The global biofuel industry is characterized by a wide range of legislative and regulatory measures for the development of bioenergy. In order to stimulate the production of biofuels, a set of measures has been developed, including legislative regulation, indicative planning of production volumes, preferential taxation and budget support. Ukraine is among the top ten largest consuming countries of energy resources. Weak and inconsistent state policy in the sphere of biofuels as well as inconsistent legislative provisions regulating activities in the field of production, circulation and use of biofuels, impede the effective development of the biofuel market in Ukraine. The purpose of this article is to determine the components of the system of state regulation of bioenergy and to identify effective mechanisms with regard to improving the legal regulation of the biofuel market in Ukraine. The management processes discussed in this article are provided by several methods, which particularly relate to the functioning of power structures and the end results or goals of the public administration system. Currently, there are significant inconsistencies in the formation and further functioning of the regulatory framework with the legislation of the European Union on the rational use of fuel and energy resources, the limitations of which increase due to inconsistencies between centralized and regional distribution. Therefore, further processes of effective economic development of Ukraine will largely depend on solving the problem of the sustainable provision of available renewable energy resources. Future development of the biofuels market in Ukraine will strongly depend on the institutional and legal conditions in the field of production, circulation and use of biofuels.

Indirectly or externally fired gas turbines (IFGT or EFGT) are interesting technologies under development for small and medium scale combined heat and power (CHP) supplies in combination with micro gas turbine technologies. The emphasis is primarily on the utilization of the waste heat from the turbine in a recuperative process and the possibility of burning biomass even "dirty" fuel by employing a high temperature heat exchanger (HTHE) to avoid the combustion gases passing through the turbine. In this paper, finite time thermodynamics is employed in the performance analysis of a class of irreversible closed IFGT cycles coupled to variable temperature heat reservoirs. Based on the derived analytical formulae for the dimensionless power output and efficiency, the efficiency optimization is performed in two aspects. The first is to search the optimum heat conductance distribution corresponding to the efficiency optimization among the hot- and cold-side of the heat reservoirs and the high temperature heat exchangers for a fixed total heat exchanger inventory. The second is to search the optimum thermal capacitance rate matching corresponding to the maximum efficiency between the working fluid and the high-temperature heat reservoir for a fixed ratio of the thermal capacitance rates of the two heat reservoirs. The influences of some design parameters on the optimum heat conductance distribution, the optimum thermal capacitance rate matching and the maximum power output, which include the inlet temperature ratio of the two heat reservoirs, the efficiencies of the compressor and the gas turbine, and the total pressure recovery coefficient, are provided by numerical examples. The power plant configuration under optimized operation condition leads to a smaller size, including the compressor, turbine, two heat reservoirs and the HTHE.

Ukraine’s commitments under the international framework agreements to reduce CO ₂ emissions and the Global Climate Change Initiative provide the basis for the implementation of bioeconomy mechanisms in the country’s Energy Development Strategy until 2035. One of the goals of this strategy is to reduce the consumption of fossil fuels and switch to alternative fuels. The agriculture of Ukraine is assigned the leading role in ensuring the replacement of fossil fuels with biomass of plant origin. The bioenergy potential of the agro-industrial sector of the economy requires extensive research in order to determine and integrate it into the country’s energy sector. The essential characteristics of energy efficiency in the context of the cluster model of organizing the activities of enterprises for the production of biofuel as stable interactions of geographically concentrated economic entities are investigated in this article. Peculiarities of introduction of bioenergy clusters as stable interactions of geographically concentrated business entities (enterprises, suppliers and organizations, including scientific institutions, etc.) have been determined according to a pre-defined and agreed development strategy for all participants without exception at the stage of formation of which the competitive environment is supported taking into account the energy, ecological and socio-economic parameters of the sustainable development of territories. A model of a territorial bioenergy cluster for the production of biofuels from crops and waste was formed and the advantages of creating bioenergy clusters were analyzed. Furthermore, a matrix of a PEST analysis of the formation of bioenergy clusters in Ukraine was formed.

The paper aims to consider the available policies for biomass output as a feedstock for further bioenergy production in post-war Ukraine in order to draw conclusions and learn lessons for the further deployment of bioenergy in Ukraine, and to define the number of jobs that bioenergy has enabled and could contribute in both Poland and Ukraine in the future. Poland has significant biomass potential, the lion’s share of which is agricultural crop waste, corn, and dedicated energy crops. Ukraine has a significant potential for the production and use of biogas and biomethane due to available feedstock and a developed gas supply system. The employment factor method was used to estimate the number of jobs in bioenergy in Poland and Ukraine. Assessments, which are the main result of the work, indicate that the number of jobs in agriculture for feedstock production for energy purposes may reach thirty-three thousand by 2030 in Poland and thirteen thousand in Ukraine. Agribiomass crop production for energy purposes in Poland is supported by the Common Agriculture Policy of the EU. Energy producers from biomass have priority access to the grid and qualify for feed-in tariffs, premiums and auctions, and special financial programs. In Ukraine, biomass energy producers may have a feed-in tariff for biomass and biogas and a 10% lower tariff for heat from biomass than the tariff for heat from natural gas. Despite the benefits of biomass, the installed capacities for its utilization remain insufficient due to the existing barriers in both countries.
In the future, Ukraine will need to develop its agricultural biomass sector more actively than before in order to substitute natural gas and other energy carriers.

Is the burning of woody biomass climate friendly?

The paper highlights calculations of bioenergy indicators when growing corn for grain and vegetable crops in Ukraine. The research results indicate the economic benefit of growing these crops for all the variants studied. Our research established that an increase in the bioenergy efficiency of the production of these crops is achieved due to the use of different rates of fertilizer application. The increase in productivity that was obtained as a result of the implementation of farming practices exceeds additional costs associated with the use of fertilizers. This confirms the economic benefit of producing these types of crops due to the enhanced bioenergy efficiency achieved through the optimal application of fertilizer.
The conducted research confirms the high energy efficiency of the bio-organic fertilizer (digestate) and the energy-saving technology of growing crops which were studied. High values of the coefficients of energy efficiency were also observed in the variants with the simultaneous application of mineral fertilizers (N90P90K90) and digestate-based bio-organic fertilizer “Efluent” (55.0 t/ha) on experimental sites of corn grown for grain (3.05–3.07), carrot (1.41–1.45) and red beet (1.97–2.00), but the cost of these variants also appeared to be the highest. Scientific research has used new methods and technologies for the effective processing of livestock waste in order to obtain organic fertilizer, which can be used to improve soil fertility and increase crop yields on the one hand, and biogas production as an energy-efficient process that has significant potential for producing ecologically clean and renewable energy on the other. The proposed approach to achieving energy efficiency helps to increase crop yield without increasing fertilization costs.

This article analyzes the perspective of implementing target indicators in the green transition of the agro-industrial complex of Ukraine. It is established that soil degradation has acquired a global dimension, and it has become a serious problem of a socio-economic nature due to the military actions in Ukraine. Analysis of the state of agricultural land was performed based on the following indicators: humus content in the soil, volume of application of organic and mineral fertilizers, pesticides, land area under organic production, etc. The purpose of the study is to assess the impact of implementing waste-free biofuel production technologies at the enterprises of the agro-industrial complex to achieve eco-goals of the European Green Deal. The article outlines target guidelines for achieving eco-goals of the European Green Deal. Further steps necessary to overcome current problems in compliance with the norms of the EU legislation on environmental protection at agricultural enterprises for the sale of agricultural products to European markets are proposed. It has been scientifically proven that the agro-industrial complex of Ukraine has an untapped potential for reducing greenhouse gas emissions through ecological modernization and implementing waste-free production technologies. It is suggested to use biogas plants as a promising means of solving the problems of waste disposal, improving the ecological situation, reducing energy dependence, and increasing soil fertility. The effectiveness of applying organic fertilizer, namely digestate, a by-product of methane fermentation, as biofertilizers at agricultural enterprises has been proven. Recommendations are provided regarding soil regeneration measures in Ukraine in the future.