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Methods of increasing the energy efficiency of micro-hydroelectric power plants are considered in the work. A new hybrid concept of building a control system is proposed, which combines classical control laws and fuzzy logic. This makes it possible to improve the quality of the regulation of the parameters of the generated electricity regardless of changes in network operation modes and external conditions. It is shown that the use of hybrid filters will allow to increase the electromagnetic compatibility and, as a result, the energy efficiency of the system as a whole. References 12, figures 3. [ABSTRACT FROM AUTHOR]

Problem. The increasing popularity of electric cars worldwide is also seen in Ukraine, leading to a growing need for more charging stations. Studies show that 80% of electric car charging happens at home. This home charging usually occurs either through the standard AC power grid or through dedicated AC charging stations. This raises concerns about the safety of these charging stations and their potential interference with other electrical and electronic devices nearby. Goal. The goal of this work is to determine the main electromagnetic parameters in the connection cable during the operation of an AC electric vehicle charging station. Methodology. To achieve this goal, it is necessary to study the electromagnetic parameters of the charging station connection cable when AC flows through it and to identify the electromagnetic parameters of the interference that occurs during the operation of the AC charging station. Classical electrophysical methods for calculating electric and magnetic fields and methods for determining the parameters of quadrupoles from the theoretical foundations of electrical engineering are used. Results. The main electromagnetic parameters in the connection cable during the operation of the AC electric vehicle charging station have been identified. Formulas for calculating the current strength and magnetic field strength have been obtained. Originality. New formulas for calculating the electromotive force of interference generated during the operation of the electric vehicle charging station, when AC flows through the charging cable, have been developed. Parameters of capacitive and magnetic coupling between two conductors in a common bundle have been identified. Formulas for determining the current induced by these parasitic connections have been obtained. Practical value. Accurately determining and calculating these parameters allows for the design of a charging station that operates reliably over a long period without causing interference with nearby electrical and electronic systems or devices.

Buildings consume significant amounts of energy and resources at all stages of their life cycle, causing a huge impact on the environment. Life cycle energy analysis is a holistic approach to assessing the design energy efficiency of buildings. Although new construction involves the energy-efficient, sustainable buildings, the energy demand in the construction sector will increase due to the ever-increasing demand for housing. Therefore, housing construction has significant potential for energy saving and potential for further research. The aim of the article is an energy analysis of the life cycle of buildings to formulate a strategic framework for reducing the energy footprint of the construction sector. The article examines energy-efficient solutions at the stage of selection of building systems for the construction of external wall structures. The evaluation criteria were the indicators of heat transfer resistance, embodied energy and carbon dioxide emissions from the production of building materials. It is shown that in terms of thermal and technical indicators, structures with facade thermal insulation meet the requirements of the current legislation. Comparison of embodied energy indicators showed that for a wall structure made of solid bricks, this figure is 2.0–2.7 times higher than for walls using energy-efficient building materials, which is due to the high density of ceramic bricks and significant energy consumption for their firing. For aerated concrete walls, the value of embodied energy is 769 and 1019 MJ, and the embodied carbon dioxide value is 54 and 69 kg/m2 when using expanded polystyrene and mineral wool, respectively. Life cycle energy assessment provides a strategic framework for reducing energy demand in the construction sector for practical implementation by developers. Prospects for further research in this direction are to determine the embodied energy of the proposed solutions, taking into account the durability of building materials.

The subject of research in this article is the forecasting of energy consumption when computing distributed tasks on computer networks built on the basis of server solutions and distributed systems based on personal smartphones. The goal of this study was to create a universal computing energy cost prediction model that can be applied to both traditional and mobile cloud systems. Tasks: conduct an analysis of energy-saving approaches and technologies used to calculate data; consider computer system models and actions with them, namely: model of distributed job, model of distributed computing system, model of distribution strategy; develop a common and uniform dynamic method of forecasting spent energy with a focus on heterogeneous systems; conduct a study of the proposed approach on stationary and mobile devices. The obtained results include. The results of the experimental measurement of the energy consumption of mobile digital systems and stationary ones are presented. The energy efficiency of computing on GPUs of a stationary device based on CUDA technology and GPUs on mobile devices based on Apple Metal technology was determined. Computation during the calculation of 600 frames on a distributed system from mobile devices with failure settings showed a consumption of 15320 joules of energy. Simulation of computing on a distributed system with stationary devices showed a consumption of 52806 joules of energy. This gives us 3,45 times the consumption benefit from computing on mobile devices. Forecasted consumption is also very accurate. Conclusions. The energy consumption assessment model proved to be quite effective. The results of the experiments show that the energy consumption estimation model takes into account the features of the hardware platform where data processing is performed. Computation of data on the GPU of stationary devices loses energy efficiency to a similar implementation on the GPU of Apple Metal from mobile devices. Therefore, the presented results demonstrate the rationality of using mobile graphics processors for energy-efficient information processing.

The subject of this 6G communication system research is expected to form a hyper-connected network in which various electronic devices can connect continuously without interruption. Several technologies have been built to support 6G communication systems, such as intelligent reflecting surface (IRS). An IRS is a reflector equipped with several two-dimensional passive elements that perform a phase shift by each element, which can reflect electromagnetic (EM) waves coming from the base station (BS) to the user equipment (UE), which is controlled via a controller to increase the signal strength at the UE and overcome poor propagation conditions. IRS can be placed anywhere, such as on a wall or on the roof of a building. The aim of the IRS research is expected to reduce the energy consumption and increase the spectral efficiency of wireless networks using artificial intelligence (AI) with low costs, energy savings, no thermal noise, and fairly small levels of interference. The objective of this research is to evaluate and analyze the energy efficiency (EE), including the achievable rate (AR) and signal-to-noise ratio (SNR), by applying the IRS architecture in a 6G communications system, which uses an operating frequency of 95 GHz and a bandwidth of 800 MHz. Then, the method was based on computer simulation using the Matlab software. In this paper, 6G communication system modeling was proposed. This model uses an urban microcell (Umi) that consists of one base station (BS) with multiple antennas, varying the number of IRS reflecting elements and one user. In this research, AR, SNR, and EE, using the frequency of 95 GHz and simulations with MATLAB@2021a software. The results show that the number of elements as many as 400 is 39% more optimal than the number of elements as many as 40 for the AR results. The SNR results without electromagnetic interference (EMI) are higher than SNR values affected by EMI with SNR results of 100 dBm, and the number of reflecting elements is directly proportional to the SNR results. For 800 elements, the EE value is 26% higher than for 40 elements. Conclusions. The application of IRS in 6G communication systems can increase the AR, SNR, and EE.

The results of a study of the energy efficiency of lighting installations of residential buildings and buildings of social and cultural purpose are given, and based on a technical and economic comparison of four options of lighting systems: with incandescent lamps, fluorescent lamps, compact fluorescent lamps and LED lamps, a quantitative assessment of lighting costs is given. A mathematical model of specific discounted costs was developed, which made it possible to take into account changes in lighting operating conditions over time, and the presentation of research results in relative units gave them a generalized appearance. Conclusions were drawn and recommendations for their application were given. Ref. 9, fig. 2.

A microwave-convective dryer for seed grain is considered as an effective drying system that allows reducing energy consumption. It is emphasized that for optimal design and cost-effective operation, as well as proper observance of optimal storage conditions for agricultural products, in particular grain products, it is advisable to use microwave heating with simultaneous blowing of air through the layer and to ensure utilization of air heat from the magnetron cooling system. It was determined that one of the main problems of using a microwave field for processing dense layers of grain is to ensure sufficient uniformity of the distribution of the microwave field. It is emphasized that the use of horn-type waveguides makes it possible to effectively irradiate grain with microwave energy. The scheme of the installation for microwave-convective grain drying is proposed, in which horn antennas are proposed as waveguides, closed with fluoroplastic plates to prevent water vapor from entering the working chamber to the waveguide. The calculations of the cooling system of the anode blocks of magnetrons and the calculation of the grain preheating chamber are presented. The heating medium is air blown through the layer in a horizontal direction at a filtration speed of 0.14 m/s. Based on the calculation of the working chamber of a microwave-convective dryer with a dense layer moving with a flow rate of G = 1,25·10-2 kg/s, the power consumed from the network by magnetrons, taking into account the efficiency of the microwave chamber, and the appropriate number of magnetrons are determined. At the drying rate N = 5,8·10-5 с -1 and using three magnetrons with a total power of 3 kW, the specific consumption per kilogram of evaporated moisture will be 5.3 MJ/kg. The use of a heat recovery system in the preheating chamber reduces energy consumption by 1.3 times. [ABSTRACT FROM AUTHOR]

The work is aimed at improving thermomechanical compressors designed to provide recondensation systems of cryogenic liquids. A promising field of use of thermocompressors can be the river tanker fleet designed for the transportation of cryogenic products, for example, liquefied gas. High-pressure throttle cycles are usually used in gas recondensation refrigeration units. Known schemes of liquefied natural gas recondensers in tanks of medium and small capacity based on single-stage cryogenic gas machines (CGM). They implement the reverse Stirling cycle, and the working medium is helium. The resource of single-stage CGM Stirling is limited. In addition, they do not exclude the leakage of helium due to the sealing of the compressor piston. Promising gas coolers are Gifford cryogenerators with a remote compressor. Their advantage is the reduction of the number of moving nodes and points of potential refrigerant (helium) leakage. The use of Gifford coolers allows utilization of low-temperature heat by thermome-chanical compression of the working fluid. The principle of operation of thermomechanical compressor units is based on the consumption of thermal energy to compress gases and mechanical energy to drive the compressor itself. It is proposed to use the energy resources of cold and heated streams on LNG tankers or LNG bunkering vessels. The low-temperature flow is vaporized gas taken from the tank in the form of main engine fuel or formed in the bunkering process. The warm source can be outboard water or engine exhaust gases. The introduction into practice of a new type of coolers based on the combined use of thermocompressors and gas cryogenerators will make it possible to increase the period of undrained storage of low-temperature liquids and reduce the volume of potential emissions. [ABSTRACT FROM AUTHOR]

In order to achieve the goal of the European Climate Law of the European Union to reduce greenhouse gas emissions by 55% by 2030, the EU Commission proposes changes to European energy and climate legislation. These changes include 16 initial legislative and strategic proposals related to energy and climate legislation, which are discussed in this article. A comparative analysis of existing legal provisions with the EU Commission's proposals has been conducted, identifying the differences proposed for adoption in updated regulatory acts. It is found that the proposed changes aim to strengthen existing climate and energy legislative acts by primarily making changes to their objectives, scope, and structure. The changes also concern EU emissions trading system, effort sharing system between the Member States, energy taxation, energy efficiency, and the promotion of renewable energy sources. The reform package includes new instruments such as the introduction of a second emissions trading system for the buildings and transport sectors, the use of the Carbon Border Adjustment Mechanism, and the establishment of the Social Climate Fund. The EU Commission actively utilizes a combination of legislative provisions and policy instruments based on pricing. However, the number and nature of conflicts that may arise between the proposed measures are not yet fully understood. It is currently challenging to assess the possibility of achieving greenhouse gas emission reductions in the transport and buildings sectors by 2030 solely based on the proposed instruments. The issue of ambitious targets in the context of the shortened timeframe until 2030 also presents challenges in achieving specific goals within defined time intervals. [ABSTRACT FROM AUTHOR]

Purpose. The research aims to analyze dynamic energy modeling of buildings using EnergyPlus and DesignBuilder software. The primary goal is to assess the energy efficiency, indoor air quality, and energy balance of buildings, taking into account various aspects such as ventilation and dynamic changes in temperature and humidity. Methodology. EnergyPlus and DesignBuilder software were utilized to create detailed dynamic models of buildings. Special attention was given to modeling ventilation and studying the energy balance. Various ventilation modeling algorithms were compared to determine their impact on energy efficiency. Findings. Energy flows in buildings based on dynamic energy balances for the heating period were investigated. A detailed analysis of the influence of ventilation on dynamic energy balances in the studied residential building room was conducted. Originality. This research offers a new perspective on dynamic energy modeling of buildings, expanding knowledge in this field by focusing on ventilation and energy balance aspects. The results contribute significantly to the development of approaches to improve energy efficiency, creating new opportunities for practical applications in engineering design and building operation. Practical value. The obtained results are an important contribution for engineers and designers developing strategies to reduce energy consumption and optimize energy use in buildings. The research can serve as a guide for the practical implementation of dynamic modeling in the planning and operation of buildings to achieve optimal energy efficiency. [ABSTRACT FROM AUTHOR]

War conditions always pose a series of challenges for a country, including ensuring the security and efficiency of the energy system. In such circumstances, the development and improvement of the country's energy system become particularly important. One of the main tasks of the energy system in wartime is to ensure the provision of electricity for civilian and military needs. To achieve this, it is necessary to ensure the uninterrupted operation of power plants and power transmission networks, as well as to carry out timely repair work and equipment replacement. Additionally, it is important to en)sure the energy security of the country. War conditions may lead to a decrease in energy production, which can result in dependence on the import of energy resources. Therefore, the development of do)mestic energy and the use of renewable energy sources become especially relevant. It is also important to develop and implement new technologies in the energy system, which will reduce energy production costs and increase its efficiency. For example, the use of modern energy flow management systems and remote monitoring will ensure the optimal operation mode of the energy system. Ukraine has significant potential for the development of wind, solar, and hydro energy. One of the main directions for the development of domestic energy is increasing the number of installed wind and solar power plants. In particular, the Ukrainian government plans to increase the share of electricity production from wind and solar power plants to 25% of the total production volume by 2035. Another important direction for development is the modernization of existing hydroelectric power plants and the construction of new ones, which will increase the electricity production capacity using water energy. Ukraine also has potential for the development of bioenergy, including the use of biomass and agricultural waste for electricity and heat production. Overall, the development of domestic energy has significant potential to reduce Ukraine's dependence on imported energy resources, decrease emissions into the atmosphere, and improve the environmental situation in the country. Therefore, the development and improvement of the country's energy system in wartime are important tasks that will ensure uninterrupted functioning, increase efficiency, and provide energy security for the country. [ABSTRACT FROM AUTHOR]

Depletion of the world's fuel and energy resources, which causes an inevitable increase in energy prices, both on the world market and in Ukraine, has exacerbated the problem of the introduction of energysaving technologies and put research aimed at the effective use of renewable energy sources for the purposes of energy supply into a number of strategic tasks state. The paper analyzes existing heat supply systems and ways to increase the efficiency of using existing energy resources and reduce emissions of harmful substances into the environment. The expediency of a comprehensive approach to the implementation of energy-efficient technologies in the heat supply system, taking into account the peculiarities of the operating modes of buildings and engineering life support systems, is shown. Based on the analysis of existing mathematical models and methods of calculating the operating modes of various elements of the combined heat supply system using renewable energy sources (solar collectors, heat pumps, heat accumulators, etc.), mathematical models of the operating modes of the specified systems are given. On the example of a separate building of public purpose (educational building), the calculation of the operation modes of the microclimate engineering systems was carried out taking into account the operating modes of the building, and on the basis of the available pilot plant, a study of the operation of the combined heat supply system using renewable energy sources and the use of heat accumulators was carried out to coordinate the generation modes and heat consumption by the building. On the basis of the conducted research, the distribution of the shares of energy savings from each stage of modernization of microclimate engineering systems and general thermal modernization of the building using both external thermal insulation and internal shielding of massive walls was obtained. [ABSTRACT FROM AUTHOR]

During the dry season, some parts of Indonesia experience drought and a clean water crisis, resulting in scarcity and difficulty in drinking water. One of the solutions to solve this problem is to use an air-water harvester machine that produces water from the air. Since the intake air temperature affected the water yield, the article examined the relationship between the engine intake air temperature and the machine’s performance. The study aimed to determine the performance of the air-water harvester machine at various air intake temperatures. The research was carried out experimentally for a refrigerant working fluid R134a. The rotary-type 1/4 PK compressor was used to realize the research. The air temperatures entering the condensing unit varied between 30, 35, and 40 °C. The results showed that the highest average water mass obtained was 0.34 kg at a temperature variation of 30 °C. The highest total heat absorbed by the condensing unit from the air of 184 W occurred at a temperature variation of 40 °C. Overall, an increase in the air intake temperatures allowed for a decrease in the performance of the air-water harvester machine by more than 5 %.

The paper presents a non-inductive broadband energy-efficient active balun based on a differential pair, intended for use in the input block of a frequency divider for 22nm technology. The developed device can operate in the frequency range from 2 GHz to 60 GHz with a supply voltage of 0.8 V and consume less than 3 mA. The special feature of the developed active balun is that it does not have inductive components, which reduces its size and signal loss. Amplitude of the output signal in working frequency range is from 450 mV to 200 mV. Signal gain in the range from 1-60 GHz varies from -10 dB up to 4 dB. The size of the circuit on the chip is 48x34 um. The device allows you to receive a stable signal at high data transfer rates and provides energy savings due to low current consumption.

Purpose. In this article, the authors aim to improve the mathematical model of train movement by adapting the model to determine the values of diesel power at the corresponding values of train acceleration and different modes of train operation. Based on the model, it is planned to build and analyze two-parameter dependencies of locomotive control during acceleration, which provide steady acceleration on different track profile slopes for different values of train weight, which will allow for more rational management of the locomotive fleet with strict adherence to the train schedule and minimal diesel fuel consumption for traction. Methodology. To achieve this goal, we used the method of system analysis, nonlinear programming, and numerical methods for solving differential equations of train motion, taking into account that the integration of the equation of train motion can be carried out by path, time, and speed, depending on the initially set task in traction calculations. Calculations were performed for different modes and phases of train operation. Findings. To analyze the results, we compared the obtained traction calculations, such as technical speed, travel time, and fuel consumption. To solve the problem of traction calculations, we chose the Maple software package, which allowed us not only to numerically evaluate the results of solving the two-parameter mathematical model, but also to graphically and visually, which greatly simplifies their perception. The obtained results of the calculations indicate a decrease in energy consumption. Originality. The model of train movement has been further developed, taking into account the adaptation to determine the values of diesel power consumption in the case of steady-state values of train acceleration depending on the weight of the train and the slopes of the track profile. Practical value. The expediency of the study is to save energy resources, in particular diesel fuel, for train traction and allows more accurate adherence to the train schedule, which, in turn, affects traffic safety in general.

The approach to solving the applied problem of modernization of the 300 MW series power units produced by JSC "Ukrainian Energy Machines" by converting them from supercritical to ultra-supercritical steam parameters, provided that regenerative feed water heating system is preserved as much as possible, which will lead to an increase in the energy efficiency of the TPP with minimal conversion, is analyzed in the paper. The conversion of the K-300-240-2 power unit to the parameters of fresh steam 650 °C/30 MPa and intermediate superheated steam 650 °C/7 MPa, determined as optimal as a result of previous studies, can be carried out by completely replacing the high-pressure cylinder of the existing unit for a new high-pressure cylinder with ultra-supercritical steam parameters and superstructure with an additional intermediate-pressure cylinder while fully preserving the parameters and designs of the intermediate- and low-pressure output parts. Two options for modernization of the 300 MW series power unit thermal circuit structure were considered, and the scale of conversion of the regenerative feed water heating system was evaluated. In the first option of the thermal scheme, the 1st steam selection is organized from the cold threads of the modernized high-pressure cylinder with ultra-supercritical steam parameters, and the 2nd one – from the cold threads of the additional intermediate-pressure cylinder. In this case, two high-pressure heaters and a turbo drive of the feed pump are subject to replacement. The disadvantage of this option is that due to a significant increase in steam parameters, it is impossible to choose high-pressure heaters from the existing model range, and a new design must be developed. The electrical efficiency for this modernization option increases from 36.5% (the initial thermal circuit of the K-300-240-2 turbine) to 42.5%. In the second option, it is proposed to install an additional turbine with a capacity of 3 MW, to the input of which a steam from cold threads of the high-pressure cylinder with ultra-supercritical steam parameters is supplied with a loss equal to the sum of the 1st and 2nd selections of the original version of the turbine, on the same shaft with a turbo drive of the feed pump for the sake of preserving the existing high-pressure heater. The steam from the additional turbine selections goes to high-pressure heaters HPH9 and HPH8 with parameters corresponding to the output data of the existing turbine. Taking this into account, high-pressure heaters will not be replaceable. In addition, the power of the additional turbine is sufficient to ensure the operation of the feed pump together with the turbo drive of the feed pump to obtain a water pressure of 34 MPa. In view of this, the turbo drive of the feed pump also remains unchanged, except for the additional turbine installation. The electrical efficiency for the second option of the modernization scheme of the K-300-240-2 power unit is 42.4%. It was determined that the payback period of the modernization according to the first option is 5 years, taking into account the modernization of the boiler unit, and according to the second one – 4.5 years. It is proposed to choose the option of the thermal scheme with an additional turbine, since in this case it is possible to modernize the K-300-240-2 power unit with the maximum possible preservation of the regenerative feed water heating system while increasing its energy efficiency by almost 14%.

Objectives Adaptations to digitalization and climate change of all aspects of society are important issues of innovation management at the local and regional levels. The paper demonstrates: 1) the components of smart specialization in order to achieve municipalities and regions strategy goals; 2) the use of the mechanism of smart specialization to realize the entrepreneurial potential of the regional economy; 3) the introduction of smart specialization for the innovative development of the Ukrainian municipalities based on the European experience; 4) the indicators of building resilience of municipalities and regions innovative management to smart specialization. Material and methods Combination of dialectical approach to the knowledge of the components of smart specialisation and the methods of induction, deduction for the realisation of the entrepreneurial potential of the regional economy based on cross-industry clustering became the basis for the development of recommendations for municipalities Results Extending the sustainability of innovative municipal and regional governance to smart specialisation is to take into account the importance of using the main postulates of the smart specialisation mechanism to realise the innovation potential of the regional economy. Conclusions The priority directions of the agro-energy cluster model should be the establishment of a cluster model of "Government-Business-Science-Education" interaction. In order to achieve this goal, scientists from the Western Ukrainian National University justified and developed the Programme for Supporting Innovation in Areas of Smart Specialisation in the Ternopil Region for 2020-2023, which aims to implement innovative approaches to capacity building of the regional economy within the framework of smart, sustainable and comprehensive development.

In the process of analyzing the methods, numerous results were obtained. On the basis of which it can be concluded that the results of calculations carried out using the method of maximum likelihood became the closest to the actual values. However, it is important to note that these results turned out to be very close to the results obtained when determining the average value of the data set. The main advantage of this definition is ease of implementation. Since the experiments were conducted on the basis of a relatively small amount of initial data, it is impossible to consider that the determination of the average value is the most appropriate for its implementation. The conclusion is suggested that there is a need to conduct an analysis based on a larger amount of initial data. And also, using other methods of finding the most reliable energy balances. The possibility of constructing maximum likelihood graphs when assessing the quality of energy balance indicators and directions of possible use of this method in tasks were considered. Ref. 4, figure, tables 5.

Modern heat and power plants (HPPs) face numerous challenges related to energy efficiency, the integration of renew-able energy sources, and environmental sustainability. The article examines the possibilities and prospects for the de-velopment of HPPs taking into account current trends and challenges. The main directions of HPP development include the integration of renewable energy sources (RES), the decentraliza-tion of energy systems, a focus on environmental sustainability, and the development of legislative and regulatory frameworks. These measures will contribute to the sustainable development of the energy infrastructure, ensuring en-ergy security, and improving environmental quality. Bibl.7, fig. 4, table.

The article examines the current state of development of the alternative energy market in Ukraine. An analysis of the energy market of Ukraine was made and the main factors stimulating the development of alternative energy were determined. These factors include legislative, economic, technological, administrative, geographic, and informational psychological factors. Changes in legislation related to the use of renewable energy sources are analyzed. A plan for the development of renewable energy sources in Ukraine is being considered. Today, most countries are trying to change their development scenarios to meet the ever-increasing energy needs. They do this by introducing new policies and focusing on alternative energy and energy efficiency issues. The transformation of energy markets is an important manifestation of modern energy trends. In this context, the achievements made within the framework of the Third Energy Package of the European Union regarding the creation of the European Union energy market should be particularly important. The analysis of the consequences of the transformation of energy markets in accordance with the Third Energy Package of the European Union allows to determine the main features and trends of the development of modern energy and to form connections between the subjects of the energy market in the next 10-20 years. All European countries have set targets for renewable energy. The European Union aims to become the world’s first climate-neutral continent by 2050.To achieve this goal, the European Union has launched its most ambitious package of measures, the European Green Deal, which aims to help people and companies in Europe achieve a sustainable green transition. In the light of the current pandemic, growing competition, globalization and ongoing European integration, research into the development of alternative energy is particularly important for Ukraine. Changes to the «green tariff» for wind and solar energy are presented. The paper shows that modern technological trends and improvement of energy efficiency and energy security of the country require changes in electricity production and are important for the country as a whole. [ABSTRACT FROM AUTHOR]

The main results of reports at the "Solar Energy" section were considered and summarized, in particular, one of the areas of solar energy - photoenergy. Specialists from Ukraine, Poland, the Czech Republic and the Republic of Uzbekistan took part in the work of the section in this area. A total of 22 reports were presented, which related to the issues of increasing the energy efficiency and reliability of the operation of solar power plants, the peculiarities of the operation of solar autonomous power plants and installations, new technologies for the production of photo modules, etc. For the most part, the reports focused on the creation and operation of energy-efficient and reliable solar power plants. [ABSTRACT FROM AUTHOR]

Pumping equipment consumes about 20 % of the electrical energy produced by humankind. A significant, even drastic, reduction in the weight and size indicators of pumping equipment leads to a decrease in the cost price and, therefore, competitiveness of such products in the market. Simultaneously, it makes it possible to use more valuable and high-quality construction materials and technologies that improve the reliability of equipment and its energy efficiency, which in turn is a clear step in solving many UN Sustainable Development Goals (SDGs). According to the research results, it was proved that by increasing the frequency of the drive, it is possible to reduce the mass and size indicators of the submersible pump for the needs of the critical infrastructure sector by reducing the number of stages. Mainly, the amplitudes of oscillations near the rotation frequency are 12–22 % and do not exceed 35 % of the gaps in the seals, as required by the available international standards to ensure the guaranteed vibration reliability of the pump. Overall, using a bearingless support design will significantly increase the reliability of the developed pump.

Purpose. Increasing the level of safety and reducing the cost of rolling stock maintenance is an urgent problem for Ukrainian railways today. Existing test benches for auxiliary machines are usually built according to the scheme with direct loading of the tested electric machine and do not meet modern requirements for the quality and energy efficiency of testing. In this regard, there is a need to design energy-efficient test benches for testing auxiliary machines of electric rolling stock. Methodology. To achieve this goal, we used an analytical method of research to determine the optimal structure of the test bench. The paper considers the voltage balance diagram in the mutual load system. Separately, the calculations are presented, on the basis of which the design diagrams of the electrical and mechanical parts of the test bench are constructed, and the conditions for covering all losses in the mutual load system are determined using the design diagrams. Findings. In the course of the research, the power balance equation in the mutual load system was obtained. On the basis of the equations, a model of a mutual load system with coverage of all losses from a single source of mechanical power was built. The main advantage of the developed model is that it can be implemented both by numerical calculations using composite systems of equations and by object-oriented programming in specialized software systems. Originality. A rational scheme for testing auxiliary machines with the coverage of losses from a single source of mechanical power is proposed. The use of a single power source can significantly reduce the additional consumption of electrical energy due to the more efficient use of auxiliary equipment, in particular, a mechanical power source. Practical value. Based on the results obtained, it is possible to determine the parameters of the scheme for testing auxiliary machines at the design stage of the test bench. Implementation of the research results at auxiliary machine repair enterprises will reduce electricity consumption for post-repair testing due to the higher energy efficiency of the test scheme.

The sustainable development paradigm includes the most efficient material and energy resources using in production processes. One of the ways to achieve this goal is creating the effective automated control systems. At the same time, such systems effective functioning is impossible without adequate mathematical models for control objects. Thus, the actual task of this study is to create the control object – a spray dryer -model-, which could be used in the control system. It was established that one of the main devices in the sodium tripolyphosphate production is a spray dryer in which the aqueous salts suspension is dried by flue gases. The obtained powdery product which is fed into the calcination furnace. The work investigated convective drying, where the material is in direct contact with the drying agent – furnace gas. To drying process control by the drying agent temperature. The existing works analysis showed that the mathematical model developing process of a spray dryer requires in-depth research into the physical nature of processes which taking object's operation’s various factors into account. The object presentation can be carried out with different approaches taking into account various important production factors, but at the same time it should be as close as possible to the nature of process. The development of the spray drying process model is carried out for regulation the moisture at the finished product. The beginning of the research is the structural and parametric diagram creation of a spray dryer taking into account all input and output values which allow to determine the control disturbance channels. A material balance based on the moisture and loose matter amount and a gas environment heat balance is compiled. The transfer functions component calculation is carried out using the Kramer method. The presented results of the research make it possible to build and analyse the spray dryer mathematical model taking into account the requirements for the substance moisture content be dried and the control process analysis by the drying agent temperature changing. The transient characteristics of the spray dryer by the disturbance and control channels, which are calculated and presented in the research make it possible to compare the control object behaviour with and without taking heat loss into the environment the assumptions into account.

The article is devoted to research and comparison of approaches to ensuring energy security in the European Union (EU) and Ukraine. The article analyzes the main aspects of energy security, such as ensuring energy independence, stability and sustainability of the supply of energy resources, the development of energy efficiency and the use of renewable energy sources, integration into a single energy space, as well as the challenges faced by both sides. The article highlights similarities and differences in approaches to ensuring energy security. Among the common aspects is the recognition of the importance of energy security and the significant attention paid to it by both parties. Both sides are also working on diversifying supply sources and improving energy efficiency. At the same time, there are differences in the development of energy infrastructure and access to resources, where the EU has a developed and diversified system, and Ukraine faces challenges and limitations. The article examines the prospects for the development of the energy sector in both contexts. The EU aims to ensure a stable, stable and sustainable supply of energy resources through the development of a single energy market and cooperation with other countries. Ukraine also has the potential to develop its energy sector, particularly in the field of renewable energy, which can contribute to reducing dependence on imports and ensure a stable and sustainable energy supply. Ukraine's integration into the single energy space of the EU and support and investment from the EU for the development of Ukraine's energy sector are considered important. The article also provides the necessary steps to ensure energy security in Ukraine. Among them, it is worth highlighting the modernization of the energy system, cooperation with the EU and other countries, diversification of supply, improvement of energy infrastructure, increasing energy awareness of the population and harmonization of legislation with European standards. Different research methods were used to obtain reasonable results. The article analyzed the official documents and strategies of the EU and Ukraine related to energy security. This analysis made it possible to identify the main principles and approaches used in each of the concepts. The article is supported by a review of current scientific research and publications on energy security that relate to the EU and Ukraine. This literature review identified key aspects and trends in the field. Deduction and induction methods were used for comparative analysis. The application of the deduction method made it possible to proceed from the general provisions and principles formulated in official documents to derive specific conclusions regarding energy security. With the help of the induction method, an analysis of specific facts and data was carried out, from which generalizations and the formulation of general conclusions were made. The general conclusion of the article is that both the European Union and Ukraine strive to ensure energy security, but their approaches and priorities may differ. The challenges facing both sides require continued effort and cooperation to achieve a sustainable and sustainable energy future.

The article analyzes the essence and directions of improving the energy efficiency of the national economy. It is noted that the leading role in this process is assigned to the economic mechanism, which should generally be recognized as an integrated system of means of influencing economic phenomena observed in the process of production, exchange, distribution and consumption of energy resources. It is emphasized that the most important indicator characterizing the efficiency of energy consumption at the macro-level is the energy intensity of gross domestic product (GDP), according to which Ukraine significantly lags behind many countries of the world. Therefore, one of the effective instruments to reduce the energy intensity of the State’s GDP is the use of tax incentives. The functional role of structural elements of the economic mechanism of energy efficiency is disclosed, which are manifested in the following: firstly, the leading place in the system of instruments for implementing energy-efficient policy is occupied by pricing for energy resources, which, unfortunately, is dominated by the cost methodology. Simultaneously, it is necessary to deprive enterprises of the domestic fuel and energy complex of the right to manipulate prices for their products; secondly, in order to implement the energy efficiency policy, it is necessary to form tariffs for energy resources based on the reimbursement of economically justified costs for their production, transportation and delivery to consumers; thirdly, the implementation of strategic goals for the development of energy saving requires significant investments, in particular, targeted loans to finance energy-saving technologies. The necessity of finding and developing new, more effective instruments of the economic mechanism for improving the energy efficiency of the national economy is proved.

The article is concerned with assessing and analyzing the energy efficiency of the Ukrainian economy by types of economic activity. The study analyzes the place of Ukraine among other countries according to international rankings (indices): the Energy Transition Index, the Trilemma Index of the World Energy Council (WEC), the International Energy Security Risk Index. It is found that Ukraine’s positions in international rankings determine a number of interrelated problems of energy, economic and environmental development of the country, among which one of the major ones is the high energy intensity of GDP. The dynamics of energy intensity of GDP in some countries of the world and in Ukraine is analyzed. A matrix for estimating the energy efficiency of economies of countries (groups of countries) according to the criteria of direction and intensity of changes and the level of energy intensity of GDP is proposed. It is examined what structural changes occurred in the energy sector and economy of Ukraine by the type of continuity of the production process and the level of energy intensity in the final consumption of fuel and energy resources (FER) and production output. The specific weight of characteristics of groups of foreign economic activity of Ukraine in the final consumption of FER and production output is analyzed. The related indices are computed and directions of structural shifts in foreign economic activity in final consumption of FER and production output are determined. A general characterization of consistency of structural shifts in final consumption of FER and production output due to foreign economic activity and their groups in Ukraine is formed. The carried out study allowed to determine that the high energy intensity of Ukraine’s GDP is a consequence of the peculiarities of the structure of the national economy, shifted towards more energy-intensive industries and technological lag of most sectors of the economy from the level of developed countries. It is determined that, in general, in the structure of the economy of Ukraine there were coordinated minor changes in the final consumption of FER and production output. However, in parts of the group of foreign economic activity related to industries with a continuous type of production process with high and medium energy intensity, there were significant uncoordinated negative structural changes both in the final consumption of FER and in production output. Some increase in energy efficiency of the national economy was caused by a reduction in production volumes in highly energy-intensive industries with a continuous production cycle. Thus, despite the high rate of decline in the energy intensity of GDP in Ukraine, its energy intensity remains one of the highest in the world (exceeding the world average by 2.1 times), which determines the unsatisfactory energy efficiency of the economy.

Purpose. Study of the dynamics of formation of biometric indicators, biomass yield and energy potential of sorghum varieties in the conditions of the Central Forest-Steppe of Ukraine. Methods. Field, laboratory and statistical methods were used. Five registered varieties of sorghum, viz: 'Huliver', 'Dovista', 'Zubr', 'Su' and 'Tsukrove' served as the object of research. The measurement of biometric indicators of plants, the calculation of biomass yield and energy potential were carried out in accordance with approved scientific and methodological recommendations. Results. The most rapid growth in height of sorghum was observed during the interphases of "seedling - leaf-tube formation and leaf-tube formation - flowering". At the end of the growing season, plants of the varieties 'Huliver' (237.2-245.1 cm), 'Tsukrove' (218.0-227.2 cm) and 'Dovista' (205.6-220.9 cm) were the tallest. 'Hulliver', 'Tsukrove' and 'Zubr' were characterized by the largest photosynthetic leaf area, they produced the largest biomass and were characterized by the highest energy efficiency of cultivation in terms of energy productivity (EPс equal to or greater than 60.0 GJ/ha) and energy efficiency coefficient (Kee equal to or greater than 4.0). Conclusions. The highest biomass yield by dry residue was found in the sorghum varieties 'Huliver' (15.4 t/ha), 'Tsukrove' (15.2 t/ha) and 'Zubr' (12.5 t/ha). The same varieties were characterized by high energy productivity (the difference between the energy stored in biomass and the energy used to produce it) - 65.3, 64.9 and 56.8 GJ/ha respectively, with a Kee value of 4.0 or more, which characterizes the average level of biomass production efficiency. [ABSTRACT FROM AUTHOR]

The paper presents the results of mathematical modeling of electric and thermal processes in graphitized wick (composite) and monolithic electrodes for DC steelmaking furnaces. Calculations were performed using the developed mathematical model based on the finite element method with introduction of a number of simplifications and assumptions. The model allows determination of the regularity of electric and thermal processes running in the electrodes. Distribution of current density, electric potential and temperature in composite electrodes was studied at application of different wick compositions with different ratios of their specific electric resistances and electrode resistances, which enables prediction of their performance at application in arc furnaces. Results of estimated calculations showed that wick electrodes have lower electric losses and their heating temperature than monolithic electrodes, making them more energy and resource efficient. 8 Ref., 8 Fig. [ABSTRACT FROM AUTHOR]

The article explores the issue of energy efficiency in the context of contemporary challenges such as resource scarcity, urbanizatio, and environmental regulations. Particular attention is devoted to the potential of the Internet of Things (IoT) for automation and optimization of energy consumption. In the backdrop of globalization and technological advancement, research on IoT as a tool for efficient energy resource utilization is identified as a promising avenue for exploration. Publications related to smart buildings in Ukraine are highlighted, focusing on their consumer role in electricity consumption and the potential of IoT for optimization. The study delves into the concept of "green" IoT, examining challenges and principles of energy efficiency specific to IoT devices. The analysis of additional research concerning IoT capabilities in the water supply sector and energy efficiency in the construction industry is provided. The paper aims to investigate the technology’s potential for reducing energy consumption. Principal research tasks include: analyzing the architecture of IoT for a better understanding of its structure and capabilities; studying key areas of IoT application in the sectors like construction and industry for energy conservation; outlining fundamental principles for IoT utilization in optimizing energy consumption. The architecture of IoT systems is studied in-depth to fully understand their structure and dynamics, playing a crucial role in maximizing their potential for energy conservation. The authors focus on investigating the areas where IoT finds application in energy conservation, understanding key spheres across various sectors, including construction, industry, and urban planning. Through detailed analysis of IoT architecture and its capabilities, the paper identifies four key principles for the effective use of IoT technology in the energy sector. These principles encompass setting specific energy goals, implementing technologies for monitoring and automation, data collection and analysis for consumption optimization, and evaluation of outcomes for further system improvement. The work emphasizes the role of IoT as a potent tool for enhancing energy efficiency and achieving global sustainable development goals. Overall, the paper seeks to contribute to existing knowledge about the capabilities of IoT in the context of energy conservation, prompting further discussion and research in this field. [ABSTRACT FROM AUTHOR]

Innovations are an essential part of business management in modern society. In addition to large enterprises and research and development centers, small and medium-sized enterprises also hide great innovative potential. Moreover, it is precisely the innovations that lead businesses to permanent growth and prosperity. In addition, from the point of view of Industry 4.0, innovation must be considered as an essential part of the functioning of a modern enterprise, regardless of its size. The article compares statistical indicators that capture enterprises’ innovative activity or inactivity in the Slovak Republic. Enterprises that want to define themselves as innovative should have a suitably prepared and functioning environment, while internal and external conditions are essential. However, it turns out that Slovakian companies have not created suitable conditions for innovation, and in the long term, their interest in innovation is declining. At the same time, because of the industrial revolution, many professions are also changing, and the demands for specific knowledge are not only growing for the newly created ones, but they will also require an active approach to changes, i.e., innovations. Companies must introduce an innovative approach in the education process itself, and as it shows, it will not be possible without a systemic approach.

The article highlights the experience of using 3D printing at automotive enterprises manufacturing automotive wiring. The primary attention was paid to optimizing technologies and modernizing equipment in 3D printing in production conditions. This helped to improve the printing quality at the enterprise and reduce energy consumption during mass printing of parts. The article aims at improving quality and reducing energy consumption during 3D printing in serial production conditions. The technique’s novelty consists of a complex of production optimizations combined into a production rack to improve 3D printing. During the research, negative factors affecting print quality and their elimination were analyzed. An experimental setup for 9 printers was created. As a result, ways to increase energy efficiency according to environmental standards were implemented under the mass production of 3D parts. Overall, the applied technology allowed for reducing the time for the development of new prototypes. This made it possible to reduce the produced parts cost and allowed for implementing urgent changes in manufacturing enterprises.

The problem of increasing the efficiency of individual heating systems is solved by using heat pumps based on a liquid-vapor ejector with the working fluid R718 (water). The research object was the working process of the liquid-vapor ejector, based on the principle of jet thermal compression. It involves the generation of vapor in the nozzle of the motive flow of the liquid-vapor ejector and does not require its supply from an external source. Schemes and descriptions of the traditional system and the proposed scheme were given. Their difference from the traditional ones was indicated according to the schematic solution and working cycle. The article compared the proposed schemes’ thermodynamic calculation with the working flow R718 and traditional heat pump systems with carried-out refrigerants R134a, R410a, and R32. As a result, the values of the thermodynamic parameters of all system components were obtained. The coefficients of performance (COP) for the traditional and proposed cycles were determined. Applying the new scheme made it possible to increase the COP by an average of 40 %. An exergy analysis assessed the expediency of implementing vacuum units based on liquid-vapor ejectors in individual heating systems. This made it possible to compare systems that use several types of energy (e.g., electrical, thermal) and to determine their efficiency with high accuracy. As a result of the exergy analysis, the value of the proposed scheme’s exergy efficiency was obtained.

The work analytically investigates a new recuperative-transformer system with subcooling of the recirculation flow of furnace cooling, which increases the heat-technological and energy efficiency of furnace units, expanding the technical and economic efficiency of industrial heat supply. The basis of the research is the conclusion that the application of heat pump technologies for energy saving in the production of building materials in rotating furnaces with the utilization of low-temperature gas-air flows is very promising. It is noted that the stabilization of the thermal mode of furnace cooling during the year is an important technical and economic task aimed at improving the thermal process and energy saving, primarily for the firing zone. An analytical study of the recuperative transformer system with subcooling of the recirculation flow was conducted. The equation of the heat balance of the heat extraction system of the gas-air circuit in the process of furnace cooling is presented. The transfer of heat absorbed from the surface of the furnace in recuperative heat exchangers, as well as in the evaporator of the thermotransformer circuit of the vapor compression heat pump is described. A generalized dependence was obtained for the heat flow of furnace cooling and a low-potential source in the gas-air circulation circuit of the heat supply system. The dependence for the real conversion factor is determined. A graphical interpretation of the dependence of the effective conversion factor on the ratio of the consumption of the heating medium and the heated medium is presented. It is emphasized that the results of the study of the rational interrelationship of the initial and mode parameters create a basis for the engineering development of the proposed heat supply systems based on the stabilizing cooling of the rotating furnace. [ABSTRACT FROM AUTHOR]

Human global anthropogenic influence forces the developers of household refrigeration equipment to reconsider their attitude towards absorption refrigeration devices (ARD). The working body of ARD consists of natural components – water-ammonia solution (WAS) with the addition of inert gas (hydrogen, helium or their mixture) and is absolutely environmentally safe – it has zero values of ozone-depleting potential and the potential of the "greenhouse" effect. Absorption refrigeration devices have a number of such unique qualities, such as: silence, high reliability and long service life, absence of vibration, magnetic and electric fields during operation; the possibility of using several sources of energy in one device – both electric and alternative; the possibility of working with low-quality energy sources, in particular, electric energy, in the range of network voltage 160...240 V. At the same time, ARDs have higher energy consumption compared to similar compression models. In this work, an attempt is made to analyze the energy characteristics in a wide range of regime parameters using the thermodynamic parameters of real ARDs obtained by various researchers. The developed method of thermodynamic calculation of a typical absorption refrigeration device, which is based on the results of experimental studies of typical real models, allows variant calculations for a wide range of operating parameters. It is shown that a decrease in the average evaporation temperature leads to an increase in heat loads on the ARD elements, i.e. freezers always have large weight and size characteristics, compared to refrigerating chambers of medium cold. The limitation of the maximum boiling temperature in the ARD generator was found, which is determined by the corrosion resistance of the wall material. It has been shown that ARDs of tropical design with a working pressure of 30 bar in the system require high energy consumption, compared to similar models for a temperate climate. [ABSTRACT FROM AUTHOR]

The article is concerned with assessing and analyzing the energy efficiency of the Ukrainian economy by types of economic activity. The study analyzes the place of Ukraine among other countries according to international rankings (indices): the Energy Transition Index, the Trilemma Index of the World Energy Council (WEC), the International Energy Security Risk Index. It is found that Ukraine’s positions in international rankings determine a number of interrelated problems of energy, economic and environmental development of the country, among which one of the major ones is the high energy intensity of GDP. The dynamics of energy intensity of GDP in some countries of the world and in Ukraine is analyzed. A matrix for estimating the energy efficiency of economies of countries (groups of countries) according to the criteria of direction and intensity of changes and the level of energy intensity of GDP is proposed. It is examined what structural changes occurred in the energy sector and economy of Ukraine by the type of continuity of the production process and the level of energy intensity in the final consumption of fuel and energy resources (FER) and production output. The specific weight of characteristics of groups of foreign economic activity of Ukraine in the final consumption of FER and production output is analyzed. The related indices are computed and directions of structural shifts in foreign economic activity in final consumption of FER and production output are determined. A general characterization of consistency of structural shifts in final consumption of FER and production output due to foreign economic activity and their groups in Ukraine is formed. The carried out study allowed to determine that the high energy intensity of Ukraine’s GDP is a consequence of the peculiarities of the structure of the national economy, shifted towards more energy-intensive industries and technological lag of most sectors of the economy from the level of developed countries. It is determined that, in general, in the structure of the economy of Ukraine there were coordinated minor changes in the final consumption of FER and production output. However, in parts of the group of foreign economic activity related to industries with a continuous type of production process with high and medium energy intensity, there were significant uncoordinated negative structural changes both in the final consumption of FER and in production output. Some increase in energy efficiency of the national economy was caused by a reduction in production volumes in highly energyintensive industries with a continuous production cycle. Thus, despite the high rate of decline in the energy intensity of GDP in Ukraine, its energy intensity remains one of the highest in the world (exceeding the world average by 2.1 times), which determines the unsatisfactory energy efficiency of the economy. [ABSTRACT FROM AUTHOR]

New coming environmental regulations from International Maritime Organization put each involved actor from ship manager, ship owner to cargo owner into a hard situation for a short time period to change the data collection process, to determine gups considering operating needs, to create an improvement plan according to specific requirements, needs, and goals. It is one more signal, in order to reach the sustainability goal, the industry digitalization process, and available efficient and effective use of technologies should be pushed forward. From cold chain digitalization, refrigeration system maintenance, and retrofitting processes, in particular, data science, process science, and data mining can be used. Refrigeration system retrofitting process modelling is presented by data mining technology. A lack of knowledge and investment in cold chain best practices and infrastructure lead to projects failing. Efficient, controlled, and smart Refrigeration is a challenge for the sustainable refrigeration sector. The global reefer transport market will expand up to 6% from 2020 to 2027 and it is vital for countries involved in military operations as well. The results of energy, exergy, and exergoeconomic analysis of different solutions intended for marine refrigeration transport, the cascade refrigeration system with R717-R744 refrigerants is presented. It was found that the optimum condensation temperature for the refrigerant of the high-temperature circuit is 40 °C, while the boiling temperature of the lower-temperature circuit is -50 °C. The temperature mode can be considered optimal ceteris paribus. The article provides an analysis of ejector refrigeration systems that can be used to improve the energy performance of marine refrigeration plants. It is a recommended issue to consider not only industrial requests but policies, and regulations in the force and in projects development status that can change an organization’s vision and aims of a strategic packet in own turn it can be affected a project budget change for labs, research institutions, shipyards.

Goal. Assessment of the influence of textural-structural and physical-mechanical characteristics of ferruginous quartzites in deep quarries of Kryvbas on the energy efficiency of production and enrichment of raw materials during its technological processing in the conditions of formation of an eco-industrial park. Methodology. The methodological basis of the research is a systematic approach to the problem of assessing the textural, structural and physical-mechanical characteristics of ferruginous quartzites and the problems of energy efficiency and enrichment of mineral raw materials in the regional consideration of the Kryvyi Rih iron ore basin. In accordance with the specifics of research aimed at achieving the tasks set and obtaining technological dependencies, the following methods were mainly used in the work: analytical, graphoanalytic and mathematical statistics. Results. Quantitative relationships of iron content depending on the physical and mechanical characteristics of quartzites and technological enrichment indicators are revealed. It is established that when forming ore flows in the quarry, it is necessary to take into account not only the iron content of general and magnetic, but also the physical and mechanical properties of types and grades of ores, their textural and structural features, the presence of harmful impurities and the granulometric composition of ore in the quarry, which significantly affect the efficiency of the enrichment process and its energy consumption. It is noted that the increase in energy efficiency is achieved by introducing reasonable management and technological measures, taking into account the influence of textural, structural and physical-mechanical characteristics of ferruginous quartzites in the quarry on the quality indicators of further processing of mineral raw materials at the ore processing plant. Scientific novelty. The dependencies and interrelations of natural-geological, physical-mechanical, technical, organizational and environmental factors, and their combined impact on the efficiency of technological processes of extraction and processing of ferruginous quartzites, provided that rational energy consumption is observed, are established. Practical significance. The results obtained are important and useful for determining the energy efficiency of enrichment processes in the iron ore industry in the context of persistent environmental deterioration, significant fluctuations in price characteristics in the iron ore raw material markets and difficult business conditions at mining enterprises due to the negative impact of previous non-cost-effective activities and quarantine restrictions due to the global pandemic in recent years.

Problem. The tendency to reduce Engine displacement, which has emerged in recent years in the global automotive industry, is due to the need to improve the environmental situation and energy efficiency of vehicles. Goal. The aim of the study is to increase the energy efficiency of vehicles by rationally reducing the maximum effective engine capacity. Methodology. In the paper authors used the method of partial accelerations implemented in a mobile registration and measurement complex, which allowed authors to obtain an improved formula for calculating aerodynamic drug. Experimental studies of car aerodynamics were also conducted. Results. In the study presents the results of the authors' research, which made it possible to prove the possibility of reducing the e internal combustion engine capacity while maintaining the specified maximum speed and the specified level of indicators of the car dynamic properties. Originality. The relationship between the use of maximum engine capacity and the relative change in the effective specific fuel consumption of a carburetor gasoline engine, with direct injection of gasoline and diesel were determined. Practical value. Calculations performed on the example of the ZAZ-1103 "Slavuta" car showed that a rational reduction in effective engine capacity allows to reduce fuel consumption by 9.5% for carburetor gasoline engine, and for an engine with direct injection of gasoline by 6.7 % and for diesel engines, by 20.3%.

The purpose of the article is to substantiate the feasibility of an integrated approach to the implementation of measures for the restoration and modernization of housing stock and heat supply objects. On the conditional example of heat supply of a heated quarter (which means a small number of residential buildings to be heated, a local boiler room and local distribution heat networks), various modernization options are considered: separate thermal modernization of buildings, modernization of heating networks, modernization of the boiler room, and options for simultaneous modernization of all elements of the chain: production-supply-consumption of heat energy (complex modernization of the heated district). It is proved that precisely a comprehensive modernization, which involves a simultaneous production, coordinated in terms of time and volumes, supply and consumption of heat, is an effective instrument for improving efficiency in the sphere of heat supply and heat consumption. The complexity of modernization in this example involves thermal modernization of buildings in the heated district (with a decrease in heat consumption by 40%) with the simultaneous modernization of heat transmission networks (with a decrease in heat loss when supplied from 20% to 5%) and modernization of the boiler room (with an increase in the efficiency quotient of boiler equipment from 88% to 93%). The implementation of such a project is economically feasible for all participants: consumers reduce the cost of paying for heat supply services by 49%, and the supplier and producer of heat with a slight (up to 6%) increase in heating tariffs provide break-even activities and receive a larger investment resource in the form of a larger amount of depreciation. At the national level, the proposed mass complex modernization of heated districts can almost halve the consumption of natural gas by municipal heat and power engineering and to the same extent reduce emissions of harmful substances into the atmosphere. In addition, it becomes possible to significantly reduce the amount of subsidies from the budget for the payment of housing and communal services by the population.

The expediency of conducting research in the direction of improving the energy efficiency of submersible induction motors due to the introduction of a set of tools for the design synthesis of their innovative designs was reasoned. Means of design synthesis of submersible induction motors of innovative designs are considered. The combination of which in the implementation of the design will allow to increase the level of improvement of submersible induction motors in accordance with the requirements for modern equipment, such as: reliability, energy efficiency, economy. The results of realization of the induction motor optimal design synthesis of the submersible pump of an innovative design on the basis of the ПЭДВ 2.8-140 motor by criterion of a maximum efficiency are resulted. Ref. 10, fig. 2, table.

The article notes that energy efficiency cannot simply be a vague and ambiguous concept that does not have accurate assessment methods. It should have clear measurements and evaluation methods. When the question arises as to measuring or evaluating, the lack of a clear definition of energy efficiency can cause the results to differ and it will be difficult to compare them depending on the needs or objectives. So the need to develop an accurate and unified definition of energy efficiency, as well as its classification and development of measurement methods is highlighted. It is emphasized that highly developed countries of the world have significant experience in achieving a high level of energy efficiency of national economies, but they also do not currently have developed a unified system of energy efficiency indicators at the national level, methods for their assessment and analysis. The energy intensity of GDP is almost the only universal instrument by which international and regional comparisons of energy efficiency levels of national economies are possible. It is shown that in recent years in Ukraine there has been a clear tendency to reduce the energy intensity of the national economy in almost all spheres. The State Agency on Energy Efficiency and Energy Saving of Ukraine has developed tables of primary data and a methodology for calculating energy efficiency indicators of the Ukrainian economy. Primary data and calculation indicators are formed by such sectors as industry, transport, housing, agriculture, services. The article shows that recent methods for evaluating energy efficiency based on modeling the efficiency limit, namely, DEA and SFA models, have become a popular tool for evaluating energy efficiency. Despite a number of its advantages, the DEA method does not take into account statistical noise. In contrast to DEA models, SFA models use the Shepard distance function to determine the energy efficiency index and take into account statistical noise.

The purpose of the article is to determine the economic and bioenergy efficiency of bioorganic fertilizer based on digestate, taking into account the cost of basic nutrient elements. The article presents calculations of economic indicators of the examined elements of the technology of growing corn for grain and vegetable crops in Ukraine, which indicate that the cultivation of these crops is economically beneficial in all versions. The study found that increasing the economic efficiency of corn production for grain and vegetable crops when applying different norms of fertilizer application is achieved due to the more significant positive impact of yield growth compared to additional costs associated with the use of these agritechnical means, while additional costs caused by the use of fertilizers pay off many times. It is proved that the use of mineral fertilizers and their combination with high norms of bioorganic fertilizer (digestate) for corn and vegetable crops contributes to an increase in yield, and the energy efficiency of this fertilizer is quite high, which indicates the energy saving concerning the studied technology of growing crops. It is advisable to apply such fertilizer norms at which it is possible to obtain the greatest energy output at optimal costs, ensuring compliance with the priority policy of energy saving in agricultural production. The theoretical and practical provisions on the ecological problem (utilization of livestock waste, in particular in the case of pig farms), the energy problem (biogas production in a biogas plant) and the agronomic problem (obtaining organic fertilizer) have been further developed, which ensures an increase in yield and improvement of the quality of agricultural and vegetable crops, that is, makes it possible to obtain high-quality crop and vegetable products during utilization of livestock waste. The proposed approach to the economic assessment of technologies for growing corn for grain and table root crops, depending on the fertilizer application system, makes it conceivable to increase the level of productivity of agricultural and vegetable crops, provided that bioorganic fertilizers are effectively used in modern conditions of a sharp increase in the cost of mineral fertilizers. At the same time, the energy efficiency of growing corn for grain and table root crops depending on the fertilizer system has been determined, which will increase crop yields in the absence of an increase in fertilizer costs.

Problem. At the present stage of science and technology development the problem of creating energy efficient vehicles is solved by electric vehicle designing: electromobiles and hybrid vehicles. Despite perspectives of a battery electric vehicles, it could be complied with a “Zero Emissions” criterions only in case if the electricity is generated from renewable sources. In addition, electric vehicle may not always provide the desired range on charge. Lithium-ion batteries are now used to power the electric drive, and an important problem of that is a significant weight which vehicle have to carry, it is also necessary to balance their elements, which significantly increases the charging time from the external mains. Goal. The goal of the work is to develop the theoretical basis for the creation of a system for the conversion of the "mild hybrid" vehicles in operation. Methodology. Many countries cannot afford to make the rapid transition to renewable electricity and replace the fleet with electric vehicles. Instead, a faster effect can be obtained if you re-equip vehicles that are already in use to hybrids. To successfully fulfill this goal, it is necessary to justify the parameters of the hybridization system of vehicles in order to obtain significant energy efficiency with a favorable payback period. Results. The analysis of hybrid classification and drive architecture allowed to offer new functions for "micro hybrid" and "mild hybrid" technologies. Analysis of power losses during the movement of the vehicle allowed to predict the number and power of electric motors sufficient to perform new functions. Originality. The structural scheme of the hybridization system of the motor vehicle which provides its conversion into a hybrid is developed. The study is aimed primarily at improving the "mild hybrid" technology in which electric motors of relatively low power, which are not inherent in this technology, are proposed to partially implement the functions inherent in the technology of "full hybrid". Practical value. The combination of the features of "micro hybrid" and "full hybrid" technologies in "mild hybrid" technology should provide sufficient energy efficiency, ease of installation of the system equipment and low costs.

The study is devoted to energy efficiency management of induction motors with a short-circuited rotor of low and medium power and is a continuation of the development of the theory of compensated asynchronous motors. The purpose of the study is to substantiate the influence of the capacitance value of the internal capacitive reactive power compensation of an asynchronous motor in starting mode. The performed mathematical modelling of the compensated asynchronous motor allowed investigating quasi-transient electromagnetic processes considering the spatial and temporal orientation of the currents of the main and additional windings of the stator and rotor phases of the compensated asynchronous motor. Achieving this goal is based on establishing the regularities of the influence of the value of the compensating capacitance on the energy characteristics of a compensated asynchronous motor during its start-up and reaching the nominal electromagnetic moment on the rotor shaft. Numerical modelling is performed at the 30o spatial shift angle of the phase axes of the main and additional phase windings of the stator of a compensated asynchronous motor. This ensures that the currents of the main and additional windings of the CAM stator are equal. As the numerical experiment showed, changing the value of the compensation capacitance gives an idea of the conditions for ensuring the normal excitation mode of such an electric device. Ensuring normal excitation during the start-up of a compensated asynchronous motor leads to changes in the energy parameters of the machine – minimising power losses in the windings and reactive power consumption by the motor and increasing its power factor. It is established that the value of the compensation capacitance required to ensure the normal excitation mode during start-up and the steadystate normal mode of a compensated asynchronous motor differ. As a result of modelling, it was found that in order to ensure an energy-efficient starting mode and acceleration to the nominal slip, the value of the compensating capacity of an asynchronous motor should be almost 5 times greater than for a steady-state nominal mode. The results of these studies can be useful for improving the energy efficiency of micro power grids that operate small-and medium-power asynchronous motors

Purpose. The aim of the work is to study various aspects of the implementation of the nZEB - concept of buildings in European countries and to identify the main problems and obstacles to the scaling and development of buildings with near zero energy consumption and the use of this experience for Ukraine. Methodology. Analysis of regulatory documents, scientific papers and practices on the use of the nZEB concept in European countries. Findings. A review of legal documents, scientific papers and practices on the implementation and consolidation of the definition of the concept of buildings with almost zero energy consumption in European countries as a complement of a highly energy efficient building and renewable energy sources, energy efficient materials and technologies was carried out. Options for a detailed assessment of the new construction of the nZEB residential sector were considered. The impact of possible climate change on the characteristics of nZEB during the life cycle, including heating and cooling needs, is analyzed. Examples of the implementation of the nZEB concept in the renovation of buildings for various purposes are given. The emphasis is on the possible inconsistency and harmonization of nZEB standards with the best financial solutions and the sequence of implementation of approaches to ensure near zero energy consumption by buildings for various purposes for different climatic regions of Europe, the main challenges and obstacles in increasing the share of use of such buildings are analyzed. Originality. Various aspects of the implementation of the nZEB concept are grouped and analyzed, from regulatory documents, government incentives, balance in the concept of energy efficient solutions and the share of renewable energy sources, to technical and cultural-behavioral barriers. Practical Value of the work lies in the use of the above approaches and the experience of European countries for scaling the houses of the nZEB concept in the conditions of Ukraine. [ABSTRACT FROM AUTHOR]

Purpose. The purpose of the study is an experimental analysis of the behavior and changes in thermophysical properties of the most widely used thermal insulation systems during their entire operational life. Method. In order to study the thermophysical properties of various options for the thermal insulation of wall-enclosing structures, measures were taken to modernize the administrative building and a complex for the study of heat losses was developed. A comparison of experimental data obtained during the operation of heat-insulating structures over a long period of operation is carried out. Results Experimental data on temperature fluctuations and the distribution of heat flow density of a thermomodernized section of a wall-enclosing structure insulated by various methods were obtained from February 16-17, 2013 and January 16-17, 2022, and a comparison of the values of the actual coefficients of thermal conductivity of various heat-insulating materials in the first approximation was carried out. Scientific novelty. The need to assess the influence of the service life on the thermal and physical properties of heat-insulating materials used in thermomodernization of buildings of various purposes is experimentally substantiated. Practical significance. An important factor that is not taken into account when designing heatinsulating shells is presented and constructed, and the way of its research is indicated. [ABSTRACT FROM AUTHOR]

The influence of the structure of the electromechanical water supply system of a multi - storey building on its energy efficiency is investigated. A quantitative estimate of the reduction in the efficiency of the system compared to the supply of water to the top floor, depending on the number of floors. A complex mathematical model of the system with one and two risers (asynchronous motor - pump - branched hydraulic network) with determination of parameters of operating modes taking into account the mutual influence of system components is developed. The value of the system efficiency criterion as the ratio of the potential energy of water at the consumer to the consumed energy is substantiated and quantified. The electromechanical water supply system of a multi-storey building with two levels of risers consumes 30% less energy than the system with a single riser, due to the reduction of the amount of excess pressure in consumers of lower floors. [ABSTRACT FROM AUTHOR]

The execution of any project type, especially engineering-based projects, is usually time-based, efficiency-driven, and cost-effective. These factors are the deterministic parameters that engineer successful project completion. The application of scheduling models remains the best technique for achieving these three factors to their best degrees. Therefore, this study was centered on the impact study of applying the scheduling model in harvesting methane gas from methane clathrates deposits. Various data on gas hydrate reserves in the Niger Delta region of Nigeria were collected from relevant literature, studied, and analyzed. Such data includes the pictorial representation and description of the gas hydrate site in the Niger Delta region of Africa and various shapes and sizes of gas hydrate perimeters in the studied region positions of the gas reserves. The normal faults are projected on a bathymetric map of the study area and the bathymetric map of the Pockmark (with the stippled black line indicating the sea floor projection of a prominent N-S trending fracture in 3-D seismic data). As a type of scheduling model, the critical path method (CPM) was applied to develop the project’s work sequence using the activity on node (AON) architectural technique and Primavera P6 software after carefully identifying the primary operations involved in the project and their respective sub-operations or work breakdown structure (WBS). The risks associated with each operation were meticulously identified, with their consequent impact and exposure matrix determined using probabilistic measures of 1-5 according to the degree of the risk. Mitigation strategies were recommended for all the identified risks. The cost benefits of the project were X-rayed using parameters such as net present value (NPV), project payback time, internal rate of return (IRR), and net cumulative cash flow. From the results obtained, the CPM schedule showed that the project execution would last approximately ten months. All the operations involved in the project execution plan were all critical, proving that each activity should be completed within the scheduled run period. Else, the entire project would be affected. Also, risks with a high exposure matrix of 25, 12, and 4 were mitigated to 5, 3, and 0 using the recommended strategies. In addition, the project yielded an NPV of $20,736,951.04for the run period of 22 years after the execution of the project, IRR of 14%, and a payback time of 8 years (adding 2023 – the year of project execution) provided the daily production rate is maintained within 60,000-65,000MSCF/day. If the daily production rate increases, the cash flow and payback time will decrease. Therefore, the application of CPM in extracting methane gas from gas hydrates positively affected the operation through the vivid insights provided in workflow pattern/methodology risks effects and cost benefits.

The most critical parameters of the microclimate in greenhouses are air and soil temperature, air and soil moisture, plant illumination, and carbon dioxide (CO2) concentration in photosynthesis. New energy sources and resource-efficient management of microclimate parameters in greenhouses can be utilized to reduce greenhouse crop cultivation costs and increase profits. As the plant mass increase depends on photosynthesis, which involves the formation of glucose in the plant chloroplasts from water and carbon dioxide under the influence of light radiation, the saturation of greenhouses with carbon dioxide has become popular in recent decades. However, insufficient light slows down the process of glucose formation, while excessive light intensity negatively affects photosynthesis. Based on the experimentally proven Van Henten model of plant growth and using the MATLAB environment, a methodology was proposed, and the dependence between CO2 concentration and leaf lettuce illumination power required for maximum photosynthesis was determined. It is equal to 0.57 ppm/(W/m2). Such dependence should be considered when designing control systems to reduce resource and energy costs for greenhouse crop cultivation while ensuring maximum yield.