Energy Efficiency Coefficient Research Articles

Regional differences and catch-up analysis of energy efficiency in China’s manufacturing industry under environmental constraints

For coordinated regional growth and the development of high-quality manufacturing, China must narrow its regional energy efficiency gap and catch up inter-regionally. This paper focuses on whether China’s inter-provincial manufacturing energy efficiency has technological diffusion and a catch-up effect and explores its possible influencing factors, which are important for narrowing the differences in China’s manufacturing energy efficiency and promoting the improvement of the overall level of efficiency. Between 2011 and 2020, 30 Chinese manufacturing industries will be evaluated using a non-radial distance function model under environmental conditions. By employing the Dagum Gini coefficient method, regional disparities were analyzed, with hyper-variable density and efficiency discrepancies between regions making a noteworthy contribution. This paper evaluated a catch-up effect by constructing a frontier productivity model that considered the influence of China’s manufacturing energy efficiency. Results show a general rise in energy efficiency, particularly in coastal regions, higher than inland ones. The Gini coefficient of energy efficiency in manufacturing experienced a slight increase; however, when comparing it to the regional efficiency frontier, the catch-up effect and technology diffusion effect of China’s provincial manufacturing energy efficiency become more pronounced when taking into account the national efficiency frontier; the sub-regional manufacturing energy efficiency catch-up effect has different performances; the catch-up and technology diffusion effect is more evident after controlling for Economic development, innovation levels, the environmental regulation, and the proportion of high-energy-consumption output value and other influencing factors.

Increasing energy efficiency and flow coefficient by determining fluid behaviours with computer aided design and CFD analysis in isolation valves

In this study, it was aimed to convey theoretical and practical development of the double eccentric butterfly valve, which would be the first in the sector, with highly efficient, saves energy, has a long life, and requires less maintenance. For this purpose, a prototype with lower weight and higher flow coefficient has been developed by the Computational Fluid Dynamics (CFD) method. Thanks to the use of computer aided design and simulation techniques, environmentally friendly and highly efficient valves have been produced, improving competitive conditions and an innovative product has been obtained in the sector. The design, CFD analysis, and casting simulation were carried out by Solidworks, ANSYS, and Anycasting computer programmes respectively. At the same time, as a result of this study, a design suitable for an innovative production technique that leads to less energy and less waste has been obtained. Innovative material selection and casting techniques were used by optimising the total material weight and valve cost.

Heat transfer performance analysis of medium - deep coaxial borehole heat exchanger (CBHE): combination of heat extraction operation test and numerical simulation

Abstract Geothermal energy is a clean and renewable energy source that can effectively reduce carbon emissions. Coaxial borehole heat exchanger (CBHE) is a crucial component of the geothermal mining system. To understand the heat transfer mechanism of a CBHE and to design its construction, this paper analyzes the geotechnical thermal response characteristics of CBHE under constant power conditions. COMSOL was used to simulate the performance of the heat exchanger during intermittent operation in both summer and winter. The results indicate that the inlet water temperature and the thermal conductivity of the grouting material have a weak impact on the energy efficiency coefficient of the heat exchanger. The energy efficiency coefficient can increase by about 22% when the inner pipe's thermal conductivity is lower. The temperature difference between the medium flowing into the inner pipe at the bottom of a shallow cased buried pipe and the medium flowing out of the inner pipe defines the thermal short circuit value. The influence on the thermal short circuit value is on the order of the inner pipe thermal conductivity, grouting material thermal conductivity, and the inlet water temperature. The fluctuation of soil temperature in the summer is greater than that in the winter, the soil temperature of shallow-buried pipes is easier to recover in the winter. The characteristic law obtained in this paper provides a valuable reference for the scientific design of CBHE.

Stiffness optimization design of wheeled-legged rover integrating active and passive compliance capabilities

Compliance capability is one of the most important properties of suspension systems for rough-terrain robots. This imposes specific requirements on system stiffness design, which directly determines the platform's performance in response to external stimuli. To address the challenge of stiffness optimization design in active and passive compliant systems, this paper proposes a novel and practical method for optimizing stiffness for a terrain-adaptive wheel-legged rover. Firstly, the kinematic model of this multi-degree-of-freedom platform is established. Secondly, the deformation capability coefficient, load capacity coefficient, energy efficiency coefficient, and dynamic stability coefficient are derived as performance indices to assess the behavior of the system. By establishing the relationship between joint configuration variation and system stiffness, stiffness parameters could be evaluated through these performance indices. Ultimately, the global optimum stiffness parameters are selected from the refined intersection of the individual performance optimal domains. Thirdly, the optimum parameters are calculated and applicability verified numerically. The designed parameters are verified experimentally on a wheeled-legged rover. The experimental results demonstrate that the proposed algorithm can find the parameter combination that achieves optimal system performance, thereby enhancing the system's terrain adaptability.

Analysis of refrigerants used in supermarket commercial equipment and the potential for increasing energy efficiency and reducing environmental impact

Refrigerants used in the commercial equipment of supermarkets are the object of the research. The Montreal Protocol calls for a complete phase-out of hydrochlorofluorocarbons (HCFCs) by 2030, and the Kigali Amendment regulates the use of hydrofluorocarbons (HFCs) from 2019. Developed countries began phasing out HFC use in 2019, while developing countries plan to freeze HFC consumption from 2024. These global efforts are aimed at reducing the depletion of the ozone layer and combating climate change. The number of supermarkets in the world varies greatly: in Europe they number from 110 thousand to 115 thousand, and in China – from 65 thousand to 70 thousand, which reflects various needs in refrigeration equipment. Stringent environmental regulations are forcing the commercial refrigeration sector to remain globally competitive. Modernization of supermarkets using natural refrigerants is important for solving emerging challenges. The results of the study show significant improvements in energy efficiency ratio (EER) and coefficient of performance (COP) when using a mixture of hydrocarbons (R290: 85 %, R600a: 15 %) compared to traditional refrigerants R404a, R449a and R502. Specifically, at the evaporation temperature of Tevap=–10 °C, EER increased by 38–44 % and COP by 26–31 % compared to R404a and R449a, respectively. At Tevap=–25 °C, EER increased by 17–34 % and COP by 2–22 % compared to R404a and R449a. Additionally, compared to R502, the hydrocarbon blend showed a 38–44 % increase in EER and 28–31 % COP at Tevap=–10 °C, and a 17–34 % increase in EER and 5–22 % COP at Tevap=–25 °C. These results highlight the advantages of the hydrocarbon mixture at different evaporation temperatures, indicating its potential to improve energy efficiency in refrigeration applications. The obtained data suggest the possibility of a wider application of the mixture of hydrocarbons in commercial refrigeration plants, offering both improved performance and compliance with safety regulations.

Economic and energy efficiency of resource-saving technology for switchgrass cultivation

Purpose. The study aimed to compare the efficiency of the resource-saving technology with the conventional technology for switchgrass cultivation using the developed methodology for assessing the economic and energy efficiency. Methodology / approach. The study used general and special methods, including the methodology of scientific research in agronomy, laboratory determination of dry matter content in biomass, quantitative-weight analysis to establish crop yield, and the authors’ improved methodology for assessing economic and energy efficiency. The research results were statistically processed using variance and comparative analysis. Results. The results of the research on the use of resource-saving cultivation technology in comparison with conventional technology show an increase in switchgrass biomass yield from 14.6 to 15.7 t/ha, an increase in economic efficiency with profitability growth from 73.8 to 79.0 %, and an increase in energy efficiency with a growth of the energy efficiency coefficient by 0.7 – from 4 to 4.7 (average level of energy efficiency) when applying a specific complex of agrotechnical measures. When using resource-saving technology, the average full cost of cultivating switchgrass for six years is 8305.6 UAH/ha, compared to 7952.8 UAH/ha with conventional technology. However, resource-saving technology generates an average sales revenue of 14867.5 UAH/t, which is 1045 UAH/t more than conventional technology (13822.5 UAH/t). Originality / scientific novelty. For the first time, a field experiment was conducted to compare switchgrass cultivation using resource-saving and conventional technologies. The authors have developed a methodology to assess the economic and energy efficiency of cultivating switchgrass. The results indicate that the efficiency of switchgrass biomass production is influenced by improved cultivation technology. The authors have developed a three-dimensional econometric model that demonstrates how the profitability level depends on the chosen switchgrass cultivation technology. Practical value / implications. The research results have practical significance as they have led to the development of a methodology and evaluate the economic and energy efficiency of switchgrass cultivation. These results will be useful for agrarian enterprises to save resources.

SPECIFIC ENERGY CAPACITY OF PROCESSING AND ENERGY EFFICIENCY FOR PROCESS OF GRINDING WITH WHEELS FROM SUPERHARD MATERIALS

The analysis of modern research shows that when evaluating the specific energy intensity of the abrasive processing process, one should pay attention not only to the indicators of grinding power and material removal rate, but also to the indicator of the wear of the abrasive tool, which we will show below for the grinding tool made of superhard materials. It is shown that the traditional method of estimating the specific energy capacity based on the ratio of the grinding power to the processing productivity does not provide an adequate solution, since with it the specific heat capacity of processing exceeds the specific heat capacity of melting of the processing material by almost an order of magnitude. Therefore, it is the application of a new approach to the assessment of the specific energy intensity of diamond grinding, taking into account the wear of the working layer of the diamond wheel, and makes it possible to estimate the indicators of the specific energy intensity of grinding and the energy efficiency coefficient. It has been proven that when estimating the specific energy capacity of grinding metal-ceramic composite materials consisting of a low-melting and refractory component, the latent heat capacity of melting of the low-melting component should be taken as the basis. It is shown that the plastic mode of grinding occurs precisely when the specific energy capacity of grinding, taking into account the wear of the wheel, becomes close to the specific heat capacity of melting of a brittle material.

Development of Technology and a Convertеr for Neutralizing Greenhouse Gases Emitted from Automobiles

The article touches upon the issues of global warming associated with carbon dioxide (CO2) emissions into the atmosphere from vehicle internal combustion engines (ICE). To neutralize existing greenhouse gases emitted by ICE, in particular CO2, the interaction of the latter with various chemicals has been studied. The dynamics of exhaust gas emissions from ICE cylinders were observed. The experimental research was conducted to develop a greenhouse gas neutralization technology. Carbon dioxide neutralization converter with three neutralization batteries and a homogenization device is presented. This converter can guarantee CO2 neutralization of up to 92%. The formation of CO2 in the cylinders of modern petrol engines is due to the final combustion of the air-petrol fuel mixture. The combustion of the latter in the cylinder can be heterogeneous and diffusive. In addition, CO2 is generated in large quantities during diffusion combustion. The most effective method of diffusive combustion was chosen by the constructors of modern ICE, which is the formation of an artificial turbulent gas-dynamic condition for the fuel mixture due to the increase in the temperature of the air adsorbed in the cylinder, which ensures the engine's thermal energy efficiency coefficient of up to 35%. The CO2 volume in the exhaust gases of such engines reaches up to 16%. Thus, considering the perfection of modern ICE design for providing a high-efficiency reaction for the hydrocarbon oxidation in the fuel mixture in the combustion chamber, it becomes apparent that the presence of about 16% CO2 in the fractional composition of emitted dissolved gases is a serious problem in terms of increasing the volume of greenhouse gases in the atmosphere. Therefore, the goal of this article is to develop a reduction technology.

Productivity and nutritional value of perennial cereal grasses in the Middle Cis-Urals

The purpose of the research was the assessment of feed productivity and nutritional value of 13 new varieties of meadow timothy, meadow fescue and awnless brome when cultivated for green mass in the Middle Cis-Urals. The research was carried out in 2018–2022 on sod-podzolic medium loamy soil of the Udmurt Republic. Meteorological conditions of the growing seasons during the years of the research were different: 2018, 2021 and 2022 were arid (hydrothermal coefficient – 0.89, 0.78 and 0.91, respectively), 2020 – slightly arid (HTC – 1.04), 2019 – waterlogged (HTC – 1.73). The beginning of regrowth of the studied varieties of perennial cereal grasses was noted in the third ten days of April; the grass reached mowing ripeness in 44–60 days. The yield of meadow timothy varieties on average for three years of using the grass stand was at the level of 3.5–3.9 t/ha of dry weight, meadow fescue – 2.3–2.4 t/ha, awnless brome – 4.5–4.7 t/ha. The “year conditions” factor had a primary influence on the variation in yield, density and height of the grass stand – 92.4…97.4 %, 62.9…79.2, 80.3…82.6 %, respectively. The “genotype x year” factor also influenced the number of shoots and their height. Fescue varieties were distinguished by a relatively high content of crude fat (2.5–3.1 %), sugars (15.6–17.7 %), and calcium (0.31–0.36 %). High content of crude fat (2.3–2.6 %), phosphorus (0.68–0.71 %), potassium (2.45–2.52 %), calcium (0.31–0.39 %) noted in plant samples of awnless brome varieties. A positive strong correlation between the yield of dry mass of cereal grasses and the content of phosphorus (r = 0.87…0.96) and potassium (r = 0.69…0.85) in it was revealed. Some varieties of perennial cereal grasses were distinguished by their nutritional value: meadow timothy varieties Sleipnir (Finland), Aturo (Germany) and Tamiza (Germany) with a yield per 1 hectare of metabolic energy of 32.3–34.4 GJ, digestible protein – 0.14–0.16 tons, feed units – 2.41–2.60 thousand; meadow fescue variety Karpatchi (Netherlands) – 21.2 GJ, 0.09 tons, 1.57 thousand; awnless brome variety Gvardeets (Russia) – 35.7 GJ, 0.25 tons and 2.58 thousand, respectively. Cultivation of Karpatchi fescue, Sleipnir timothy and Gvardeets brome is energetically and economically profitable: energy efficiency coefficient – 1.9; 3.0 and 3.6, profitability level – 65; 101 and 161 %, respectively.

Productivity of crop rotations with different types of fallow and their effect on the humus content in sod-podzolic soil the Middle Urals

The research was carried out in the conditions of the Perm Region on sod-podzolic heavy loamy soils in a long stationary plot trial, laid down in 1977. The purpose of the research is to study the effect of various types of fallow on crop rotation productivity and humus content in the soil. The data are given for two rotations (2009–2022) of fallow-grain–grass crop rotations with various types of fallow – with manurial, sown with clover, sown with melilot, sideral with clover and sideral with melilot – without mineral fertilizers and with fertilizers (N60P30K60). It was found that in the sown fallows, the mass of root and mowing plant residues of meadow clover and yellow melilot, depending on the nutrition background, reaches 4.08–4.36 t/ha with a nitrogen content of 41.8–46.9 kg/ha, phosphorus 16.7–18.6 kg/ha and potassium 42.7–69.6 kg/ha. In sideral fallow with clover and clover biomass, 6.99–9.04 t/ha and 6.83–8.53 t/ha of dry matter with a content of 133.5–148.1 kg/ha of nitrogen, 34.3–41.2 phosphorus and 121.2–148.9 potassium were supplied to the soil, respectively. The application of organic fertilizers in the fallow field contributed to an increase in the humus content by 0.19 abs.% to the initial (2.04 %) in the variant without mineral fertilizers and by 0.69 abs.% in the variant with the introduction of mineral fertilizers to the initial (2.08 %) Clover sideral fallow also contributed to an increase in the humus content in the soil by – 0.38–0.52 abs.%. There was an increased productivity of crop rotation with sideral melilot fallow (2.22–2.25 t/ha of grain units per year) relative to the traditional crop rotation with pure fallow (2.08–2.11 t/ha of grain units per year). Cultivation of crops in all studied crop rotations was energetically efficient, the energy efficiency coefficient was 3.63...4.48 in the variants without mineral fertilizers, against the background of NRK – 2.38...3.21.

Оценка эффективности смесей фестулолиума с люцерной в лесостепи Приобья (Западная Сибирь)

The results of the research of festulolium and alfalfa in a joint herbage with different methods of sowing and doses of mineral nitrogen conducted in the forest-steppe of Western Siberia in the period from 2020–2023 are presented. The growth and development of crops in the initial period of life, winter hardiness, productivity and economic feasibility of cultivation were taken into account both in favorable 2019–2021 (HTC = 1.0...1.29) and in unfavorable 2022–2023 (HTC = 0.6...0.99). A high response of perennial grasses was achieved in sowing festulolium one row + alfalfa three rows — 38.13 t/ha of green mass, which corresponds to a single-species alfalfa crop. Sowing with a mixture of seeds is 21% less productive. A positive effect was obtained from optimizing the level of cenosis and foliage of alfalfa by 56%, which was confirmed by an average correlation (r = 0.58). The energy efficiency coefficient (CEE) had maximum values of 9.8–11.7 and was characterized as high, the profitability of cultivating mixtures was 407–465%. A positive effect was obtained when N30 was introduced into the sowing of festulolium one row + alfalfa three rows — 21–36% to 37.41 t/ha of green mass. In comparison with the unfavorable background, the share of festulolium in the yield of mixtures increased to 58–71%, alfalfa decreased to 29–42%. CEE = 4.9–5.6 (the value is from medium to high), the profitability of cultivating mixtures is 325–378%. The application of mineral nitrogen N60 to joint crops of festulolium and alfalfa increases the collection of green mass compared with single-species sowing of festulolium by 10–20%, to 34.74–37.93 t/ha of green mass due to the maximum proportion of cereals in mixtures — 62–80% with its responsiveness to fertilization. CEE = 4.5–4.9 (average value), the profitability of cultivating mixtures is 323–365%.

Complex Use of the Main Marine Diesel Engine High- and Low-Temperature Waste Heat in the Organic Rankine Cycle

The decarbonization problem of maritime transport and new restrictions on CO2 emissions (MARPOL Annex VI Chapter 4, COM (2021)562) have prompted the development and practical implementation of new decarbonization solutions. One of them, along with the use of renewable fuels, is the waste heat recovery of secondary heat sources from a ship’s main engine, whose energy potential reaches 45–55%. The organic Rankine cycle (ORC), which uses low-boiling organic working fluids, is considered one of the most promising and energy-efficient solutions for ship conditions. However, there remains uncertainty when choosing a rational cycle configuration, taking into account the energy consumption efficiency indicators of various low-temperature (cylinder cooling jacket and scavenging air cooling) and high-temperature (exhaust gas) secondary heat source combinations while the engine operates within the operational load range. It is also rational, especially at the initial stage, to evaluate possible constraints of ship technological systems for ORC implementation on the ship. The numerical investigation of these practical aspects of ORC applicability was conducted with widely used marine medium-speed diesel engines, such as the Wartsila 12V46F. Comprehensive waste heat recovery of all secondary heat sources in ORC provides a potential increase in the energy efficiency of the main engine by 13.5% to 21% in the engine load range of 100% to 25% of nominal power, while individual heat sources only achieve 3% to 8%. The average increase in energy efficiency over the operating cycle according to test cycles for the type approval engines ranges from 8% to 15% compared to 3% to 6.5%. From a practical implementation perspective, the most attractive potential for energy recovery is from the scavenging air cooling system, which, both separately (5% compared to 6.5% during the engine’s operating cycle) and in conjunction with other WHR sources, approaches the highest level of exhaust gas potential. The choice of a rational ORC structure for WHR composition allowed for achieving a waste heat recovery system energy efficiency coefficient of 15%. Based on the studied experimental and analytical relationships between the ORC (generated mechanical energy) energy performance (Pturb) and the technological constraints of shipboard systems (Gw), ranges for the use of secondary heat sources in diesel operational characteristic modes have been identified according to technological limits.

Numerical investigation on the heat storage/heat release performance enhancement of phase change cemented paste backfill body with using casing-type heat pipe heat exchangers

Cemented paste backfill mining technology that recycling tailings and waste rocks can effectively reduce heat damage. Heat pipe exchangers, demonstrating much higher thermal conductivity than water pipe exchangers, led to the development of a novel phase change backfill body system with a built-in casing heat pipe exchanger (HP-PCB). Numerical analysis revealed that, for the melt and solidification of a large amount of PCM, the temperature step phenomenon was observed at both heat storage and heat storage/heat release coexistence stages. Increased surrounding rock temperatures enhanced heat storage and heat release capacities, but reduced system energy efficiency. The optimal water flow velocity was identified at the laminar-turbulent transition flow rate, 0.32 m/s. An increase in water inlet temperature resulted in lower heat release capacity and system energy efficiency. The energy efficiency of the HP-PCB system exceeded that of the traditional water pipe-backfill system by 37.22%. At a surrounding rock temperature of 45 °C, cooling water velocity of 0.32 m/s, and a 6 °C inlet water temperature, the HP-PCB system achieved its highest energy efficiency coefficient, 86.38%. These findings highlight the HP-PCB system potential for efficient geothermal energy extraction in mine.

EN Improving the energy efficiency of refrigeration equipment with a direct sales function

The increased use of refrigerants with low global warming potential GWP over the past decade indicates that manufacturers are already making gradual replacements with refrigerants with reduced environmental impact. Thus, in addition to HFC gas phase-out requirements, most EU countries are pursuing a trend to reduce the energy consumption of refrigeration appliances. Such countries restrict the import of equipment that does not meet the energy efficiency requirements. This paper presents the ecodesign of refrigeration equipment in relation to the requirements of the sales market using the Regulation on Conformity Assessment Procedure. HVAC&R equipment contributes to GHG emissions in two ways: directly through refrigerant leakage or venting, and indirectly through electricity use, the latter accounting for up to two-thirds of GHG emissions. The paper compares the energy and environmental characteristics of refrigerants R404a and R290 in freezer M200V. The experimental results show that the highest COP va­lues in the system for R404a and R290 are 3.02 and 3.19, respectively. Possibilities of complete transition from F-gases to natural analogues with GWP ≈ 0 are shown. At application of R290 its advantages on energy efficiency are obvious - reduction of electric power consumption of freezing chests on 8,9 %, influence on environment R404A – GWP=3260, R290 – GWP=3. The calculation of energy efficiency class for freezing chest was made. To improve energy efficiency, a number of design modifications were made: the density of the thermal insulation material and the compressor were changed. The energy consumption of the modified version at the second climatic class was measured at 1.23 kW/24h, and the energy efficiency coefficient according to the calculation EEI =34.904, which corresponds to the energy efficiency class «C».

Properties of dark gray forest soil in the cultivation of cereals according to various basic processing systems

The purpose of the research is to establish the influence of various systems of basic dark gray forest soil processing with prolonged use on the transformation of the most important fertility elements. The results of prolonged (1988-2022) exposure to processing systems in the grain-steam crop rotation are presented: dead fallow, winter rye, spring wheat, spring barley, in the northern forest-steppe of the Tyumen region of the Russian Federation. The basic tillage systems were compared: dump, non-dump, combined, differentiated, flat-cut, surface. The peculiarities of the transformation of fertility elements under prolonged exposure to basic processing systems of varying intensification degrees are determined. It was found that the long-term use of basic treatment systems of varying minimization degrees in conditions of complex chemicalization ensured the formation of water-physical properties, nutritional conditions and phytosanitary conditions in their values slightly inferior or close to the control version of the dump processing system. Tillage systems with minimization elements reduced the energy efficiency coefficient in comparison with the dump system against the background of fertilizer application by 4.5‑11.5%, against the background without fertilizers – by 7.7‑18.4%. The lowest decrease in efficiency in comparison with the dump processing system for both nutrient backgrounds was for the combined processing system – 4.5‑7.7 %.

ECONOMIC AND ENERGY EFFICIENCY OF PEA INOCULATION WHEN GROWING CROP IN THE SYSTEM OF ORGANIC PRODUCTION

Objective. To analyse economic and energy efficiency of inoculants based on a new strain Rhizobium leguminosarum Г222 in the technology of growing field peas. Methods. The calculation of the indicators of the economic efficiency of the cultivation of field peas for various seed treatment variants was carried out using methods and commonly used methodological approaches, which are based on a comparison of the results of the application of a certain agricultural measure with the costs of its implementation. The following indicators were studied: profit, cost per unit, payback of additional costs, as well as the level of profitability of production. Modelling of technological costs in the conditions of production scales using typical pea growing technologies has been used. The main agrotechnical operations have been modelled according to resource cost standards and product costing algorithms with the inclusion of additional operations and costs associated with the use of studied inoculants. In order to calculate the main indicators of the energy efficiency of the applied means for treatment of the pea seeds, the costs of all types of used resources and the obtained products were converted into energy equivalents according to generally accepted methods. Results. The use of inoculants based on R. leguminosarum Г222 contributes to increase in all the main indicators of economic efficiency: cost per unit, profit based on 1 ha of sown area and the level of profitability increase with the corresponding level of payback of additional costs. This is due to the higher rates of yield growth (and, accordingly, cash receipts) in experimental variants compared to the rates of increase of costs per unit area associated with the use of inoculants. According to the results of the energy efficiency analysis, it has been shown that the inoculation of peas with a new strain provides a high level of energy efficiency in terms of the ratio of the energy content of the obtained products to the energy consumption for its production (energy efficiency coefficient). The results of the comparative analysis of the calculated indicators show that in the variants with bacterization, there is a significant lag in the rates of increase of anthropogenic energy consumption per 1 ha of sown area versus the increase in yield and energy content of the obtained products. Additional energy costs associated with the use of inoculants are 8.00–24.39 times paid back by the energy of the additional harvest. Conclusion. The results of the analysis suggest high economic and energy efficiency of the use of the new strain R. leguminosarum Г222. The variant in which the use of R. leguminosarum Г222 was combined with a polysaccharide-protein complex is the most efficient.

Development and enhancement in drying performance of a novel portable greenhouse solar dryer

The increasing demand for drying technology for agriculture and food products has gained significant attention due to population explosion and inadequate resources available. The present study focuses on the concept of enhancing the drying performance of portable greenhouse solar dryer. The experimental investigations for evaluating the dryer performance were carried out while drying out onion slices. The experimentation was carried out in 4 different modes to demonstrate the effect of various modifications implemented to improve the dryer performance. The active greenhouse solar dryer (AGHSD) is the first working mode which comprises of the conventional drying system with active mode of removing moisture. The second working mode uses recirculating fans along with exhaust fans (AGHSD@circulating fans). In the third working mode an Evacuated Tube-type solar Air Heater was added to along with previous modification (AGHSD@circulating fans + ETAH). The last working mode adds an air flow distribution system to the incoming pre heated air from the Evacuated Tube-type solar Air Heater (AGHSD@circulating fans + ETAH + air flow system). Various performance characteristics like moisture ratio, heat utilization factor, coefficient of energy, heat gain and thermal efficiency of the dryer are used to analyze the changes in the drying performance. AGHSD@circulating fans + ETAH + air flow system reduced the moisture ratio in the onion slices to 5.32% from 95% in one day, compared to 19.99% for AGHSD and 46% for open sun drying. The heat utilization factor and coefficient of energy for AGHSD@circulating fans + ETAH + air flow system and AGHSD@circulating fans + ETAH improve by 10% and 15% respectively as compared to AGHSD. AGHSD@circulating fans + ETAH + air flow system shows improved heat gain of 29.53% and shows the best drying rate for the developed drying system. The thermal efficiency of AGHSD@circulating fans + ETAH + air flow system is around 60% while for AGHSD is around 41% which is higher than the thermal efficiency of 20% for sundried samples.

Efficiency of sugar beet cultivation in the Steppe of Ukraine

Purpose. To determine the features of the economic and energy efficiency of growing sugar beet in the Steppe of Ukraine. Methods. Field research was conducted during 2020–2022 in the Chkalov Agrocompany LLC (Kirovohrad region). The scheme of the experiment provided for the cultivation of sugar beet against the background of the use of a water-retaining agent (without hydrogel; hydrogel Aquasorb, 300 kg/ha), under application of different fertilizers (without fertilizers – control; manure, 20 t/ha; N170P180K350; Leonardyt, 400 kg/ha; Parostok 20, 400 kg/ha) and foliar application of fertilizers during the growing season (without foliar feeding; Humifild SE, 2 kg/ha in the BBCH stage 30 and 39). Organic and mineral fertilizers (PK) were applied in autumn at ploughing and nitrogen was applied at cultivation in early spring. The water-retainer was applied to the soil two weeks before sowing the crop in the zone of the row, based on the data of the GPS tracker. The rest of the agricultural activities corresponded to the generally accepted crop cultivation technology in the area of research. The calculation of economic indicators was performed using prices of 2023. Results. In terms of income from the sale of sugar beet roots, the best treatment was the use of Aquasorb hydrogel, fertilization of sugar beet with Leonardyt and foliar application of fertilizer Humifild, where 106.8 thousand UAH/ha was obtained. In terms of costs for crop cultivation technology, the most expensive treatment was the application of mineral fertilizers (75.9–84.4 thousand UAH/ha). In contrast, application of new organic fertilizers provided better results in terms of the costs of growing sugar beet. In particular, in the treatments where hydrogel was not applied, the costs of fertilization with Leonardyt were 37.3–39.8 thousand UAH/ha, while with the use of Aquasorb, the treatment with Leonardyt had a cost of 43.3–45.8 thousand UAH /ha. On the other hand, the costs of using organic fertilizer Parostok were 39.6–42.1 and 45.6–48.1 thousand UAH/ha. In the treatment with Parostok followed by foliar application of Humifild, a profit of UAH 60.6 thousand/ha was obtained. In case of application of Aquasorb hydrogel and fertilization with Leonardyt fertilizer followed by foliar feeding with Humifild, a profit of UAH 61,00 per 1 ha was obtained, which was the maximum in the experiment. Profitability of 145.0% was obtained with the application of Parostok 20 fertilizer and 143.8% with Humifild applied against the background of Parostok. In the treatment with Leonardyt, the profitability was 142.6%. With the use of Aquasorb hydrogel and Leonardyt fertilizer, the level of profitability was somewhat lower and proportional to the increase in technology costs (133.2%). Conclusions. In the case of applying Aquasorb hydrogel (300 kg/ha) to the row zone before sowing and fertilizing sugar beet with Leonardyt or Parostok 20, more than 300 GJ/ha of energy yield was obtained. The maximum accumulation of energy in the harvest (312.5 GJ/ha) was obtained in the treatment where moisture retainer, Parostok 20, and Humifild were applied. When Parostok 20 was used as the main fertilizer, the coefficient of energy efficiency was 4.70, while with foliar application of Humifild it was 4.72. In the treatments where moisture retainer and Parostok 20 were applied, with or without subsequent foliar application of Humifild, the coefficient of energy efficiency was 4.60 and 4.63, respectively.

Анализ урожайности сортов горчицы сарептской в условиях приазовской зоны Ростовской области

The article presents the results of research on the study of morphological and production indicators of mustard Sarepta in the conditions of the Azov zone of the Rostov region. It was found that among the studied varieties of mustard Sarepta, the best indicators were in the varieties Lux and Lera, forming a seed yield of 11.0 and 10.56 c / ha, respectively. The coefficient of energy efficiency of growing these varieties was 1.56 and 1.53. The increase in energy in the yield of dry matter was in the range of 10.56–11.04 MJ/ha, which is more than that of the standard Donskaya 8 variety by 1.64 and 1.02 GJ/ha, respectively. Keywords: SAREPTA MUSTARD, VEGETATION PHASES, BIOLOGICAL YIELD, ENERGY EFFICIENCY, ENERGY GAIN

Efficiency Modeling using the Mirror Surface of Heliostats in a Solar Power Tower

Analyzing the geographical location and climatic conditions of Turkmenistan, we conclude that solar energy is a priority among all renewable sources since the duration of sunny days in the country is from 270 to 320 days a year. Development, creation of large-scale solar power plants and use in remote desert regions of Turkmenistan is an urgent problem. The article considers the possibilities of creating a solar power plant based on a tower-type layout. The modes of the optical system in the natural and climatic conditions of Turkmenistan are calculated using a mathematical model, the coefficient of efficiency of using the mirror surface of the installation and the distribution of the level of instantaneous local values are determined. Figure 1 shows the movement of the Sun in the sky, which varies depending on the time of year. The results of the study show that the maximum increase in the energy efficiency coefficient can be achieved with the location of solar panels perpendicular to solar radiation with the dense placement of heliostats on the north side of the tower, then energy efficiency will increase by 25-40% in summer and 10-15% in winter.