The energy industry is the most important industry, the achievement of development goals in which leads to the country’s economic independence. Fossil fuel is used as the main source of energy. The burning of traditional fuels has a negative impact on the environment. At the moment, the use of alternative fuels in the energy sector is a promising direction. The use of biogas and biohydrogen is a potential replacement for traditional fuels in regions with a lack of electricity. An alternative gaseous fuel can be obtained from various organic raw materials (waste of animal and plant origin, such as cow manure, chicken droppings, corn silage, straw, lusk). Getting biofuels will allow you to build new energy systems that will generate electric and thermal energy from organic waste. In this study, the work of the GTU on various biofuels is considered with an assessment of performance indicators and emissions into the environment. To simulate the operation of the gas turbine installation, a mathematical model of the gas turbine engine was created in the GRAT AC software complex, and the mathematical model was identified.

   Previously, the authors substantiated the relevance of providing NPPs with base load in the context of their increasing share in the energy systems of Russia, according to the Strategy for the Development of Energy until 2035. As a solution to the problem, the authors proposed one of the options for providing NPPs with base load based on a combination with a hydrogen complex and an additional low-power steam turbine. In this paper, based on the norms and rules available in practice, as well as scientific developments of the authors of the article, two options for layout solutions for the main process rooms of the hydrogen complex are substantiated and capital investments in their construction are determined. The following layout options were considered: remote location of the hydrogen complex from the turbine hall with an additional turbine and relatively close location with underground and above-ground placement of the hydrogen and oxygen storage system.

   Electricity consumption is uneven during the day. NPP operation is most efficient in the mode of maximum installed capacity utilization factor due to high total capital investments with a low share of fuel costs. Electricity storage systems based on hydrogen technologies can be used to ensure high installed capacity utilization factor. The paper presents a comprehensive study of the hydrogen energy complex with a closed fuel cycle in combination with NPPs developed by the authors. Based on the adaptation of the methodology for comparative assessment of the efficiency of energy complexes at NPPs, a system of specific indicators has been developed. This system allows determining the comprehensive efficiency of power plants by adding up specific indicators characterizing the effects achieved during their operation in relation to the funds invested in them, including taking into account the savings of natural gas in the power system. In addition, a specific indicator has been developed characterizing the effect of reducing hydrogen underburning due to the implementation of a closed hydrogen combustion cycle. A comparative assessment of the efficiency of the hydrogen energy complex with a closed fuel cycle has been carried out, and the conditions for its economic efficiency have been shown. The main technical and economic indicators and conditions of economic superiority of the hydrogen energy complex over alternative options are determined. The advantage of the hydrogen energy complex in terms of accumulated net present value in comparison with the sale of electricity to the grid reaches 38.34 mln. $. With a 50 % increase in the cost of capital investments in the hydrogen energy complex, the high thermodynamic efficiency allows maintaining competitiveness in comparison with the sale of electricity to the power grid, but it is significantly reduced. The minimum value of hydrogen underburning, at which it is advisable to implement measures to reduce underburning, is determined, depending on electricity tariffs and the cost of measures to reduce underburning. Based on the calculated data obtained, an analysis of the effect of completeness of hydrogen fuel combustion on the specific efficiency indicators of the hydrogen energy complex is carried out. The specific indicator of the efficiency of measures to reduce underburning is determined. It is shown that even taking into account the increased cost of capital investments in the hydrogen energy complex, a competitive advantage is ensured in comparison with pumped storage power plants in almost the entire studied range of electricity tariffs and capacity charge.

   One of the promising ways to reduce the cost of low-power power products manufactured by atomic stations is the transition to combined production. This work presents the results of studies of the new technological scheme of the low-power nuclear power plant with a high-temperature gas-cooled nuclear reactor producing three types of energy products: electric and thermal energy, as well as hydrogen. Based on the results of mathematical modeling, it was found that the coefficient of the use of the heat of fuel of the proposed promising atomic energy complex reaches 78,7 %. In turn, the normalized cost of the joint production of hydrogen and heat is 12,3 % lower than the normalized cost of separate production of useful products.

   The dark fermentation (DF) process is of considerable interest for the production of biohydrogen from organic waste. However, industrial implementation of DF is still limited due to the insufficiently high efficiency of this process. In this work, the effect of different substrate feeding rates (1; 1,5 and 3 d-1, which corresponded to the time between loadings of 24, 16 and 8 h) in the DF bioreactor on the main characteristics of the process was investigated at a constant value of the hydraulic retention time (HRT) and organic loading rate (OLR) equal to 1 day and 24 g VS/(L day), respectively. To increase the overall hydrogen production rate and hydrogen yield, the substrate was pre-treated in a vortex layer apparatus (VLA). Hydrogen yield (HY), hydrogen production rate (HPR), hydrogen content (H2) in biogas and dissolved iron content in the substrate were the highest at a substrate feeding rate of 3 d-1 (8 h between substrate feeds) and amounted to 618 ± 225 ml/g VS, 14,84 ± 5,4 l/(l day), 54,8 ± 4,4 %, and 51,5 ± 38,9 mg/L, respectively. The main hydrogen producer in the microbial community (more than 80 %) was the genus Thermoanaerobacterium. Thus, it was demonstrated that the use of the highest feeding rate of the substrate (which corresponds to the shortest time between loadings) pretreated in the VLA provides the greatest stability and efficiency of the DF process. The obtained results are of significant importance for further improvement of the DF technology and can be applied when scaling the process in the future.

   Various types of plasma methods for producing hydrogen are considered. A hydrogen production unit based on quasi-stationary pulsed nonequilibrium plasma is described. The value of the percentage of hydrogen in the mixture obtained using a chromatograph is presented. The power introduced into the discharge circuit and the amount of energy spent on the formation of one hydrogen molecule are calculated. The energy for the formation of one hydrogen molecule is 5,1 eV. It was shown that hydrogen in the plasma-chemical reactor was mainly formed as a secondary product of the hydrocarbon synthesis reaction, since the amount of soot obtained at the outlet corresponds to 5% of the total amount of hydrogen obtained during the experiment. Thus, the efficiency of the unit from the point of view of low-tonnage hydrogen production, as well as the prospects for studying the possibility of synthesizing various hydrocarbons based on this plasma-chemical reactor, are proven.