The January issue of the International Scientific Journal for Alternative Energy and Ecology presents eight scientific papers by scientists from Uzbekistan, Montenegro, Azerbaijan, Russia and the EU.
The issue is devoted to topical problems of energy saving utilization of braking energy of vehicles, technologies for the production of methanol from straw and meadow grasses, hydrogen energy technologies: aspects of obtaining hydrogen gas during the decomposition of hydrocarbons in low-temperature plasma stimulated by ultrasound; biohydrogen production, hydrogen combustion processes in an oxygen environment, assessment of the possibility of hydrogen generation in a plant-microbial fuel cell; aspects of solar energy assessing the potential of solar energy for a particular region.
The material may be useful to scientists and graduate students working in the field of alternative energy and ecology.

Based on actinometric and climatic data obtained from the Guzar weather station (Kashkadarya) and satellite observations, an assessment of the technical potential of solar energy in the Kashkadarya region of the Republic of Uzbekistan was carried out. The indicators of solar photovoltaic power plants were studied in order to determine the forecast indicator of the replacement coefficient of traditional energy resources in the agricultural and irrigation sectors.

Exploratory studies have also been carried out to determine the generation of solar photovoltaic plants installed at various angles of arbitrary orientation

According to the data of the Ministry of Energy of the Republic of Uzbekistan, in the Kashkadarya region today, the actual consumption of electric energy is 891797 and 882174 kWh year (taken together 1773971 kWh year), for agricultural and irrigation facilities, respectively. According to preliminary confirmed calculations, the amount of conventional fuel saved from the use of solar photovoltaic stations to cover 50% of energy consumption (1773971*0.5=886986 kWh year) is 220 tons per year. At the same time, the specific saving of natural gas is 189 thousand Nm3 year, and the reduction of CO2 emissions during the year during the combustion of natural gas is 257 tons of CO2, respectively. It is established that if we take into account that the price of 1 ton of CO2 is estimated at an average of $15, the amount saved in the state budget for the year is $39000, including due to the saving of natural gas $35154 and due to the reduction of CO2 $3855, respectively.

The work is devoted to the creation of plant-microbial fuel cells (PMFC). A design of a cell for PMFC has been developed, which makes it possible to study the effect of the configuration and material of electrode systems on the values of bioelectric potentials (BEP) generated in the system root environment-plant. The possibility of using the developed technology for measuring BEP to create long-term plant-microbial fuel cells based on the use of plants electrical activity as an electromotive force is shown. The electrodes are made of various carbon materials and stain- less steel. The created experimental PMFCs are capable of generating voltages at the level of 230 mV in soil systems and 150 mV in hydroponic ones. The output power was about 50 mW/m2 at a load of 10 kΩ, which did not cause sig- nificant deviations in the condition of the plants. The calculated possible yield of hydrogen per m3 of the root envi- ronment was 0.4 mmol during the day. Thus, PMFC can become a promising source of green energy that can be combined with significant production processes for obtaining plant products or hydrogen.

The area of research is the experimental study of the composition of steam as a result of the combustion of hydrogen in an oxygen atmosphere in order to assess the underburning of hydrogen. The existing experience of experimental research on the combustion of hydrogen in an oxygen atmosphere is analyzed. Among the known works, the underburning of hydrogen was determined after mixing the dissociated vapor with a cooling component, which contributes to its sharp decrease in temperature. As a result, this leads to a decrease in the number of recombinations of unreacted hydrogen towards the formation of steam, which leads to an increased content of hydrogen in the steam. A large number of works are devoted to the combustion of various types of fuel with hydrogen additives in internal combustion engines in a number of European and Asian countries. The purpose of the article is to supplement and summarize a series of experiments on the study of hydrogen underburning when burning in an oxygen atmosphere without using a cooling component for mixing with combustion products (water vapor). Only external cooling of the flame tube of the experimental setup was used. This experiment was performed for the first time. For the conditions of experiments carried out by the authors of the article, a diagram, components and measuring instruments of the experimental setup are presented. The initial data on the pressure and temperature of hydrogen, oxygen, cooling water are given. The main expressions of the procedure for determining the underburning of hydrogen are given. The main results of experimental measurements are presented. The graphical results of measuring the steam temperature along the length of the flame tube of the experimental setup, the flow rates of hydrogen and oxygen, the temperature and flow rate of cooling water, the pressure inside the flame tube and in the steam extraction pipeline for chemical analysis are shown. On the basis of generalization of a series of experiments, an exponential character of the decrease in the underburning of hydrogen along the length of the flame tube of the experimental setup was obtained, which indicates the intense processes of hydrogen recombination towards the formation of steam. It was found that during the time of 0.069 s with the movement of dissociated steam inside a flame tube 980 mm long, the underburning of hydrogen decreases from 5.85 to 0.016% of the mass during stoichiometric combustion and to 0.0138% of the mass with an excess of the oxidant equal to 1.4.

In this work, experimental studies of the process of obtaining hydrogen and silver nanoparticles using intense ultrasonic cavitation affecting a plasma discharge in liquid hydrocarbons were carried out.

It was shown that ultrasonic action above the cavitation threshold intensifies heat and mass transfer processes in the treated medium, and in combination with an electric discharge, which contributes to the appearance of an ionized state of matter (plasma), such action is capable of decomposing complex hydrocarbon molecules to an atomic state with subsequent recombination and formation simple molecules.

Experiments on the production of hydrogen and nanoparticles were carried out on a special installation for the implementation of an acoustoplasma discharge in a liquid. The installation includes an ultrasonic generator, a piezoceramic transducer, a plasma discharge power source, a reaction chamber, and discharge electrodes.

The results of the analysis of gaseous reaction products by gas chromatography show that during the acoustoplasma decomposition of hydrocarbons, the formation of almost pure hydrogen (90-95%); the composition of the released gas also includes pairs of initial hydrocarbons.

Simultaneously with the production of a hydrogen-containing gas, the decomposition of hydrocarbons in a plasma discharge under the action of ultrasonic cavitation results in the formation of silver nanoparticles. The synthesized nanoparticles were isolated and studied using the method of transmission electron microscopy to determine the shape and size of the nanoparticles.

The study of the nanoparticles by electron microscopy showed that during the synthesis, particles are obtained, mainly spherical in shape. The size of the synthesized nanoparticles is 30–40 nm. It was also shown by electron microscopy that, upon aggregation, the particles do not become larger in size, but form compound associates. It is also important to note that the advantage of this method for the synthesis of nanoparticles is their activated surface, which has a high reactivity as a result of exposure to intense ultrasound.

The resulting nanoparticles and their agglomerates can also be used as functional materials, fillers, and components of composite materials.

The biological hydrogen production from confectionary wastewater (CWW) was evaluated in a continuous mode in up-flow anaerobic biofilters. Wastewater was pretreated in the vortex layer apparatus (VLA) for 1 and 3 minutes at a power of VLA of 14 kW. HRT in biofilters was gradually decreased from 5.6 to 1.8 and 1.3 days, which corresponded to OLR 2.0; 6.3; 8.8 kg COD/(m³ day). Pretreatment in VLA led to a change in a number of physicochemical characteristics of CWW: a slight increase in soluble COD, an increase in the content of soluble sugars, acetic acid, and a decrease in the concentration of propionic, butyric, and caproic acids. It was shown that due to the abrasion of steel needles in the pretreated CWW, the concentration of iron increased. Despite the fact that the highest yield of hydrogen was observed for unpretreated CWW, the pretreatment in VLA contributed to a significant increase in the methane yield, possibly due to an increase in the iron content in the pretreated CWW. Thus, pretreatment in VLA can be a promising method for improving the process of obtaining biohythane from wastewater.

Obtaining energy carriers convenient for storage, transportation and use for direct use in the energy sector, or lowenergy-consuming conversion at the point of consumption, into hydrogen fuel is one of the urgent tasks. Nobel Prize winner George Ola and his collaborators have shown that the universal product for large-scale industrial production of hydrogen is methanol, which requires the least energy costs for conversion.

However, the production of methanol from fossil fuels (coal, gas, oil) is accompanied by the emission of greenhouse gas carbon dioxide. This effect can be avoided by using fast-growing plant masses in carbon equilibrium with the biosphere as raw materials for its production (as much carbon dioxide was released during use, the same amount is absorbed during plant growth).

This paper substantiates the possibility of solving this problem with the help of a new technology for obtaining methanol from straw and hay of fast-growing meadow grasses.

A technological complex of installations for the production of methanol from straw and hay of meadow grasses is presented, including: a direct-flow reactor, a heater case with a fluidized bed of dispersed electrocorundum, a wasteheat boiler, an installation for removing excess carbon dioxide from synthesized gas with monoethanolamine and an installation for the production of methanol from synthesis gas and other auxiliary equipment.

The temperature in the reactor is 700 ° C, in the reactor heater is 800 ° C. The output of synthesis gas is 1.529 kg / s, its heat of combustion is 12939 kJ / kg. The share of synthesis gas entering to heat the reactor is 0.332 of the total output, and the production of methanol is 0.668 (1.47 m³ / s).

The power of the steam boiler-utilizer is 2219 kW. The yield of methanol is 0.56 kg / s, its heat of combustion is 20 mJ / kg. For the production of 1 kg of methanol, 1.78 kg of alfalfa is required. Annual consumption of alfalfa 31536 tons, water 16685 tons Annual production of methanol 17660 t. Thermal efficiency (gross) of the process of processing alfalfa into methanol 58%.

The work is devoted to the investigation of return mechanism of mechanical energy spent under transport facility barking lost during the transmission onto body and proportional volume loss of the engine fuel.

The mechanical energy output off the brake-wheel system is implemented by the cable, having the contact with the extra element between the body and rotating wheels. This extra element has got the additional weight that increases wheel system in insignificant volume and weight-only some %.

The other end of the cable is tied with a special spring storage of mechanical energy. Spring system of special construction is compressed by mechanical thrust force of the cable and there takes place the mechanical energy storage in the volume approximately 60-70 % of brake energy.

The Same brake end is also being tied with the overrunning clutch and return spring. Mechanical energy having been transmitted, the cable with the help of the return spring together with the brake disk (an additional element) freely comes back to the initial position. Mechanical energy storage has got the construction of spring made from high-quality steel. It is possible to create a construction storing the energy of all four wheels of transport facility with one spring. For construction investigated in the given work, the spring made of the carbon steel using the characteristics of the given steel, is chosen.

The electric generator set in the construction, mechanically connected with the mechanical energy storage transforms the mechanical energy into electrical by revolving the rotor under the spring action. The electric energy from the electric generator is directed for storing in the cell jars.

FIFTH INTERNATIONAL FORUM-SYMPOSIUM ON SAFETY AND ECONOMICS OF HYDROGEN TRANSPORT -WCAEE - IFSSEHT-2020 (DIGITAL)- CLARIFICATIONS AND EXPLANATIONS MARCH 18, 2022

SIXTH WORLD CONGRESS "ALTERNATIVE ENERGY AND ECOLOGY" - WCAEE-2022