The article proves that despite a significant growth in the service sector in recent years, industry remains the main engine of economic growth. Moreover, using the analysis of statistical data, it is shown that the development of industrial complexes of countries of the world is accompanied by corresponding structural changes, which in turn determines their economic development in general. The study aims to solve the following issues: which structure of the national industry can be considered progressive under modern conditions, i.e., can lead to progress and sustainable socio-economic growth; whether there is a correlation between the progressive structure of the country’s industry and its economic development and the quality of life of its population; how the approach of the country’s industrial structure to its progressive state influences the country’s economic development and quality of life of its population. The purpose of the study is to justify or refute the hypothesis about influence of progressiveness of the industrial structure on sustainable economic development and quality of life of the population. The main methods used in the study are cluster analysis and integral assessment. The statistical basis of the study is the data on inter-branch balances for 36 countries of the world for 2009, 2011 and 2014. The results obtained in the study allowed confirming the hypothesis about the positive influence of approach of the industrial structure of countries of the world to its progressive state on the sustainable economic development and quality of life of their population. This conclusion can be considered as the basis for forming the state policy of the world’s countries to develop their economies and improve the quality of life of their population.

The article proves that security of the national economy characterizes the ability of the country to withstand the destabilizing effects of various internal and external threats and to ensure its sustainable development. The study is carried out in the following stages: Diagnosing threats to security of the national economy → assessing the level of economic security of countries of the world → clustering countries of the world according to the level of economic security → modelling the impact of the national economic security on sustainable economic development of a country → forming measures to ensure security of a country’s economy. The basis for assessing the level of economic security of a country is a hierarchically constructed system of indicators, including composite, complex, and sub-indicators. The assessment of the level of economic security is carried out on the basis of international indices and rankings. The analysis of the correlation between the level of GDP per capita and individual indicators included in the composite indicator of economic security made it possible to identify those that should become the primary concerns of governments in order to enhance economic security as well as increase the level of GDP and ensure sustainable development of countries.

At the present stage, critical infrastructure is recognized as the main component of the national economy and the basis of both government and regional policy in the context of ensuring national security. Given this, the purpose of the present study is to generalize and systematize theoretical approaches to the interpretation of the concept of «critical infrastructure»; a closer definition of the essence and content of this term from the standpoint of recovering the national economy and ensuring the national security of Ukraine. As a result of the study, it is found that the concept of «critical infrastructure» is identified with such definitions as: infrastructure; life support systems; critical infrastructure objects; vital social functions; production, goods, services, and related processes. Using a systematic approach and a classification method, the interpretation of the term «critical infrastructure», which is proposed by various scientific schools, is conditionally systematized according to the following groups: system; elements of the system; structure (network, physical, organizational); aggregate of assets; security direction; key security task on the part of the State; object of protection (administrative, legal, cybernetic); component of national infrastructure; object of public administration; information security component, etc. The article provides the authors’ own approach to the definition of the concept of «critical infrastructure» as an aggregate of objects, systems, networks that are of priority and of strategic importance for the development of a competitive national economy and provision of an adequate level of national security, the neutralized or disrupted functioning of which may harm the national interests of the State, lead to the emergence of possible threats and risks, significant expenditures and losses. It is proposed to consider critical infrastructure as a scientific category from the standpoint of effective implementation of the priority security tasks of the State; ensuring the national security; increasing the level of resilience of the functioning of systems and infrastructure objects; risk management; implementation of the State policy in the field of their protection; recovery of the national economy.

Competition in electricity markets leads to volatile conditions which cause persistent price fluctuations over time. This study explores the problem of electricity pricing fluctuations in the DE-LU bidding zone from October 2018 to March 2022 by applying time series analysis. The determinants of electricity price fluctuations are broken down into three groups: exogenous prices (gas, coal and CO₂ prices), internal (consumption and generation) and external (net import between neighboring bidding zones) electricity flows. Based on the SARIMAX model, we tried to combine all these factors to forecast electricity prices in the single bidding zone. It was found that the SARIMAX (1, 1, 2) × (3, 1, 0, 7) model with exogenous prices, internal and external electricity flows, which has the lowest AIC and MAPE values, is the best-fitted model for the DE-LU bidding zone. Anonymous trading and unpredictable individual bidding strategies lead to persistent price volatility, which causes electricity prices to deviate from fundamental trends. To reveal the risk factors, the SARIMAX model of electricity prices needs to be supplemented with a GARCH model of the residual returns. For forecasting electricity price residual volatility in the DE-LU bidding zone, the SARIMAX model with exogenous prices, internal and external electricity flows must be accompanied with the GARCH (7, 0) model.

Ensuring the sustainability of the European power system is one of the key priorities in the implementation of the EU’s ambitious plans to become climate-neutral by 2050. The uniqueness of the power systems of the EU member states necessitates their assessment and comparison. The article offers a composite indicator, namely, the power system sustainability index (PSS index), to assess the current level of the development of the power systems via three dimensions (social, economic, and environmental) and eight local indicators: the household electricity consumption per capita; the commercial electricity consumption per GDP; the external dependency of the power system; the energy efficiency of the generation; the capacity utilization factor; the share of organic fossil fuels; the share of renewable energy resources; and the greenhouse gas (GHG) emissions per unit of primary energy source. The “energy mix” is defined as the key impact factor, which has a contradictory effect on the local power system sustainability (LPSS) indicators, which can be represented as a set of regression models. The data of the regression analysis can be used for performing a multiobjective optimization by the local indicators, and they can determine the vectors of change required to ensure the sustainability of the power system. The research results prove that it is possible to minimize the GHG emissions per unit of primary energy source and maximize the energy efficiency of generation, while reducing the capacity utilization and increasing the external dependency of the power system.

The creation of a single competitive EU energy market is aimed at establishing a fair price in the integrated market space. However, electricity markets in European countries remain rather fragmented, and the marginal pricing method, which is the basic one used in the market, conditions a persistent price dispersion in the search for market equilibrium. This study examines the dispersion of electricity prices in 40 bidding zones in 26 European countries by means of quartile analysis. The geographic orientation of the markets, direction of electricity flows, and structure of electricity generation are considered as the causes of this dispersion. In the study, the geographical boundaries of the electricity markets are determined using the methods of correlation analysis of prices and transitive closure of commercial electricity flows. This makes it possible to single out highly integrated, moderately integrated, poorly integrated, and non-integrated markets. Using cluster analysis, electricity markets are classified according to the structure of electricity generation and direction of flows, with the identification of five clusters based on the dominant type of generation and three clusters based on the dominant direction of electricity supply. For each factor under investigation, the intragroup price dispersion is established. The results of the study have allowed to build a three-dimensional matrix that provides for determining the directions of changes in electricity prices when moving between its quadrants.