing real-time diagnostic systems for these structures.

The paper examines improvements of high-speed protection systems for transmission lines in 6 – 10 kV distribution networks, particularly current cut-offs, focusing on ensuring their sensitivity and selectivity. Traditional methods for setting current cut-offs — based on accounting for the short-circuit current at high-voltage terminals either before the nearest transformer or before the most powerful transformer in the line — are critically analyzed. It is shown that these methods have drawbacks: in the first case, the protected zone length is minimal; in the second case, when the transformer is located at the end of the line, the protection zone is maximal, but when it is connected at the beginning of the line, the zone is minimal, which significantly reduces protection effectiveness. As a solution, a universal setting method is proposed, based on accounting for the three-phase short-circuit current before the transformer located at the end of the protected line. This approach increases the length of the protected zone and enhances protection sensitivity regardless of transformer connection location. Special attention is paid to the practical implementation of the proposed method and its advantages over traditional solutions. Possible cases of coordinating current cut-offs using the proposed setting method with fuses protecting transformers of different ratings are also considered. The research results have significant practical value for designing and operating relay protection in complex network configurations with numerous transformer substations. The proposed solutions enable optimization of high-speed protection systems without compromising selectivity and reliability.