General Energy Institute of National Academy of Sciences of Ukraine,  in cooperation between National Academy of Sciences of Ukraine and the International Institute for Applied Systems Analysis (IIASA, Austria), has been conducting scientific research, the results of which are used in the development of international projects, in particular, research climate change on the planet, since 2000.

Employees of General Energy Institute of National Academy of Sciences of Ukraine, in accordance with the joint project of National Academy of Sciences of Ukraine and IIASA "Complex modeling of management of the safe use of food, water and energy resources for the purpose of sustainable social, economic and ecological development", have been carrying out scientific work "Research of energy development processes as a factor sustainable development of the socio-economic system, ensuring its economic efficiency, technical reliability, minimization of the impact on the natural environment and GHG emissions since 2017."

As a result of the prospects of scientific and technical progress of the main classes of energy technologies search, the analysis of the regulatory framework that determines the principles of operation and the directions of long-term development of the energy sectors, forecast data of indicators for determining the marginal conditions of the economic efficiency of the main technological classes of the energy sector were formed. With the use of improved models of the life cycle of energy technologies, it was determined that the limiting conditions of the economic efficiency of the new promising technology of nuclear energy - low-power modular reactors - is to ensure the strategic direction of low-carbon energy development. A new simulated mathematical model for determining the optimal composition of a combined (accumulator battery and SES/WEP) power plant based on the criterion of economic efficiency is proposed. A new model of mathematical programming with integer variables has been developed, which allows for computer modeling of the processes of integration into the national energy system of significant volumes of generating capacity of renewable energy with stochastic nature of energy production, as well as with the preservation of energy generation by existing nuclear power plants. A balance-optimization mathematical model of the energy supply of the national economy has been developed in conditions of limited sources of energy sources, uncertainty of the forecast structure of the need for fuel and energy resources, environmental restrictions, taking into account the requirements of energy security, which involves observing the ratio between the volumes of imports and its own production, as well as the structure of the supply of imported fuel.

The following results were obtained during the performance of work under stage IV "Development of mutually coordinated systems of mathematical models of long-term sustainable development of energy as an infrastructural branch of the socio-economic system, modeling of typical scenarios" in 2020. In order to ensure the adequacy of the modeling of electricity generation modes by power plants that are part of the power system, mathematical equations have been developed regarding compliance with the required volumes of secondary reserves. The proposed equations application allows finding the optimal solution for the distribution of secondary reserves between the generating capacities of the power system for each hour of the electric load schedule. Such a solution ensures the maximum use of low-predictive forecasted capacity of renewable generation, wind and solar power plants, and thus allows for the formation of robust decisions regarding the technological structure of the electric power industry as a whole, both for the short-term and for the long-term prospect. The improved mathematical model takes into account the physical and technical characteristics of the generating equipment operating within the power system. Equations used as constraints of the optimization model are also developed in the model, which take into account the limit volumes of electric power flows with adjacent energy systems. Evaluating the level of flexibility of the power system under the conditions of its operation both in isolated mode (in this case, the power flows must be zero for each simulation period), and under the conditions of its operation in parallel with neighboring power systems is possible. The application of these equations significantly increases the adequacy of the model in terms of taking into account the impact of poorly forecasted capacity of renewable generation, wind and solar power plants, on the overall balance and reliability of the power system. The analysis of the new European documents on the decarbonization of the economy, in particular, the European Green Agreement, the Hydrogen Strategy for a climate-neutral Europe and the EU Strategy for reducing methane emissions, showed that they will have a significant impact on the functioning of both the energy sector of our country and non-energy sectors. In particular, the carbon border tax implementation  may make it economically unfeasible to export Ukrainian-made products to the EU, including electric power, due to the high carbon intensity of these goods compared to their European counterparts. The developed estimates of natural gas consumption for the period until 2040, taking into account structural changes in the economy of Ukraine and technological energy saving, predict a gradual increase in gas consumption from 31.5 billion cubic meters. m in 2017 to 44.2 billion cubic meters. At the same time, estimates of natural gas demand forecasts in the EU countries in 2040–2050 showed a tendency to decrease natural gas consumption. The policy of the European Union is the main reason for the decarbonization of the economy by reducing the consumption of fossil natural gas in the total consumption of gaseous fuel by replacing it with synthetic methane, hydrogen and biomethane. This defines the robust solutions to ensure the demand for gas fuel consumption at the expense of new low-carbon types of fuel to ensure sustainable low-carbon development of the economy.

Based on the results of the scientific work, a section of the collective monograph "Interrelationships in the food, energy and water system for sustainable development: integrated modeling and reliable management" was published in 2020 (ed. Bohdanova V.L., Yermolyeva T.Yu., etc.), which was published by the publishing house "Akademperiodika", 2 articles in a scientific publication indexed in international scientometric databases, 1 chapter as part of a collective monograph accepted for publication in 2021 published by Springer. The relevance of the conducted research and the obtained results meet international high-level standards.

The work is carried out in cooperation with leading specialists of such IIASA scientific projects as "Advanced System Analysis" and "Reduction of Pollutant and GHG Emissions into the Air" (academicians of the National Academy of Sciences of Ukraine M.M. Kulyk, S.V. Shulzhenko, T.P. Nechaeva, I. Ch. Leshchenko, M. I. Kaplin, V. V. Stanytsyna).

Employees of General Energy Institute of National Academy of Sciences of Ukraine in accordance with the joint project of National Academy of Sciences of Ukraine and IIASA "Complex modeling of the management of safe use of food, water and energy resources for the purpose of sustainable social, economic and ecological development" carried out the scientific work "Research of energy development processes in uncertainty information conditions  and growing environmental requirements regarding emissions of harmful substances and GHGs" in 2012–2016. The paper proposes a system of interconnected mathematical models of energy subsectors, which form an integrated mathematical model of the national fuel supply system with stochastic exogenous variables and scenarios. The existing mathematical models of the formation of directions of development of individual sectors of the energy industry, in particular, the electric power industry, coal and gas sectors, and the energy sector in general, have been improved and new mathematical models have been developed. Software and information tools for building stochastic scenarios of external conditions of the functioning and development of the energy industry, as well as technical and economic indicators of the main technological classes of the energy industry have been developed (academicians of the National Academy of Sciences of Ukraine M.M. Kulyk, S.V. Shulzhenko, T.R. Bilan, M. I. Kaplin, B. A. Kostyukovsky, I. Ch. Leshchenko, O. E. Malyarenko).

Employees of General Energy Institute of National Academy of Sciences of Ukraine in accordance with the joint project of National Academy of Sciences of Ukraine and IIASA "Evolution of high technologies, modeling and assessment of the impact of technological changes on economic development" carried out the scientific work "Research of directions and indicators of the development of the energy sector of Ukraine in the context of reducing emissions" of GHGs in the perspective of 2012 (post-Kyoto period)" in 2009–2011. The methods of limiting and regulating greenhouse gas (GHG) emissions at the interstate and national levels were investigated in the research paper, the options for possible restrictions on GHG emissions for Ukraine in the future were formed, and prospective directions and technologies for reducing these emissions were analyzed. The methods and means of forecasting the development of the energy sector have been improved to ensure taking into account restrictions on GHG emissions in the future and to assess their impact on the development directions of the country's energy sector in the future. Alternative scenarios for the development of the economic and economic sectors of Ukraine in the context of ensuring the fulfillment of the country's potential obligations regarding GHG emissions in the period up to 2030 have been developed and studied, taking into account the probability of a significant increase in the rigidity of the stated obligations in the future (Academician of the National Academy of Sciences of Ukraine M.M. Kulyk , B. A. Kostyukovsky, S. V. Shulzhenko, T. P. Nechaeva, O. O. Ruban-Maksimets, D. P. Sas).

The Institute in 2000–2008 conducted scientific research that is used in the development of international projects, in particular, research into climate change on the planet. Methodical approaches, mathematical models and software have been developed for researching the prospects of reducing GHG emissions, which allow determining the impact of the scale and pace of introduction of new technologies in the economic sectors on the level of GHG emissions. According to the project "Transboundary transport of air pollutants", the forecasting of the external conditions of the development of the fuel and energy complex of Ukraine was carried out taking into account the directions of transformation of energy markets, the directions of its development were studied within the requirements of environmental protection. Methodical approaches, algorithms and software were developed for the transformation of actual and perspective fuel and energy balances of Ukraine into the format of the RAINS (The Regional Air Pollution and Simulation) international model in order to obtain the possibility of clarifying data on the impact of thermal power plants on the environment (indicators of cross-border transfers of sulfur and nitrogen oxides , dust, greenhouse gas emissions). Prepared and submitted to IIASA management data for forecast calculations for the period up to 2030 using the simulation-inflation model of regional pollution RAINS, which allow to estimate for a specific scenario of the development of energy and agriculture, the cost and environmental effects of actions to control the admissibility of emissions; opportunities were analyzed and recommendations were made regarding the use of the mechanism for the implementation of joint implementation projects for ensuring investments in the development of the energy industries of Ukraine, provided for by the Kyoto Protocol (academician of the National Academy of Sciences of Ukraine M.M. Kulyk, B.A. Kostyukovsky, S.V. Shulzhenko).

The Institute employees, within the framework of the Technical Committee TK 48, cooperate with international technical committees on standardization (exchange of texts of standards, holding votes on the adoption of international standards in the field of energy saving)