In the recent years substantial growth of the demand for electricity took place in Myanmar; energy generation by existing sources (mainly hydropower) is not enough to provide constantly increasing consumption. The problem is most obvious in rural areas (more than 61 percent of the population) where grid extension is not justified economically whereas the cost of electricity produced by autonomous diesel generators is extremely high.

(Research purpose) The purpose of this research is the evaluation of economic and technical feasibility of small off-grid (standalone) photovoltaic (PV only) and hybrid photovoltaic-diesel (PV-diesel) power generation systems providing rural household electricity consumption in Myanmar.

(Materials and methods) Computer simulation using Homer pro simulation software was used. Three different load scenarios were envisaged – low, medium and high (1; 6 and 16 kilowatt-hour per day). Simulation was done for Tha Ngar village tract  with a population of about 3,000 people, which is typical in Myanmar.

(Results and discussion) The results of the simulation reveal that the levelized cost of energy (LCOE) for optimal hybrid (PV-diesel) systems lies in the range 0.37-0.51 US$, for PV only systems –  0.46-0.49 US$. It proves their economic feasibility compared to conventional diesel generator systems with LCOE 0.56-1.56 US$ boosted by high fuel prices in remote areas (2-3 times higher than urban price). For the high load scenario hybrid systems are more preferable, for low load (night time lighting only) PV only systems may be more effective.

Conclusions) It can be concluded that implementing solar energy is not only environmentally friendlier but also economically justified approach for providing household electricity demands of rural settlements in Myanmar without constructing expensive grid extensions.

The paper contains the analysis results of the influence of geometric and setup parameters of the plow working tools on agrotechnical indicators and traction resistance of a plow.

(Research purpose) To determine the agrotechnical indicators of tillage quality depending on the type of a plow moldboard and determine the optimal moldboard for loamy soils.

(Materials and methods) Agrotechnical indicators included crumbling, soil layer turnover, and the incorporation (embedding) degree of plant residues. More intensive lumpiness is observed as the content of clay particles increases. The angle of plow body setup relative to the furrow walls is changed using the middle bolts securing the plow body rack of the frame and installing additional washers on one of the two remaining bolted joints. For experiments on the influence of the inclination angle of the plow-bottom surface relative to the furrow wall, the plow bodies were located at angles of 30 to 55 degrees.

(Results and discussion) It has been established that at angles of 30-35 degrees, the diameter of clods increases to values exceeding the permissible norm by 10-20 percent. An increase in the angle of more than 45 degrees reduced the diameter of clods to 10-30 millimeters. With an increase in angle to 50-55 degrees, shearing chips changed into shifting chips. The authors determined traction resistance of plows with various types of moldboards and identified the results of analytical calculations and experimental data in field trials using a dynamometer. Traction resistance of the plow decreases as cylinder moldboards are substituted with screw (auger-type) ones.

(Conclusions) It has been determined that as the angle of plow body setup relative to the furrow walls increases, the size of soil fragments decrease, and shearing chips change into shifting chips. It has been proved that general-purpose and half-screw moldboards demonstrate the best agrotechnical indicators on loamy soils

The article presents the influence of used tillage machines and technologies of agricultural crops cultivation on mechanical soil erosion on slope agricultural landscapes. Under the action of tillage and sowing machines working bodies, the soil is systematically shifted down the slope.

(Research purpose) Identify ways to reduce mechanical soil erosion on the slopes in the cultivation of grain and row crops by improving technology and technical means.

(Materials and methods) The authors established that the mechanical soil erosion that occurred when processing slopes working bodies in the form of a triangular wedge depended on the parameters of the working body, the steepness of the slope and the movement direction of the unit relative to the horizontal field. Mechanical soil erosion in one field per season varied depending on the technology of cultivation, as it depended on the number and depth of treatments.

(Results and discussion) The authors showed that the transition from traditional technologies of cultivating grain and row crops to conservation, energy-saving and Strip-till technologies led to a corresponding reduction in erosion, and the transition to zero technology eliminated the occurrence of mechanical erosion. It was determined that during the cultivation of crops on slopes of 6 degrees there was no mechanical erosion per season by zero technology, by energy-saving technology did not exceed 15 millimeters, by soil protection technology – 35 millimeters, and by traditional – reached 145 millimeters. The authors noted that when cultivating corn by traditional technology on 6-degree slopes, mechanical soil erosion reached 87 millimeters per season. Therefore, to preserve the soil during the corn cultivation, they considered the transition to Strip-till technology.

(Conclusions) To reduce the mechanical soil erosion, the authors proposed to switch from traditional technologies for cultivating crops to soil-protective, energy-saving, zero technologies and Strip-till technologies.

To remove medium and large stones from mountain meadows and pastures with an exposure slope of up to 12 degrees, a new method and prototype machine were developed. The authors showed that the machine removes 95 percent of the stones. The machine efficiency was determined by new working bodies: a rotary frame, a comb and a special plow that cut a channel along the movement of the machine.

(Research purpose) To substantiate the design parameters of a mountain stone-harvesting machine and their impact on the grassland preparation quality. 

(Materials and methods) The machine was tested on the southern slope of the Dargavskoy Basin of North Ossetia-Alania at an altitude of 1650 meters above sea level, with a slope of 12 degrees. There were 9 options (3 in each repetition), each second option was a control one.

(Results and discussion) A method and a machine for removing stones with a diameter of more than 30 millimeters on slopes with a steepness of up to 12 degrees were developed. It was determined that stone clogging as the options were located from top to bottom averaged 37.2; 45.6 and 52.0 percent of the plot area.

(Conclusions) It was established that an increase in the pastures useful area due to the removal and utilization of stones made it possible to increase the load on 1 hectare of pastures, from 1.1 to 3.6 heads of feeding young cattle. The authors showed that the machine, along with the removal of stones, evenly distributed animal excrement, thereby increasing the productivity of fodder land: productivity compared to control increased annually by 0.33-1.93 tons per hectare.

Soil fertility can be restored using special technologies and equipment. In particular, chisels are developed for loosening lands with dense and gypsum soil layers, and mole drains are laid on saline lands with a high level of groundwater.

(Research purpose) To substantiate the parameters and technologies for using energy-saving chisel working parts for loosening dense and gypsum soil layers, as well as devices for forming mole drains in subsurface layers of saline soils.

(Materials and methods) Modern methods and devices were used to justify the parameters of the chisel ripper and the mole drainage tools. The authors presented the scheme of experiments at the pilot production area. They studied the mechanical composition and the degree of soil salinity in the experimental field.

(Results and discussion) The authors determined the soil loosening effectiveness before washing using the developed chisel cultivator. For laying mole drainage on heavily loamy highly saline soils a device was proposed that differs from its analogues in that it has a two-part frame.

(Conclusions) The authors ensured the high-quality execution of the technological process for the harmful salts removal from the fertile soil layers. It was found that soil decomposition with the chisel at a depth of 0.45 meters, and after plowing at a depth of 0.35 meters followed by soil washing, reduced the salt content from 0.978 percent to 0.198-0.578 percent, at the same time the desalinization coefficient was 1.7-4.9. The duration of irrigation was reduced by 15 days compared to traditional process. The authors showed that due to additional tillage in case of water shortage, the flushing rate could be reduced from 6500 cubic meters per hectare to 4500 or 5500 cubic meters. They determined that the application of the proposed technology reduced energy consumption by 9.0-14.5 percent, labor costs by 7.91-14.11 percent, operating costs by 8.16-11.0 percent, increased labor productivity by 16.3-18.0 percent, and that ensured annual economic efficiency in the amount of 11.6-12.6 million soums.

It is important to create foreign units alternative, introducing modern domestic technologies and lines in the framework of import substitution for the primary processing of strategic raw materials in the industrial hemp form.

(Research purpose) To substantiate the technological scheme of the line for processing industrial hemp into the hemp short, the characteristics of raw materials and low-cost fibers for the primary processing of industrial hemp in the form of tangled mass of incomplete length stems, harvested by a specialized combine.

(Materials and methods) Hemp rolls of spring harvesting were processed according to two options: single and double way of raw materials through the line, after which the hemp short quality indicators were determined.

(Results and discussion) The authors found out that hemp raw material had broken and tangled stems 36-470 millimeters long, of high separability, with a fiber content of 26-30 percent, but with a small breaking load of 13-17 kilogram-forces. They determined that the fiber yield with a single way was 28-29 percent, with a double way – 23-22 percent. It was shown that a double pass reduced the mass fraction of shives by 3-4 percent in absolute terms and reduced the breaking load by no more than 2 kilogram-force. A low content of defects was revealed: the mass fraction of shives was no more than 7.1 percent, the absence of a “paw”. However, due to the minimum breaking load of the fiber, hemp was assigned to the lower grade.

(Conclusions) The authors substantiated the scheme of small-sized and low-cost domestic line for the industrial hemp primary processing. They determined the quality indicators values of the hemp short and its output under various conditions of primary processing. The influence share of the second way through the line on the quality indicators was calculated: fiber yield – 97.3 percent; the breaking load of the twisted ribbon is 42.4 percent; mass fraction of shives – 75.3 percent; the average mass length is 61.2 percent; the weighted average linear density is 99.1 percent.

Sowing units are considered to be the most complex agricultural machines, as they perform many operations - both sequentially and simultaneously. At the same time, agricultural producers are interested in the high-quality operation of the units. For the high-quality execution of technological operations and the improvement of energy indicators, seeders it is important to know and improve their design.

(Research purpose) To determine the main agrotechnical and energy indicators of the seed drill for row sowing of SZD-4.0.

(Materials and methods) Experimental studies of the SZD-4.0 seed drill were carried out on winter wheat sowing at a soil moisture content of 8.4-29.7 percent in a layer of 5-10 centimeters, a soil hardness of 0.8-2.0 megapascals, the depth of a loosened layer fractions of 0-10 centimeters amounted to 48.0-53.2 percent. Energy assessment was carried out at three speed modes in an aggregate with an MTZ-80 tractor equipped with a dynamometer and a measuring recording system.

(Results and discussion) The main agrotechnical indicators of the seeder were revealed: the average depth of seed placement at the maximum, minimum and optimal depth of the coulters, the quantitative proportion of seeds planted at a specified depth, the height of the ridges after the passage of the unit, the number of seedlings and relative field germination. The authors studied the main energy indicators: the traction resistance of the seeder, the power consumption of the unit, the power spent on overcoming the traction resistance of the machine, the specific energy consumption of the unit, the specific fuel consumption during the main operation, the specific traction resistance.

(Conclusions) It was confirmed that when the speed of the unit was 9.5-13.5 kilometers per hour, the working bodies of the seeder provided the depth of seed placement, the actual seeding rate, and the quantitative proportion of seeds planted in the layer corresponding to agricultural requirements. They determined the optimal mode of operation: at a speed of 12.04 kilometers per hour, with a coulter depth of 54.6 millimeters and when loading the engine of an energy facility by 76 percent.

Effective cultivation of plants with grow light is possible only under optical radiation of a certain spectral composition. The cheapest way to generate optical radiation is with the help of high pressure sodium lamps. However, their spectral composition is not fully acceptable for grow light. LEDs allow you to set almost any spectrum, but their cost is quite high.

(Research purpose) To prove the spectral composition of the LED emitter-corrector used in grow light in addition to sodium lamps theoretically and practically.

(Materials and methods) The authors experimentally studied the effectiveness of combined irradiation in the Laboratory of Energy Ecology of Grow Light at the Institute of Agroengineering and Environmental Problems of Agricultural Production under the irradiation of Blagovest tomato seedlings. They investigated the biometric indicators of plants. The production experiment was carried out in the greenhouse plant Mezhvidi (Latvia) on adult Encore tomato plants for three options: the first – under sodium lamps; the second – with LED irradiators; the third – with a combination of sodium lamps and corrector. The effect of the irradiator on the plants was evaluated by the magnitude of the fluctuating asymmetry of bilateral signs of the leaf blade.

(Results and discussion) The authors found out that the use of the corrector improved the seedlings biometric parameters: increased the number of leaves, their wet weight, the content of chlorophyll and dry substance in them. It was noted that in the greenhouse the least favorable light environment was formed under sodium lamps, and LED irradiators created more comfortable conditions. They confirmed that the use of a corrector provided the best light environment. They revealed an increase in the yield of tomato fruits and their taste when using combined irradiation.

(Conclusions) The authors proved that to correct the spectrum of HPS lamp 400, a corrector photon flux of 71.2 micromoles per second is required, while the ratio of blue and far-red LEDs fluxes should be 64 and 36 percent respectively.

To reduce the damage level of wheat grains during its post-harvest processing, it is proposed to replace steel working parts in lifting and transporting machines with polymer ones.

(Research purpose) Experimentally determine the dependence of the degree of wheat grain damage on the number of collisions, the incidence angle and the hoisting-and-transport machines working parts surface material when the grain moves at a speed of up to 3.5 meters per second.

(Materials and methods) Experiments were carried out on a unit that reproduced the low-speed collision conditions of wheat grains with a smooth steel or plastic surface plate at various angles of incidence and the number of impacts.

(Results and discussion) The authors identified a significant reduction in grain damage in a collision with a plastic plate compared to a steel plate – by 8-10 percentage points – is observed only at incidence angles of 60-90 degrees and the number of strokes from 5 to 10. It was found that at incidence angle up to 60 degrees, the specified difference didn’t exceed 4 percentage points and reached zero at an angle of 45 degrees. The low efficiency of replacing steel working parts with plastic ones to reduce grain damage when driving at low speed was explained by the weak manifestation of the decrease effect in the potential energy of grain deformation upon impact on a plastic surface at a collision low speed.

(Conclusions) The authors determined that when grains moved at a speed of less than 3.5 meters per second in a rarefied stream without interaction between them, when individual grains collided with the hoisting-and-transport machines working parts, replacing steel working parts with plastic ones was impractical.

The authors analyzed the working process and design of the machines involved in grain cleaning. It was revealed that the energy intensity of universal air-sieve machines of domestic and foreign production is 0.86-1.61 kilowatt-hours per ton, the specific metal consumption is 30-700 kilogram-hours per ton.

(Research purpose) To develop a high-performance primary-secondary grain cleaning machine with low energy intensity, a high degree of purification of seed and food grain, as well as with the possibility of its installation in continuous grain cleaning and drying lines and complexes.

(Materials and methods) The authors created a new structural and technological scheme of the universal grain cleaning machine MZU-20D and its pneumatic system. A prototype was produced with a capacity of 20 tons per hour, with three pneumatic separating channels and three sedimentary chambers of the pneumatic system. They investigated the dust collector of the air system of the MZU-20D machine.

(Results and discussion) Using the finite element method, the calculated values and velocity vectors of the air flow at the nodal points of the dust collector cross-section were obtained. The louvered sieve with a porosity of 0.1 was installed at an angle of 30 degrees, in the presence of a dividing partition. The authors optimized the structural and technological parameters according to the three-level Boxing-Bencina matrix plan. Based on the results of the plan’s implementation, rational design parameters of the dust collector were chosen: the depth of the outlet pipe – 0.35 meters, the angle of blinds installation – 30 degrees, the blinds number – 8. It was determined that when the dust collector parameters were brought into line with the above values, the efficiency of the deposition of impurities in it reached 60 percent with hydraulic resistance of 260 pascals. During state tests of the MZU-20D machine at the SPK Rassvet in the Kirov region for cleaning rye grains of the Falenskaya variety, the following characteristics were confirmed: throughput – up to 20 tons per hour, installed capacity – 9 kilowatt, grain purity – at least 98 percent.

(Conclusions) It was established that the machine was efficient, performed the technological process qualitatively and could be used, for example, during reconstruction and development of new grain cleaning and drying lines and complexes.

The authors conducted an analysis of technological lines operation in the Russian regions. They reasoned the relevance of scientific research on the development and design of technological lines using modular equipment for the humic and complex fertilizers production. A technical problem unresolved from a scientific point of view was revealed – the lack of industrial production of specialized equipment for humic fertilizers obtained on the basis of deep processing of organic raw materials.

(Research purpose) To determine the optimal composition of modular equipment using digital technologies for the design of industrial processing lines for the organic raw materials processing (peat, sapropel, brown coal and biohumus) based on the technical specifications of the customer and the results of the experimental production lines.

(Materials and methods) The authors studied the efficiency of the technological lines based on their technical capabilities. They studied the practical results of checking the dependence of the obtained products quality on the parameters and operating modes of individual units and assemblies. They used well-known private methods developed on their basis.

(Results and discussion) The authors revealed some technical and technological deviations in the equipment operation: low level of organic raw materials purification when the vibratory separator was 85-90 percent, insufficient power of the disassembler – 3.5 kilowatts; fertilizers dispersion after the reactor exceeded 140 micrometers; the content of the ballast after filtration – 5-8 percent; the level of humic salts was low – from 5 to 10 grams per liter; trace element dosing system was not perfect. The authors suggested continuing the search for technical solutions for production without ballast humates using modular equipment. They identified the need to increase the productivity of technological lines from 1 to 2.5 tons per shift.

(Conclusions) Based on practical experience in modernizing production lines, the authors suggested optimizing the composition of modular equipment purchased in the market for engineering products. They determined the basic principles of the modular design of technological lines that allowed using the Internet portal to increase production efficiency and obtain a product of demanded quality.