Energy Security: A Conceptual Overview

Abstract

In a dynamically changing socio-economic environment with significant technical and technological progress, the notion of energy security takes on a new, broader meaning. Modern literature presents a variety of operational definitions of energy security. Most authors dealing with the issue of energy security expose its different aspects while standing in opposition to competing concepts. As a result, literature that addresses the problems of energy policy is becoming a platform for debates on the essence of energy security and the applicability of its various approaches to individual situations. There is no unanimity among authors with regard to the theoretical framework or the components of this notion. However, the issue of diversity of views is quite typical in social sciences and should not be taken negatively. Despite this, and perhaps contrary to the definitional wealth, experts in the field of energy policy constantly stress the necessity and urgency of undertaking work on the conceptualization of energy security. The aim of the article is a comprehensive review of the concept of energy security in the context of new trends in the development of the energy sector based on a narrative review of scientific literature. The main differences in the perception of energy security have been identified, and it has been pointed out that the “supply concept” of energy security is giving way to an approach in which energy is a factor initiating deep transformations of social systems by changing consumption patterns, reducing energy consumption, and forcing changes in economic systems by imposing energy efficiency standards and environmental standards.

1. Introduction

1.1. The Importance of Theoretical Conceptualization and Defining “Energy Security”

Despite the fact that the issue of energy accessibility has been present since the early stages of human development, the notion of energy security has long been neglected both in energy and security studies. The broader interest in the problem of conceptualization and subsequent operationalization of energy security has been reflected in scientific literature relatively recently.

Modern literature presents a variety of both conceptual and operational definitions of energy security. When reviewing individual publications, one can get the impression that energy security is a controversial concept, to say the least. There is no unanimity among authors with regard to the theoretical framework or the components of this notion. However, the issue of diversity of views is quite typical in social sciences and should not be taken negatively.

Current literature on energy policy provides a wide spectrum of definitions of energy security, which appear to explain the problem more precisely and comprehensively than competing approaches. Hence, literature is overwhelmed by the diversity of perspectives for explaining energy security. Most authors dealing with the issue of energy security expose its different aspects while standing in opposition to competing concepts. As a result, literature that addresses the problems of energy policy is becoming a platform for debates on the essence of energy security and the applicability of its various approaches to individual situations.

The diversity in perceiving energy security is influenced by a considerable diversity in the global scale of energy systems, economic conditions and public policies implemented under different political systems. This diversity of conditions causes a great variety of risks to which energy systems are exposed. As a result of these conditions, the concepts of energy security adopted by individual authors reflect different contexts and perspectives assumed by their creators [1].

The creation of conceptual bases, as well as the definition of categories and terms used, are the basis of scientific research in each field, as it allows communication of ideas and explanation of generalizations. Despite, and perhaps contrary to, the definitional wealth, experts in the field of energy policy constantly stress the necessity and urgency of undertaking work on the conceptualization of energy security [2,3,4]. Neuman [5] indicates that conceptualization involves the creation of abstract structures and the provision of definitions.

Definitions are formulated in order to draw conclusions and solve technical problems. They have cognitive and communicative functions in the first place. Concepts, in contrast, are like continua relations and visions of possibilities. Conceptual meanings are much more ambiguous and infinitely more versatile than tools. A concept is a continuum, and a definition tries to render it in distinct terms. Such a conceptual distinction is adopted in this paper.

Despite the differences between energy systems and their evolution over time, despite differences in the perception of issues and the perspective adopted, similarities with respect to threats to energy systems are a potential foundation for developing a universal concept of energy security. The underspecification of the concept of energy security prevents not only the communication of ideas, but also the formulation of effective public policies in the field of energy security. Booth [6] stresses the importance of conceptualizing the terms used in security studies, arguing that if we are unable to articulate something precisely, it is not to be expected that this will be achieved.

1.2. Purpose and Scope of the Study

Despite the fact that there are a great number of publications addressing energy security issues, only a few authors focus on the essence of energy security or analyze this phenomenon in terms of key concepts of energy security. Generally, there are no studies that comprehensively verify the concepts of energy security in the context of new trends in the development of the energy sector [7]. An additional difficulty is the fact that with technological progress and changes in the manner energy is produced and used, the concept of energy security will also change and evolve.

In view of the new conditions arising from technological progress, economic development, and the limitations of the definitional framework of energy security, the authors want to initiate not only a discussion in the scientific community but also in the economic sector that is implicated, that is aimed at conceptualizing energy security.

Hence, it is also possible to put forward a thesis: the existing definition of energy security is inadequate and does not cover the full framework in the dynamically changing reality, technical and technological progress, and geopolitical conditions, which makes many authors point out that it is an abstract, unknowable concept. Therefore, the conceptualization of the concept of energy security can better reflect the specifics of the issue.

The authors want to draw attention to the differences between the concept of definition and the concept of energy security. Conceptualizing the idea from different perspectives and defining adequate means of measurement are prerequisites for implementing energy security in the form of public policy.

1.3. Why Is “Energy Security” Important?

Since the dawn of time, energy in some form has been a key element in society’s life and development. Current civilization is dependent on energy to a far greater extent than it used to be. Energy shortages are a serious threat to the functioning of individuals as well as to society as a whole. Therefore, access to energy is a safety determinant in this respect. Like all resources, energy is a scarce commodity [8]. This means that energy resources need to be rationally managed in order to prevent the risks of energy shortages.

What is security in general? It is important to reflect on this issue since this idea is ambiguous; on the theoretical level, its essence is not considered often and is sometimes questioned. According to the Cambridge Dictionary, the term “Security” is associated with the protection of persons, buildings, or a country against threats such as crime or attacks by foreign countries. In people’s consciousness, and generally by scholars, the term “Security” is associated with “no risks” [9]. An investigation of the concepts of “Security” functioning in different areas of life can be an introduction to creating the concept of “Energy Security”.

In response to the risk of turbulence in the global energy system, both countries and international organizations take into account the challenges of energy security in their activities, currently linking them to economic and environmental issues.

It seems that Cherp and Jewell [10] explain the rationale for having a closer look at the problem of a conceptual approach to energy security very appropriately by citing their Energy Security Assessment Framework. Drawing up the framework for the concept of energy security is the starting point for further considerations. Identification of vital energy systems as well as identification of their essential features, in particular vulnerabilities of vital energy systems, are the next important steps in the assessment of energy systems. The steps outlined can provide a basis for the assessment of the safety status of energy systems and actions that follow the assessment, such as the implementation of a selected energy policy.

2. Materials and Methods

The authors carried out a narrative review of scientific literature with respect to the conceptualization of “energy security”. A narrative review is a study and discussion of the current state of knowledge on a given issue. The purpose of such a review is to show historical issues that can be applied to the present and can be used in the future. The use of this form of review was motivated by the flexibility associated with it. The mentioned flexibility was crucial in the search for a formula for the concept of energy security in literature, where these concepts are outlined very broadly. Although narrative reviews are generally not subject to a restrictive methodological process related to the topic studied, the authors applied an approach characteristic of more structured methodologies.

The first step of the study was to perform a preliminary search of the literature. The analysis of the reviewed literature began with the development of an algorithm of conduct when selecting papers best suited to the research subject from extensive (particularly in the recent period) references. The algorithm (Figure 1) was limited to searching the Web of Science (WoS) database. In general, we can distinguish two directions of research, i.e., ‘concepts, definition of energy security’ and ‘indicators of energy security’. In addition, these two criteria have been linked to concepts that narrow the search area, such as dimensions, country, region, and area. The review of the WoS resources in relation to such delineated phrases was carried out for two criteria, i.e., ‘topic’ and ‘abstract’.

The publications selected for analysis were divided into two time periods, presented graphically in figures (Figure 2 and Figure 3). Literature studies were carried out over a wide time span, but the detailed analysis included current literature from the last 18 years, with a distinction between 10-year and 8-month time intervals. The approach emphasizing the evolution of the concept of energy security over time had previously also been used by other authors [11]. The number of publications where the term ‘energy security definition’ appears in relation to the criteria adopted (Figure 2) is many times larger than the number of publications that address the problem of ‘indicator of energy security’ (Figure 3). An even greater diversity occurs in the set of accepted periods of analysis. The number of publications in the first period of analysis (2005–2014), in which the phrase ‘definition of energy security‘ occurs in connection with the restrictions, is 2.5 times lower than the number of publications in the latest period (2015 to 2022). This ratio decreases to 1.3 for the phrase ‘energy security concept’. For the term ‘indicators of energy security’, in conjunction with additional limitations, the number of publications searched increased, on average, four times in the period from 2015 to 2022. This represents a change in the range from 2.5 to 5, depending on the context. The greatest increase in the number of studies was recorded for the phrase ‘regional energy security index’. The above observations suggest that the focus of interest of scholars moves toward a discourse on the quantification of the level of energy security (a five-fold growth), which is a very important condition for the economic stability of countries and even regions of the globe.

A significant number of studies that deal with the issue of energy security and which potentially were within the scope of interest of scholars forced limiting the number of publications to be analyzed in depth to several dozen. The selection of individual publications was made based on an analysis of abstracts.

3. The Framework of Energy Security Concepts Outlined by Scholars

3.1. The Energy Security

In the first half of the 20th century, and particularly during the second World War, the concept of energy security was strictly related to securing supplies of fuel for the army. In the post-war period, the importance of supplies to the army, especially oil supplies, did not decrease. In addition, oil has become the primary energy carrier in many sectors of the economy in developed countries. Industrialized countries did not produce enough oil to meet their own needs. Hence, oil was imported mainly from developing countries. For that reason, energy security focused on securing oil supplies for a long time. In this regard, energy security was conceptualized by political analysts within a single strategy that merged peaceful diplomacy and war into a complementary whole [12]. Over time, the security of the oil supply became an important focus of interest for China, India, and other fast-growing economies, leading to increased competition for resources [13].

Such a perception of energy security in the second half of the 20th century was influenced by the significant dependence of the global economy (especially transport) on oil and its limited resources. In addition, the increase in demand from rapidly developing countries, especially China and India, can lead to increased price volatility and, as a result, long-term price increases. An additional risk factor in oil supplies is the concentration of most of the known resources in a small number of countries, mainly in the Middle East and in the countries of the former Soviet Union.

In the 21st century, concerns over energy supply, in addition to oil, have grown for the supply of natural gas. This problem mainly affects the Eurasian market. Concerns about the stability of supplies must be taken into account not only by consumers, but also exporters of energy raw materials. The economies of countries exporting energy raw materials are exposed to price fluctuations which destabilize their export revenues. Since the traditional challenges connected with ensuring a sufficient supply of energy carriers, especially oil and gas, did not change fundamentally, they remained at the heart of energy security programs in an unchanged form for the majority of the 20th century. Energy security is one of the fundamental conditions for economic development. As energy demand is growing much faster at the present stage of society’s development than in the past, energy security has become an indispensable component of national security. Owing to its key significance, energy security is an importance factor in shaping international relations [14].

3.2. An outline of the History of Contemporary Energy Security Studies

Energy has accompanied humanity throughout the entire history of development—from prehistoric times—and the importance of energy in this process is growing disproportionately with the increasing intensity of development processes. Thus, one can try to trace the concept of energy security on this path, although, in its early stages, it was not conceptualized for obvious reasons [15]. Studying the evolution of the concept of energy security can identify key aspects of this issue. The observation of evolution can help in assessing the sources of changes in the concept of energy security over time due to the impact of historical factors on the formation of analyzed trends in future periods [16].

In the early stages of human civilization, energy security was associated with ensuring access to flammable materials, mainly wood, without incurring excessive risks and expenditures exceeding the value of fire for a community. Hence, for thousands of years, the concept of energy security included three basic criteria:

• availability of sufficient supply of energy carriers,
• affordability of fuel sourcing (lower than the perceived value of fire),
• resilience of the energy supply system to external interference.

The indicated criteria (availability, affordability, and resilience), which are the basis for the creation of an energy security system, did not generally change until the middle of the last century. Although the basic paradigm of energy security has not changed, energy security strategies have evolved with the development of technology and economic development. In particular, the availability criterion changed. The main sources of the redefinition of availability were technological changes and technical innovations opening the way for new energy sources in lieu of fossil fuels. Availability was extended by intra-national and international trade. The criterion of affordability evolved, taking on short- and long-term dimensions. Within this criterion, a base-load versus peak-load distinction should also be made. With the increasing complexity of energy systems, the resilience criterion evolved not only to safeguard energy reserves but also to protect against external disturbances in power grids [17].

The essence of the concept of energy security, unchanged almost throughout the history of human civilization, underwent an accelerated transformation in the middle of the last century. The constantly increasing energy demand, satisfied with fossil fuels, led to environmental disasters, resulting in radical shifts in energy policy regarding primary energy sources [18]. In many countries, ecological damage caused by sulfur dioxide, nitrous oxide and particulate matter emissions led to regulations aimed at preventing pollution and reducing emissions. In retrospect, these early regulations may be seen as ineffective. However, the increasing tightening of emission standards, thus influencing the shape of energy policy, radically changed the bases of the concept of energy security. The elimination of fossil fuels from the energy mix was slowed down by the introduction of technological solutions reducing the negative impact of burning these fuels on the environment.

The hopes of the fossil fuel industry to maintain its position in the structure of energy production and consumption through technological progress were dispelled as a result of policies aimed at reducing the carbon footprint. In this context, concerns about pollution from the burning of fossil fuels gave way to the view that CO₂ emission connected with fossil fuels is the main source of the greenhouse effect and climate change [19,20]. Technologies for reducing pollution from the burning of fossil fuels did not prove sufficient to meet the CO₂ emission reduction targets. There were opinions that the high level of energy consumption put humanity under environmental constraints due to fossil fuels. Such a way of reasoning led to the suggestion that energy prices should rise and that economic incentives should be introduced so as to discourage the environment from exceeding the assimilation capacity [21]. Some authors suggested that the problems of climate change and excessive energy consumption cannot be solved without a profound transformation of social and economic systems, which would entail a large-scale reduction in the rate of production and consumption [22].

The concept of energy security in some form has accompanied civilization since its initial stages, but analyses in this area taking into account the principles of scientific research began only around 1975 [23]. Until 2001, publications on energy security were so rare that they were not even included in later reviews by some authors [11]. As the traditional concept of energy security did not change in the last century, most of the literature on energy security devoted to this challenge refers to the historical roots and traditional perception of the concept. However, there has been a considerable increase in interest in the concept of energy security in recent decades. This interest is accompanied by an increasing number of publications that show the shifting focus of studies. The scholars’ interests shift from ensuring the availability of primary energy carriers, through quantifying various aspects, to attempts at a more comprehensive conceptualization of energy security. The concept of energy security was continually extended to include further dimensions of this issue, such as risk elimination, the role of infrastructure, the role of national energy policies, and the issue of sustainable development. In addition to the security of supply, the latest approaches cover a wider context of energy use, such as energy efficiency, environmental concern, consumption patterns, and technological progress.

Following the inclusion of new dimensions to the concept, the definition of energy security constantly expanded. A decade ago, an alternative approach to conceptualization appeared, manifested by simplifying the definition to make it more widely applicable [24]. Simplification of the definition is justified until it covers all relevant issues. For example, the phrase ‘The freedom from disruption of energy supplies for whatever reason’ proposed by Čehulić et al. is an oversimplification, as it focuses solely on supply [25]. Also, the attempt to define energy security as an “assessment of different risks in the energy system” [26] is narrowing down to one important aspect. However, in general, neither the process of extending the concept of energy security nor the reduction of the dimensions of the concept of energy security was transparent.

3.3. Research Gaps in the Field

A relatively large number of publications dealing with energy security does not release this research trend from the problem of research gaps already signaled by various authors. Undoubtedly, such gaps should include scholars’ selective approach to the concept of energy security. Many of the papers to date refer to isolated aspects of energy security, such as technical, environmental, and economic aspects [27]. This leads to the omission of other important dimensions within a non-comprehensive concept. A considerable number of publications focus exclusively on a selected country [28], region [29], economic sector [30], energy technology [31,32], or chosen perspective [33], thus losing the value of universality.

Therefore, voices have been raised for over a decade supporting ideas of conceptualizing energy security based on a systemic approach [34]. Sovacool and Mukherjee [35], as well as Sovacool and Brown [36], also suggested an integrated approach in the search for a formula for assessing energy security using multiple indicators.

More than a decade ago, Goldthau pointed out the need to expand research into the integration of issues such as energy accessibility, energy security, and climate change [37]. Currently, with the explosion of papers addressing the problem of halting climate change, this is an even more urgent need.

3.4. Fundamentals of Conceptualization of “Energy Security”

In order to accurately communicate their ideas to the recipients, scientists need to show the presented issues properly. Definitions and explanations of the terminology are usually an introduction to a discussion. Irrevocably, understanding a given concept implies knowing its definition. Definitions and explanations of key concepts enable the content audience to synthesize knowledge on a given topic [38]. The use of conceptual definitions is intended to properly clarify and delineate the subject and scope of considerations [39]. Defining a given concept can be done by describing its characteristics and establishing the relationship between its components. The conceptual framework positions research within the methodological approach used and in a potentially broader context. At the conceptualization stage, two approaches to the problem need to be distinguished—the definition of a given concept and its operational definition. The conceptual definition of the term explains what the research subject is, and the operational definition clarifies how the research subject should be measured or described.

Neuman [5] states that a scientific definition should be unambiguous and have a clear and specific meaning. Baldwin [9] adds that defining the problem should establish relations with theoretically important aspects of the research subject. In addition, the conceptual approach should be operationalizable and enable empirical research. Ravitch and Mittenfelner [40] note that the conceptual framework established by the definition of a research problem can serve as a guide to identifying and selecting, and then integrating research theories. A precise definition of the research subject is also necessary for determining research questions, determining the position of the scholar, and drawing conclusions from the research material.

Despite the increasingly widely accepted, up to the point of universal recognition, the importance of the issue of “energy security” remains an ambiguous concept and thus probably still widely contested. So far, there is no consensus among energy policy scientists on the form of conceptualization of energy security. Currently, authors dealing with this issue in reviews cite several dozen definitions referring to various aspects of energy security [11]. If one were to collect all the definitions appearing in literature, their number would reach several hundred.

In the literature, one can notice a trend of growing interest in the operationalization of energy security, which translates into the search for effective ways to quantify this abstract problem. These interests are reflected in numerous publications discussing how energy security can be measured through the use of a wide range of indicators relating to various aspects of this phenomenon.

The hitherto efforts of a wide range of scholars have not led to forming a universal and widely accepted concept of energy security. Scholars point to the lack of a clear and coherent definition of energy security [41]. Definitions are conceptualized from different perspectives. Individual concepts are usually created in response to arbitrarily identified threats to energy security to analyze selected research problems. Individual concepts can also be based on contradictory assumptions.

After a review of the extensive literature, using a methodological criterion, three general and intertwining types of approaches to the conceptualization of energy security were distinguished for the purposes of this paper:

• concepts focusing on the security of energy supply (the 4As framework),
• quantification of various aspects of energy security (indices, indicators),
• contemporary (systemic) concepts.

Early concepts of energy security focused on the security of the supply of energy raw materials. From today’s perspective, they are difficult to consider as definitions or concepts because the security of supply is only a selected element of energy security. However, studies made in this convention are also still being published today.

Works addressing the problem of energy security quantification constitute a particularly broad class. They mostly focus on indicators signaling threats to energy security and the resilience capacity of the energy system [1]. Such works combine several indicators or develop a comprehensive indicator to support integrated energy policy-making, prioritization, thinking about risk factors, tracking energy security challenges over time, and facilitating the overview of the overall dependence. However, quantification should not be equated with an explanation, conceptualization or definition of the issue.

The idea manifested in the classification of energy security dimensions and their comprehensive perception is the basis for the conceptualization of modern works in this area. Such an approach refers to the essence of the conceptualization of energy security proposed by Cherp and Jewell [34]. The presented work is a search for threads contained in the proposals submitted by individual authors. Their (subjective) classification may be a recommendation for future works on the development of the concept of energy security. The article focuses on theoretical aspects of the concept of energy security presented in the literature on the subject. In view of the search for a general formula on this issue, which would be applicable in any country and in relation to the entire energy sector, the authors decided not to direct their work by referring a priori to any theory.

4. The Main Conceptual Frameworks of Energy Security

4.1. Traditional Approaches

Energy security is a very broadly defined concept, which takes on a special meaning from the social, economic and political perspective, with increasing consumption of energy, regardless of its form, which is characteristic of developed and developing communities. During periods of increased fluctuations in international energy markets, with different scales of impact covering selected energy carriers and groups of energy carriers, the concept of safety is of particular interest to many scientists. In the sphere of such a wide issue as energy security, it is obvious that many trends/directions of its consideration can be indicated. Among them, a traditional approach can be distinguished. In accordance with the adopted methodology, publications with a varied context of definitions that have been published recently (

Table 1. List of significant literature referring to the traditional concept of energy security.

Author (Year), Type of Study, Number of Citations (n)	Purpose of Research or Thesis	Methods, Period and Territorial Area of Research	Range of Definition
Tutak and Brodny [42], (2022), original work, (n = 8)	diagnosis of the state of energy security of the Three Seas Initiative countries, energy security indicators were selected in terms of energy, economic, environmental and social dimensions	Grey Relational Analysis (GRA) method	uninterrupted access to affordable energy sources, “guarantees of supplies of energy resources”, and “uninterrupted physical availability of energy carriers”
Mohammadi et al. [43], (2023), original work, (n = 63)	a complex indicator for the assessment of energy security and sustainable development for energy exporting countries; political and technological considerations were taken into account	standardized decision matrix of indices determined based on the Shannon entropy weights	reference to the International Atomic Energy Agency (IAEA) definition in the area of export, identification of threats to the energy industry, despite access to energy sources
Fouladvand [44], (2022), original work, (n = 2)	four behavioral attributes of collective energy security for heat	ABMS method (Agent-based modeling and simulation)	definition 4A for energy security in the context of conducted behavioral research
Thaler and Hofmann [45], (2022), original work, (n = 9)	lack of compromise between energy security, sustainable development and energy sovereignty for electricity	three scenarios using the triangle of energy targets for access to electricity	definition based on availability, accessibility, and affordability, sustainable development and energy sovereignty are the analogy of energy security
Thanh et al. [46], (2022), original work, (n = 2)	non-linear relationship between digitalization and energy security, energy security influences on digitalization	six indicators describing three attributes of energy security were selected: accessibility, affordability, and sustainability	availability, affordability and sustainable development of the energy industry are attributes of energy security
Chentouf and Allouch, [47], (2022), original work, (n = 0)	energy security assessment based on the Environmental Energy Security Index (EESI), including nine sub-indicators	index method	a secure energy system is stable, flexible, resilient, adequate
Axon et al. [55], (2021), review, (n = 19)	review of common attributes used in energy security definitions, creation of index sets and their scope	selection of publications based on the keywords: “energy security”, “risk*”, “measure*”, and “index” by country and region	definition of 4As in relation to safety and risk indices, components of risk and the role of risk in energy security, common features of energy security and sustainable development
Alemzero et al. [48], (2021), own research, (n = 87)	a complex energy security index for all energy systems, taking into account the largest energy producers and consumers	a method of complex indices in the economic, environmental, and energy supply aspect	energy security includes accessibility, affordability, along with technological development, sustainability and regulations
Štreimikienė et al. [49], (2022), own research, (n = 13)	taxes, environmental fees affect energy, environmental, and economic security as well as sustainability parameters	index method	energy security depends on the indices: production, distribution, turnover, energy consumption, energy efficiency, RES and CO2 emissions
Cox [50], (2018), original work, (n = 29)	assessment of the long-term safety of the national electricity system	three scenarios taking into account: market rules (MR), central coordination (CC), decentralization (TF),	energy security is an abstract concept which is difficult to define, and accessibility and affordability are its main attributes
Matsumoto et al. [51], (2018), original work, (n = 67)	the scope of the evolution of EU energy security in the area of energy supply was identified	three energy security indices based on the Shannon–Wiener diversity index were examined, a method for grouping time series	seven energy security attributes were specified
Ang et al. [56], (2015), review, (n = 426)	gaps were filled in the evolution of definitions and dimensions of energy security in terms of time	a study of the resources of scientific literature in relation to electricity	seven key attributes of energy security, social impacts, environment, management and energy efficiency were identified
Månsson et al. [52], (2014), review, (n = 170)	analysis of the methodology of quantitative assessments of the security of energy supply as well as identification of sources of uncertainty, their development over time and their impact on energy systems	a study of literature resources based on: energy availability, infrastructure, prices, etc., in the short period of time 2011–2013	polysemy of the concept of energy security, two interrelated dimensions were defined: physical—availability and reliability, and economic—volatility and affordability
Augutis et al. [53], (2012), own research, (n = 60)	integration of all indices into one complex characteristic, the so-called level of energy security	index method, aggregation of indices	definition based on modeling of economic processes, geopolitical situations, analysis of network reliability and resilience to disruptions, statistical failure of energy systems, risk analysis, energy supply issues, as well as technical, social, political and other consequences
Bambawale and Sovacool [54], (2010), review, (n = 70)	the socio-social aspect of the concept of energy security of Chinese energy consumers in various sectors	surveys	the energy security attributes include: security of energy supplies, geopolitics, climate change, decentralization, energy efficiency, research and innovation, new energy sources, technology, self-sufficiency, and imports

) [11,42,43,44,45,46,47,48,49,50,51,52,53,54,55] were selected for analysis. The research also took into account mutual relations (references), which were the basis for the definition of energy security in the basic studies.

Energy security in the traditional sense can be seen as a national or transnational security problem because securing steady supplies of fossil fuels, in particular, is crucial for the functioning of the economy and defense of the country or organization. At the same time, there are also concerns about the impact of fossil fuel exploitation on the environment and human health, which requires a more balanced approach to ensuring energy security in general. Many definitions of energy security provided by national or transnational agencies [IEA, OPEC, EC, APERC, and IAEA] are embedded in the traditional approach often referred to in the literature as the 4As [1,11,35,41,44,52,55,57,58,59,60], aggregated into four areas. In the 4As, i.e., the approach proposed by the International Energy Agency (IEA), energy security is defined by the following key attributes:

• Availability—the ability to provide steady and sufficient access to energy, both in quantity and adequate quality. It is physical access to resources of energy that can already be used in various forms in the energy system.
• Affordability—ensuring that energy costs are at a level that makes it accessible to all social and economic groups. This is connected also with the costs of the energy system and whether it is affordable for its users. The price of energy is the most common indicator of the affordability of specific system energy carriers. In this respect, there are many indicators, including the magnitude of investments made to improve energy security and the ability to bear costs.
• Acceptability—the ability to satisfy social needs and expectations in the field of energy security. This refers to the subject of public perception and support for various energy sources, which often involves social elements such as social assistance and environmental issues. In this context, attention should be paid to the social acceptability of various types of burdensome emissions into the environment, e.g., CO₂ emission from the energy system and investments to move away from fossil fuels.
• Accountability—ensuring the accountability of countries and other entities in the energy sector for their actions and decisions in order to ensure security. This means having sufficient access and the possibility to use energy sources to ensure equality within society (without exclusion). The quantitative diversity, as well as the diversity of energy sources and supply directions, provide the basis for minimizing the risk associated with supplies and ensuring access to this energy.

In the 4As approach, energy security is considered a comprehensive issue, which should not be reduced only to selected attributes, e.g., to the issue of energy availability. This definition requires consideration of many social, economic, environmental, geopolitical, etc. aspects. However, the completeness of the traditional definition of energy security is not a necessary condition for its applicability. In the literature on the subject, there are also scientific studies taking into account a different set of attributes, e.g., the 3As [1,45,46,48] or even the 2As [50]. Cox points out that accessibility and affordability are paramount for energy security. In contrast, Štreimikienė [49] provides a definition based on selected specific energy security indicators. In this paradigm, Štreimikienė is not isolated [54,61,62,63]. The various concepts of definitions presented, with a different range of attributes or characteristics, prove that the traditional approach to the energy security of 4As is no longer sufficient nowadays. Hence the rhetorical question: is it possible to define energy security, and can the definition itself close the framework of energy security? In a study on the evolution of energy security, Ang et al. [11] decompose the attributes of the traditional approach and put their own complete definition based on seven attributes, thus inspiring a discussion in the scientific community in the field. This way, energy security has become ubiquitous in discussions about energy management and climate change. Political documents, reports and scientific research equate this concept to uninterrupted access to energy sources, diversification of these sources, direction and volume of supply, resistance to external threats and energy self-sufficiency. However, the participants of this discourse also draw attention to the polysemicity of the term, or abstractness or indefinability [50,52,56,64]. In a dynamically changing socio-economic environment, with strong technical and technological progress, the concept of energy security takes on a new broader meaning, with a very extensive definition, which undoubtedly aims to conceptualize this security.

4.2. Analysis of Energy Security Threats—Index Approach

An analysis of energy security threats using an index approach involves the creation of a composite index that quantifies the various factors that contribute to energy security. The index can be used to assess the level of energy security in a country or region and to identify the specific threats that need to be addressed.

Many studies show that the nature of energy security has a multidimensional interpretation. Measuring energy security is a complex problem that can be conveniently tackled through the use of an indicator set [55]. It needs to account for the important physical, social, and economic characteristics. As energy security is difficult to measure using one simple measure, the various indicators are meant to accurately represent the different dimensions under study. Narula and Reddy [65] stated that individual indicators of energy security are insufficient to give a complete picture. It is often analyzed using a set of indicators (or metrics) that represent the various dimensions it encompasses based on a specific framework. Researchers have studied the dimensions, indicators, and values of energy security in their respective countries because of the context-dependent nature of energy security [35,66,67]. Significant differences among studies are observed in the way in which energy security indexes are framed and constructed [11]. Energy security is an evolving, interdisciplinary, and complicated concept. It must be considered with the effects of global markets, infrastructure networks, energy suppliers, financial markets, environmental, social and technological issues, and different national priorities, economic growth rates, geopolitical position, climate conditions, energy resources and demographic indicators [68].

The use of quantitative methods has become mainstream in energy security studies, especially in cross-country comparisons and long-term research [69]. The analysis covers not only energy supply but also comprehensive risks, including energy transportation and energy use [70]. Numerous research shows that there are visible discrepancies in determining the dimensions of energy security, and the selection of indicators corresponding to each dimension differs significantly. Also, the availability of data and the diversity of concepts and dimensions related to energy security can significantly affect the selection of energy security indicators. Commonly used indicators include energy consumption per capita, energy intensity, energy self-sufficiency, electricity prices, electricity supply, CO₂ emissions per capita, and CO₂ emissions [69,71].

In different studies, indicators are usually assigned to different dimensions. Energy security indicators are often set for individual countries or regions, but they are also used to assess institutions such as commercial companies, international agencies and universities. Each country has its own peculiarities and its own development strategy priorities, which change over time, so methods for determining energy security at the level of each individual country are reasonable. It should also be taken into account that it is not possible to develop a unique methodology that will be suitable for all countries. Each country has different energy resource wealth, economic growth, climatic conditions, demographic indicators, geopolitical location and the like [72].

The numerous indicators mainly focus on the complexity of the index. The more indicators an index uses, the greater the difficulty in collecting the data and conducting comparisons. A simple indicator generally focuses on a narrow aspect of energy security, while compound indicators cover more relative considerations in terms of analysis [70].

Energy security research can broadly be divided into two areas: studies that look at the issue from a spatial perspective and studies that examine it from a temporal perspective.

Among many methodological approaches presented in the literature, two main types of energy security indicators are identified: vulnerability-based indicators and outcome-based indicators.

Vulnerability-based indicators of energy security are used to identify potential weaknesses in a country’s or region’s energy system that could lead to supply disruptions or price fluctuations. These indicators include energy import dependency, geographic concentration of energy imports, energy storage capacity, energy diversification, infrastructure redundancy, and energy price volatility.

Outcome-based indicators of energy security are used to measure the actual performance of a country’s or region’s energy system in terms of its ability to deliver reliable and affordable energy to its users. They include mostly energy access, affordability, reliability, efficiency and sustainability. These indicators are important for assessing the overall performance of a country’s or region’s energy system and for identifying areas where improvements can be made to improve energy security.

Table 2. Indicators and measures of energy security.

Indicator/Index	Type of Energy Security Indicator						Source
	V	O	S	A	N	R
Global Energy Security Index		x		x	x		Azzuni, Breyer [73]; Criqui, Mima [74]; Turton, Barreto [75]; Umbach [76]; Wang, Zhou [77]
National Energy Security Index		x		x	x		China—Zhang et al. [78], Bamisile et al. [79], Wang et al. [80]; Pakistan (ESIOP)—Bin Abdullah [81]; Mexico (NESI)—Sanchez et al. [82]; USA (Index of U.S. Energy Security Risk) [83]; Singapore—Ang et al. [56]; European Union countries—Radovanović et al. [72], Obadi, Korcek [84]; Azzuni, Breyer [73]; Wang, Zhou [77]; Stavytskyy et al. [85]; Mara et al. [86]
Regional Energy Security		x		x	x		Wang et al. [87]; Zhang et al. [88]; Augutis et al. [89]
Aggregated Energy Security Performance Indicator (AESPI)		x		x	x		energy security level in Thailand Martchamadol et al. [90]; Pakistan and India Ali et al. [91]
Energy Security Physical Availability Index (ESPAI)	x			x	x		based on the measure of market concentration in competitive fossil fuel markets, Lefèvre [92]
Energy Security Price Index (ESPI)		x		x			based on the measure of supply flexibility in regulated markets, Lefèvre [92]
Energy Seurity Performance (ESP)		x		x	x		Sovacool et al. [35,36], Wu et al. 2021 (ESP for 125 countries) [93]
Conventional Energy Security Index (ESI)		x		x	x		Erahman et al. (2016) [94]; Koyama, K. (ed.), [95] 2011
New/National Energy Security Index (NESI)		x		x	x		Stavytsky et al. 2018 [61]; Sanchez et al. 2023 [82]
Energy Trilemma Index (ETI)				x	x	x	World Energy Trilemma Index (WETI) [77], World Energy Council [96]; Song et al. 2017 [97]
Supply/Demand (S/D) index		x		x	x		Scheepers et al. [83]; Security of supply (SOS)—Kruyt et al. [1]; Composite vulnerability index (CI) for security of supply for European countries- Badea et al. [98]; Energy vulnerability index for industrialised countries—Gnansounou, [99]; diversification in energy supply sources—Cohen et al. [100]; China’s energy supply security [101]; Cherp et al. [2] (supply oriented indicator)
Energy Security Performance (ESP)		x		x	x		Ha L. T., Thanh T. T. [102] 2022, seven indicators to reflect four aspects of energy security: availability, acceptability, develop-ability and sustainability; Erahman et al. [94]; global energy security performances Wu et al., 2021 [93]
Risk evaluation	x			x	x		Ziemba et al. [103], International Energy Security Risk Index (ESRI) [2], Global Energy Institute [76], Podbregar et al. [104], Chernyak et al. [105], Energy security risk index—Center for the Study of Democracy [106]; International energy security risk index- Stavytskyy et al. [61], Index of U.S. energy security risk [83,107]
Environmental Energy Security Index		x		x	x		Chentouf, Allouch [47]
Energy Transparency Index							World Energy Council [108]
Sustainable Energy Security Index (SES)		x		x	x		Narula, Reddy [65]
Model of Short-term Energy Security (MOSES)		x		x	x		Jewell [109]
Energy Architecture Performance Index (EAPI)—Energy Trilemma Index		x		x	x		a composite index based on a set of indicators divided into three basic categories (energy security, energy equity and environmental sustainability).

Type of energy security indicator: V—vulnerability-based indicators, O—outcome-based indicators, S—simple (disaggregated) indicators, A—aggregated indicators; Level: N—national, R—regional.

presents the main energy security indexes with their characteristic.

In observing the changes taking place in the proposed methodologies and the indicators used to measure energy security, it can be seen that earlier methodologies focused mainly on the security of supply, while over time, environmental and social aspects began to be included and taken into account as well.

It should also be mentioned that it is not possible to develop a unique methodology that will be applicative to all countries because each country has a different wealth of energy resources, different economic growth, climate conditions, demographic indicators, priorities, geopolitical positions and the like [72]. There is no single solution, and every country should use its own advantages and develop adequate policies that will support energy security.

4.3. The Contemporary Approaches to Energy Security Conceptualization

4.3.1. The System Approach to Energy Security

The bridge between traditional forms of conceptualization of energy security and its contemporary approaches is a trend linking energy security with the deregulation of the energy supply. The liberation of energy markets, intended by its supporters, was supposed to separate energy supplies from political motivations and any distortion associated with political motivations. The authors of this trend argued that markets are capable of supplying energy more efficiently and that the diversity of market participants can be a guarantee of security of supply. In place of the public good, treating energy as a market commodity led to questioning the idea of energy independence as potentially dangerous [110]. Relying on a market mechanism also means shifting the focus of energy security from physical availability to affordability. The concept of energy security inspired by economics was based on the planned design of the energy system instead of previously applied control over it. Building security consisted in estimating the possibility of the occurrence of different threats and the need to distribute the risk among different options of the energy mix.

However, creating the foundation for a systemic approach to energy systems should rather be attributed to Stirling, who, in his studies, relied on complex systems theories in relation to the management of risks associated with their utilization [111]. The author suggested diversification and systematic analysis of risks associated with the structure of the energy mix and systems in order to increase energy security. Cherp and Jewell [10] note that the scientific debate on energy security developed initially as a response to specific challenges such as the need to provide fuels for military purposes, the need to ensure electricity supply, or the need to ensure the efficiency of investments. As a result of this debate on energy security, three main perspectives of perceiving this issue emerged:

• derived from political sciences—the concept of sovereignty,
• rooted in the technical sciences—the concept of robustness, and
• derived from economics—the concept of resilience.

A selective methodological perspective characteristic of individual scientific disciplines leads to a differentiation of the concept of energy security. At the turn of the 20th and 21st centuries, although securing access to primary energy sources remained the focus, energy security ceased to be a purely geopolitical issue. Over time, the issue of energy security became so complex and interdisciplinary that it should not be considered from any single perspective. The links between the components of energy systems mean that considerations on energy security should refer to the entirety of the energy system instead of focusing on its selected aspects. It suggests the need to combine tools representing different methodological perspectives and to rely on different theoretical approaches to energy security issues in response to the interpenetration of particular aspects of the issue at different levels. Creating a single, comprehensive analytical platform is qualitatively different from addressing individual issues associated with energy security. Such integration requires overcoming the differences between theories and methodologies characteristic of different disciplines of science, such as engineering, political science, and economics. A comprehensive consideration of energy security issues also requires a simultaneous response to energy security challenges instead of solving them one by one.

In addition to the need for comprehensive problem-solving, the urgency to respond to energy security challenges is a factor that leaves a significant mark on energy policy. However, attempts to conceptualize the issue in an excessively broad manner led to the interpenetration of problems of economic efficiency, sustainable development, and energy security policy objectives, which made it difficult to quantify the issue [112]. The analysis of the concept of energy security in the literature shows that its definitions are polysemic in nature and may cover many dimensions and take on different specifics depending on the country, time range, and structure of the energy mix they are referred to [64]. Conceptual ambiguity creates analytical problems and makes forecasting and implementation of energy policy difficult.

Table 3. Topics raised in contemporary energy security studies.

Author	Year	Study Type	Research Method	Issues Raised	Type of Concept/Definition
Chester [64]	2010	original study	synthesis of various sources	polysemic nature of energy security, nature and underlying assumptions of energy security	energy security multi-dimensional nature
Keppler [110]	2007	report for EU Parliament	economic analysis	trade-offs between competing policy objectives: security of supply, environmental objectives, economic objectives	energy as a market commodity instead of a public good
Winzer [112]	2012	original study	case study	an attempt to narrow down the concept of energy security in order to limit the overlapping of the goals of energy security policy, economic efficiency and sustainable development	absence of protection from threats to the energy supply chain
Ciută [113]	2010	review article	descriptive analysis	normative and political problems related to energy security	review of the conceptualization of energy security in the literature
Sovacool, Brown [36]	2010	review study	meta-analysis	an analysis of energy security studies to identify dimensions of energy security	dimensions of energy security
Sovacool, Mukherjee [35]	2011	original study	synthesized mixed assessment	energy security as a multidimensional phenomenon, energy security should be considered in its essential dimensions	framework for analyzing national energy security policies and performance
Sovacool [27]	2013	original study	synthesized mixed assessment	energy security and sustainability concerns	country’s energy security index over time
Bar-Lev, Katz [114]	1976	original study	portfolio theory to fuel mix	fuels are no abundant resources and have to be conserved and efficiently utilized, risk diversification	optimization of fuel mix by applying a portfolio approach
Stirling [111]	1994	original study	information theory	need to diversify risks in energy systems	quantitative index of diversity
Stirling [115]	2014	working paper	risk management analysis	understandings of socio-technological potentialities may reduce the vulnerability of societies and ecologies	reflexive governance of technological vulnerability
Cherp, Jewell [34]	2011	original study	system analysis	an attempt to find integrated solutions to multiple energy security threats	interdisciplinary approach
Azzuni, Breyer [41]	2018	systematic review	structural dimensionalization	dimensions and parameters of energy security	categorization of parameters of energy security
Axon, Darton [55]	2021	original study	risk analysis research	uncertainty, handling of risk, methodological rigor and consistency in the development of frameworks in energy security analyses	methodological suggestions in energy security analyses
Ang et al. [56]	2015	review article	quantitative methods	energy availability, infrastructure, energy prices, energy efficiency, governance, societal effects, environmental sustainability	methodology of energy security quantification
Novikau [116]	2022	review study	content analysis	energy security, security studies, security of supply	identification of the main energy topics covered in the literature
Couder [117]	2015	review article	system approach	vital energy systems, attributes of energy systems, threats to the energy systems, dynamics of energy security, energy efficiency and energy security	a framework of energy security assessment
Naess-Schmidt et al. [118]	2015	research project	economic analysis	quantification of the multiple non-energy benefits of energy efficiency	economic impacts of energy efficiency
Thema et al. [119]	2019	original study	cost-benefit analysis	energy efficiency has multiple benefits, energy efficiency impact assessment, energy security, energy efficiency macro-economic impact	energy efficiency has multiple impacts
Hassan et al. [120]	2021	original study	quantitative methods	energy efficiency as a remedy to the problem of environmental pollution	energy efficiency impact
AGECC [121]	2010	UN’s Report	political analysis	a summary of global energy challenges, including energy security challenges	recommendations for achieving social and economic goals
COM/2010/0639 final [122]	2010	Communication to EU Parliament	political analysis	strategy for competitive, sustainable and secure energy	energy policy recommendations, EU-level energy policy should be developed
Fell, Kaffine [123]	2018	original study	quantitative methods, regression methods	impact of natural gas prices and wind generation on emissions	significant interaction between gas prices and wind generation
Gugler et al. [124]	2021	original study	economic analysis	effectiveness of climate policies, carbon pricing, subsidizing renewable energies	carbon pricing is superior to subsidizing RES
Yao, Chang [125]	2014	original study	quantitative and qualitative evaluation	assessment of China’s energy security over a 30-year period, availability of energy resources, the applicability of technology, societal acceptability, affordability of energy	suggestion to develop renewable energy resources on a large scale
Mbonye et al. [126]	2022	systematic review	exploratory analysis	sustainable energy for attaining sustainability development goals, smart grid in delivering universal electricity access, smart grid security threats	integrated model of threats to the security of smart grids
Leal Filho et al. [127]	2022	review study	exploratory analysis	links between renewable energy (RE) and energy security	major disadvantages and potential of RES solutions
Motlagh et al. [128]	2020	review study	recent literature systematic search and review	modern technologies such as the Internet of Things applications in the energy sector, optimization of energy use and sustainable energy transition, challenges of deploying IoT in the energy sector, including security	applications of IoT in the optimization of energy system
Alsuwian et al. [129]	2022	review study	various techniques and approaches	smart grid cyber security, Internet of Things (IoT) for an intelligent energy system	incorporation of communication technology into the smart grid
González et al. [130]	2021	review study	systematic literature survey	novel information and communication technologies in the electricity distribution network (smart grid), energy-relevant parameters of the grid optimization	current challenges and outlook for the field
Ante et al. [131]	2021	review study	co-citation analysis	blockchain technology in energy networks, energy market transformation through blockchain technology, energy management in smart grids, peer-to-peer energy microgrids	research directions derived from the surveyed literature
Perez-De La Mora [132]	2021	review study	bibliometric analysis	microgrids as a distributed and embedded energy production alternative	energy security via microgrids, energy storage systems and local energy markets
Bharathidasan et al. [133]	2022	review study	compilation of original sources	energy transition, carbon-neutral and renewable integrated civilization, integration of electric vehicles powered by renewable energy sources, cyber security	technical recommendations
Le, Nguyen [116]	2019	original study	panel data analysis	linkages among energy security, energy for economic development, and climate change mitigation	energy supply, energy security and climate change mitigation should be considered in an integrated way
Wang, Wang [134]	2020	original study	decoupling model, decomposition approach	decoupling of economic growth from carbon emissions growth through the energy transition	energy transition needs to be accelerated to achieve economic growth
Nepal, Musibau [135]	2021	original study	econometric modeling	linkages between energy security, renewable and non-renewable energy on economic growth	the long-run relationship between energy security and economic growth for ASEAN
Valentine [15]	2011	original study	critical analysis of the energy security concept	the symbiosis between energy security and renewable energy sources	renewables increase energy security
Ren, Sovacool [136]	2014	original study	fuzzy AHP strategic measure	ranking of the importance of Chinese energy security factors, factor threatening China’s energy security, renewable energy, and energy technologies aiming at improving energy efficiency	identification of the effective strategic measures for enhancing energy security
Edenhofer et al. [137]	2013	original study	economic analysis	economic aspects of renewables that are relevant to the design of RE policy	recommendations in the field of RE policies
Khan et al. [138]	2022	original study	econometric modeling	impact of energy balance and clean energy transitions on economic expansion and environmental sustainability	clean energy transitions improve while natural resources depletion deteriorates environmental sustainability
Al-Shetwi et al. [139]	2020	review study	content analysis	integration requirements and compatibility of RES power plants with the power grid, grid integration of RESs, the design and control strategies	review of solutions for compliance technology and control methods
Noussan et al. [140]	2021	review study	descriptive analysis	challenges and opportunities related to green and blue hydrogen	opportunities to mitigate climate change and enhance energy security
Smith Stegen [141]	2015	original study	political analysis	the threat of a deficiency of rare earth elements for renewable energy technologies	critical evaluation of the ‘rare earths’ elements problem
Edwin (ed.) [142]	2022	book	mix of methodologies	issues related to clean energy transformation	recommendations related to clean energy transformation
Papadis, Tsatsaronis [143]	2020	review article	descriptive analysis	climate change mitigation, reduction of CO2 emissions related to the energy sector, global carbon tax as an instrument accelerating the decarbonization process	emission reductions by using appropriate technologies and policies
Grigoroudis et al. [144]	2021	original study	mathematical modeling	energy sustainability, the essence of energy, limited energy resources, energy externalities	mathematical model of energy sustainability
Jie et al. [145]	2023	original study	econometric methods	impact of socio-economic development and of sustainable energy policy on the ecological footprint	sustainability is a long-term result of socio-economic development
Lesage et al. [146]	2009	original study	political science	energy challenges need to be tackled through global energy governance (GEG)	an assessment of the G8′s value added in GEG
Van de Graaf, Colgan [147]	2016	review article	review of the GEG literature	goals and rationale of global energy governance (GEG)	progress and limitations of GEG literature
Valdes [148]	2021	original study	international political economy	concept of energy security within the global energy governance literature	governance of the energy security as transnational public good
Overland [149]	2019	original study	geopolitical analysis	consequences of the energy transition, materials critical for renewable energy technologies	shifting the focus from fossil fuels to renewable energy sources
Vakulchuk et al. [150]	2020	review article	no theoretical framework	renewable energy and critical materials, security risks and geopolitical tensions related to materials for renewables	renewable energy exacerbates threats and geopolitical tensions around critical materials and cyber security

presents selected studies associated with the conceptualization of energy security. It is impossible to present all relevant works in this area due to the abundance of literature. The studies presented here have made a significant contribution to the discussion on the formulation of the energy security concept or are characteristic of a given type of approach to this issue. However, their selection is arbitrary. The papers collected in the table are arranged thematically, and to some extent, chronologically within individual trends, to signal their evolution.

The traditionally understood conceptualization of energy security was essentially two-dimensional (availability/affordability). Modern concepts are generally much broader and take into account additional dimensions, such as the environmental dimension [116]. Debates on energy security reflect the calls for decisive and rapid actions to decarbonize energy systems while ensuring universal access to modern forms of energy for the general public [121]. At this point, it is worth noting that the energy policy objectives declared a decade ago have changed fundamentally due to climate challenges. For example, in 2010, EU documents defined a common goal of the EU energy policy as ensuring that energy products and services are available at an affordable price to all consumers while contributing to broader social actions and climate objectives [122]. Current EU actions point rather to priority being given to measures to stop climate change, which has far-reaching implications for the concept of energy security.

Almost all over the world, the profile of electricity generation has been evolving in recent years. The share of electricity produced from coal is decreasing, but in some countries, the declines in natural gas prices in previous years led to considerable increases in the share of this fuel in electricity generation [151]. There are not many studies in the literature assessing empirically the effects of climate policies [123]. Currently, the issue of particular interest is the problem of climate efficiency of policies, such as direct subsidies for RES and the valuation of CO₂ emission rights [124].

Despite certain differences on a global scale, the results of empirical research suggest that the problems of energy security, economic development, and climate change mitigation should be investigated in an integrated manner due to the interlinkages between these issues. On the other hand, energy security is positively correlated with economic growth [152]. This positive relationship is demonstrated regardless of whether energy security is based on traditional or renewable energy sources [135].

Technology is inextricably linked to the production and use of energy [125]. Therefore, directly and indirectly, energy security is strongly conditioned by technological progress. Technological advances make it possible to use new energy sources. For instance, advances in electrolysis have expanded the energy system to include an alternative energy carrier, hydrogen. New technological solutions in the field of production, processing, storage and distribution have the potential to increase energy security. Electric cars are becoming an important complement to the modern energy system, enabling its stabilization [133].

In recent years, there has been a growing trend in literature, namely works pointing to synergies between technological development, which allows us to reconcile the challenges of the need to ensure access to energy with the demands of sustainable development. At the same time, these works raise the problem of technical challenges with the prevention of threats to the functioning of modern energy systems in the form of, for example, smart grids [126]. A smart grid integrates multiple energy sources and is supported by a control and communication network using the Internet of Things to create a more reliable and intelligent energy system. However, such a system is facing new challenges connected with integration, security, interoperability, and data management [128,129]. Modern technologies (e.g., blockchain technology) show the potential for transformation of the energy sector and its optimization [131]. The development of technology has resulted in the emergence of microgrids as a distributed alternative to energy production. A new type of energy market has emerged—peer-to-peer energy trading as a concept for the exchange of renewable energy produced by prosumers [132]. Thanks to innovative information and communication technologies that comprise smart grids and homes, a modern electricity distribution infrastructure is being created to ensure energy efficiency in such systems [130]. This innovative infrastructure is put at the disposal of a new type of user—prosumer. It is expected that the tendency of decentralization of energy systems will continue. Security remains a major concern for smart grids and will require special attention in the future.

With increasing CO₂ emissions combined with climate change, there is increasing pressure on political decision-makers to implement clean and renewable energy technologies. The energy transition can not only reduce greenhouse gas emissions but also potentially increase energy security and boost economic growth [153]. The problem of the role of non-traditional energy sources in the concept of energy security is not perceived unambiguously in the literature. A broad transition to renewable energy is still a matter of the future. The full benefits of this transformation will only be felt within several decades [150,154]. Technological progress in the field of RES increases supply and results in easier access to energy. On the one hand, RES has for some time been seen as a means of ensuring energy security in the future [136], but there are less optimistic opinions regarding such a perspective [137]. In the area of RES, more and more countries are working on national hydrogen strategies. Currently, the greatest interest in this technology is in Asia and Europe [140]. The fast development of the renewable energy industry raises voices suggesting an inevitable competition for the raw materials necessary for these technologies [141]. Most of the concerns relate to the 17 rare earth elements necessary for renewable energy sources [150].

Supporting the idea of a positive impact of renewable energy on energy security seems obvious in countries with lower levels of development, with poorer infrastructure, and without access to energy resources, where renewable sources can fill the gap created by their backwardness. In addition, renewable sources have the potential to support such societies in their energy transition and reduction of their carbon footprint [127,142]. The authors of this trend argue that further reliance on conventional energy technologies has an adverse effect on energy security [15] and that renewable technologies provide greater energy security. Despite the obvious risk of geopolitical competition for materials that are critical to renewable energy, the authors argue in favor of searching for positive solutions in this area [149,155].

At a time of considerable variability in fossil fuel prices and growing concerns about environmental pollution, energy efficiency has become an additional important factor influencing the shape of energy policy [120]. The scarcity of resources of primary energy carriers and the need for their efficient use had already been pointed out several decades before such a trend of research on energy policy was clearly crystallized [114]. The review of numerous definitions of energy security leads to the conclusion of their contextual nature and growing interest in the issues of environmental sustainability and energy efficiency [11]. The effects of energy efficiency improvements can be grouped into two categories: short-run effects (business cycle) and long-run (structural) effects [118]. Studies in developed countries suggest significant energy cost savings (around 50–70%) and the possibility of GDP growth of around 1% thanks to increased energy efficiency [119]. Key impacts of energy efficiency for energy security are achieved through the impact of energy efficiency policies [117].

Energy determines all kinds of economic activity. However, its resources are limited, and, in addition, energy creates external effects [144]. Alongside energy security and economic stability, environmental sustainability is seen as one of the dimensions of the energy sector [143]. An increasing number of studies are highlighting that the condition for creating solid bases for prosperity and competitiveness is the balancing of the three aspects of energy: affordability, energy security and environmental sustainability [138]. Sustainable development in the energy sector determines the ability to meet the growing demand for energy and reduce the global carbon footprint. The energy system can focus on environmental objectives to accelerate decarbonization [143]. Some studies clearly articulate the connection between economic growth and environmental burden but also point to a positive long-term relationship between socioeconomic development and sustainable development [145]. The number of works supporting the views on the need to include sustainability issues in the concept of energy security has been growing dramatically in recent years.

The evolution of energy systems has led scholars to treat energy security issues in an integrated manner and to link them to issues such as universal access to energy and climate issues. Therefore, there have been threads substantiating the creation of mechanisms of energy management at the level of the country, then of international organizations and groups, and in the next step at the global level [147]. The term global energy governance (GEG) emerged in about the same period as the G8 picked up the theme. One of the first uses of the term GEG took place in the context of the G8’s work on energy [146]. Increasing concerns about energy security stemmed from the trend of rising oil prices, geopolitical turmoil, and motivation to fight climate change. These original motivations for shaping the global energy order quickly gave way to concerns about energy security on the way to the transition of energy and its coordination on a global scale [148]. Hence, energy security was treated as a public good, which generated implications for global energy management. However, some authors noted that the extension of the public character of energy security might limit collaboration in climate change mitigation.

4.3.2. Concluding Remarks

Contemporary literature on energy security is moving away from investigating isolated problems such as the issue of ensuring oil supplies, the issue of securing electricity supplies, the problem of security of transmission networks, and the issue of energy transformation in favor of an integrated approach. This implies the need to look for forms of comprehensive solutions of safety issues for integrated energy mixes based on various energy sources. Conceptual frameworks generally articulate ‘dimensions’ or ‘aspects’ of energy security [117]. Contemporary concepts of energy security are no longer focused on securing the supply of primary energy sources, but they expand the security issues to environmental, social, and economic issues and the operational reliability of energy systems.

Some papers provide arbitrarily prepared lists of risks to the functioning of energy systems. The author’s contribution to the development of research ought to be appreciated. However, the value of such lists for universal concepts is limited due to the specificity of energy security challenges depending on the country or structure of the energy mix. The hazard classifications presented in literature rarely have a consistent justification and, therefore, can only be a starting point for scientific description and understanding of the essence of energy security.

The number of publications attempting to conceptualize and define energy security is impressive. The plethora of definitions reflects the lack of unanimity in the scientific community regarding the essence of the concept. From a historical perspective, definitions were initially relatively general and simple but adequate to “their times”. Over time, a trend has been emerging to include other dimensions in the definition, which causes complexity and excessive expansion of the created concepts. The scholars’ answers to this fact are attempts to simplify the concept of energy security and specify the terms used.

Table 4. The essential dimensions of energy security concept in contemporary literature.

Dimension	Aspects
Availability	resources, means of transport, infrastructure, energy markets, diversity of resources, diversity of technologies, fuel conversion, energy cost (affordability), energy consumers, timeframe (long-term/short-term security), interconnection network of energy systems
Resilience	the adaptive capacity of the energy systems
Energy efficiency	energy system efficiency, energy conservation, energy intensity
Environmental issues	exploration rate of resources, the impact of environmental change
Technology	technology advancement, technological progress, energy sector integration based on electricity
Energy transition	shift to renewables, renewable electricity technologies
Energy infrastructure security	infrastructure failures, cost of securing energy system, cost of disruption, terrorist attacks
Cyber security of the infrastructure	cyberattacks on infrastructure, IT skills, software failures
Economy	impact of energy security on economic growth and development, unemployment rate, economic competitiveness
Social issues	social impact on energy production and consumption, consumption patterns and lifestyle, social acceptance of changing development patterns, literacy, social transformation and “De-growth” transition
Military	energy as a material for military purposes, energy as “a weapon”
Policy	governance, regulations, political system, energy policy, carbon tax, carbon pricing
Geopolitics and global energy governance	the geographical location of energy sources, population settlement, industrial intensity, conflicting political interests of states

shows the recapitulation of the conceptualization of energy security in contemporary literature. It contains the most important, most frequently raised aspects of the conceptualization of energy security. The greatest challenge of the scientific community, as it was in the past, remains the integration within a coherent, widely accepted concept of the threads and dimensions of energy security proposed by individual authors.

5. Discussion

The problem of energy security has become a subject of interest with the acceleration of economic development, particularly with the spread of industrial production. The intensification of interest in energy security has been observed for almost a century, but the history of studies on energy security as a separate area of scientific research has been taking shape only in recent decades.

Over the relatively short history of energy security studies, we can see their systematic evolution. Over time, the approach to analyzing and evaluating key aspects of energy security has gradually become more sophisticated. Nevertheless, these studies still largely refer to such disciplines as security theories, public policy, political science, and international relations [113]. The basic problems raised in this type of study include the identification of mechanisms of control of resources and energy streams and the identification of entities participating in these processes.

Research referring to the traditional perception of energy security is based on the achievements of the “geopolitical school”. The geopolitical school focuses on the issues of controlling energy resources, power balances, and resources assigned to various alliances [156]. Debates on energy technologies, coal, oil and natural gas are common here [116]. Within the geopolitical school, there is a clear shift of emphasis from the initial interest in securing the supply of military fuels and ensuring the supply of oil to the focus on the regimes of global governance [157] and the role of institutions in this process [158]. These works are shaped by modern social science theories and global governance theories and reflect contemporary trends in the global economy.

Most of the debates on energy security in the 20th century and in the early years of the 21st century referred to political theories and strategic security theories. Even the gradual expansion of the perspective of energy security with economic theories and engineering knowledge has led conceptualization of energy security problems only to a limited extent. In order to broaden the view of energy security with aspects beyond geopolitical threats, it was necessary to refer to other areas of knowledge.

A significant number of publications, instead of classification, propose an integrated form of conceptualization of energy security through quantification. This involves focusing on the development of relevant indicators and indices that signal the emergence of threats to energy security. Challenges of energy security are diverse. Therefore, the assessment of the protection of the energy system against threats implies the need to take into account the corresponding security dimensions at the stage of quantification. The quantification process has many advantages—first of all, it forces precise articulation of the methodology of the construction of meters. In addition, this process forces systematic consideration of threats and evaluation of the factors of the resilience of energy systems. Properly selected indicators can prove helpful in shaping an integrated policy in relation to energy security issues. However, quantification cannot be equated with explanation and conceptualization.

The fast pace of transformation of energy systems and their increasing complexity have undermined the legitimacy of relying only on a traditional, selective approach to energy policy and energy security. For many scholars, it has become obvious that individual problems of energy security cannot be analyzed effectively or solved in isolation. Researchers of energy systems have experienced the need to integrate knowledge from various fields in order to effectively conceptualize seemingly disconnected aspects of energy security. The concept of a next generation energy system is evolving toward Energy Internet (EI), which is a combination of energy systems and the Internet [159].

In recent decades, a new way of perceiving energy security issues has emerged. It derives its roots from the observation of nature and from the technical sciences. It uses the principles of systems analysis and is based on attempts to computer-model the functioning of complex systems. The two most important ideas that the systemic approach to the concept of energy security has introduced are:

• The risks associated with operation and security holes in complex energy systems.
• The problem of scarcity of natural resources.

The analysis of risks associated with the operation of complex energy systems has a relatively long history [160,161]. However, the increasing complexity of energy systems is accompanied by an increased sensitivity of industrialized societies to disruptions in energy supplies (regardless of the reason). These studies have shifted the focus of energy security debates from geopolitics to technical issues associated with the vulnerability of energy systems, which requires a different kind of expertise. This has prompted numerous researchers of energy systems to approach them from an engineering perspective. A set of critical infrastructure vulnerability studies addressed the problems of early warning and load distribution systems or technical standards of backup generation capacities.

The issue of resource scarcity implies that an expansive economy cannot be sustained over the long term due to natural resource limits. With regard to the problem of energy security, the “peak oil” theory reflects this issue most accurately. This theory translates into concerns regarding the possibilities of securing energy supplies over a few decades due to the depletion of fossil sources [162]. It should be noted that not all scholars are inclined toward this concept. Another widely discussed aspect of resources being limited is the idea of “global limits”. It points to other limitations on the use of energy resources, mainly climate change.

Directions in the discussion on the shape of energy systems and energy security remain strongly influenced by the nature of climate policies [55]. Emphasizing environmental priorities in shaping the energy mix radically changes the point of view on the concept of energy security [143]. Discussions on the shape of the concept of energy security are drifting toward the search for solutions that support the idea of decarbonization most effectively. Over time, assessments of the effectiveness of climate policies in terms of emission and cost reduction have become an important topic of such consideration. Both empirical reasons and the theoretical base point to the superiority of market instruments. Hence, the prevailing opinions are that a sufficiently high price of CO₂ emission allowances can radically reduce the emissions of the energy sector. Carbon pricing is regarded as a powerful tool for reducing CO₂ emissions and achieving net-zero targets [163]. An appropriate valuation of CO₂ emissions would further reduce the costs of an effective climate policy. Alternatively, in some countries, policies consisting of direct subsidies for renewable energy are preferred. On the other hand, direct support programs for RES initiatives increase the energy supply. Key factors of the RES market stimulation include: reducing the share of traditional energy sources, facilitating access to RES financing, and providing public-private support for RES projects [164].

There are more and more opinions in the literature supporting the thesis of increasing energy security through technological development, enabling higher energy efficiency [59], which also contributes to the well-being of the environment [140,165]. Energy efficiency can be increased by improving the energy equipment and processes or changing consumers’ behavior [166], allowing surplus energy to be generated for other applications. Increasing energy efficiency also has an environmental dimension [167]. The energy efficiency of fossil-fuel power plants is low. The greatest increase in energy efficiency can be achieved through the integration of the electricity-based energy sector, for example, based on renewable energy sources [168].

Literature shows a clear trend of the growing number of publications on climate change and the need for a rapid transition to clean energy under the slogan of the Green New Deal. Abandoning dirty fossil fuels and moving to clean energy would pave the way for unlimited growth of the economy. However, the prospects of unlimited expansion based on “clean energy” are questioned even by supporters of the Green New Deal. The concept of unlimited development based on clean energy has been called the “utopia of green growth” in some circles. This is connected with the costs and consequences of the transition to clean energy. The transformation of the global economy into renewable energy sources would require an unimaginable increase in the extraction of rare-earth minerals. Assuming the development of renewable energy, the demand for elements necessary in solar technology will increase in relation to the current level of extraction at the following level: silver 38–by 105%, indium 300–by 920%, lithium by 2700% [169]. Such a shocking increase in the demand for lithium would result from the need to build batteries, at the grid level, for energy storage. This would entail huge social and environmental costs. The belief that inexpensive renewable energy can cover all energy demands is a sign of faith in the power of technology. Estimates indicate that a 100% renewable energy system would incur unacceptable costs [170]. There are views saying that in developed economies, due to their negative consequences, a high level of consumption creates ethical issues [171]. Solutions to the issue of energy balance can be found on the supply or demand side. Hence, some authors question the possibility of maintaining the current rate of increase in energy consumption, arguing that the only way to achieve clean energy is to reduce energy consumption. The supporters of the “De-growth” concept are in favor of such a solution. It would involve a drastic reduction in per capita consumption in the rich world and a cultural shift toward frugal communities based on collaboration and intangible values [172]. There are calls in the literature for changing consumption patterns as well as production methods [173]. Ahmed points out that the impulse for this type of transformation may provide deterioration of the situation on a global scale [174].

The current debate, not only on energy security but on energy policy as a whole, remains influenced by the increasingly intense calls for decarbonization of the means of obtaining energy. While several years ago, for example, in EU programming documents, the energy transition was conditioned by securing the well-being of individual and business consumers, the “well-being” of the climate (understood as halting climate change) is currently a priority [175]. In energy policy, this means a reversal of priorities [176]. The latest UN report on climate change indicates that previous findings on the impact of CO₂ on climate change have been overestimated [177]. However, the conceptualization of energy security among the world’s most important economies takes different forms [178]. Ang [11] points to energy security as a field that additionally meshes with the environmental dimension and economic competitiveness.

For over a decade, Europe has been consistently struggling to integrate challenges such as the security of energy supply, social and economic objectives, as well as environmental objectives into the concept of energy security [179]. Energy policy has a critical impact on many sectors of the economy. The industry is a crucial part of the EU economy—manufacturing accounts for about 80% of EU exports and ¼ of its employment. The way in which industrial policy is conducted in the EU as a whole (of which energy policy is only an essential part) is criticized by prominent managers of transnational companies. For instance, Luca de Meo, the European Automobile Manufacturers’ Association (ACEA) President and CEO of Renault Group suggests that overregulation (including the introduction of the Euro 7 pollution rules) will lead to automotive corporations moving to “more affordable” markets (mainly the USA and China) that offer a stimulus policy. With the current regulations, Europe has no chance to compete with other regions of the world [180]. Without questioning the idea of zero-emission, Akio Toyoda, Toyota president, criticized the concept of switching to electric cars only [181]. According to this manager, it is too soon to limit oneself to battery electric cars only. The ERT report [182] indicates that the energy-intensive industry in the EU is facing an existential crisis. Unless decisive and swift action is taken to reduce energy costs for energy-intensive businesses, the damage will be irreparable and will result in a significant loss of jobs in Europe.

The threat of loss of competitiveness by the EU economy results in announcements of a carbon border tax (CBAM) [183]. Without this tax, European producers will be forced to compete with companies from other regions of the world on the basis of the existing rules, which will prevent the acceleration of the energy transition. On the other hand, CBAM is a departure from the current principles of liberal trade. In the short term, this tax will translate into higher product prices in energy-intensive industries. China, with which daily trade (imports and exports from the EU) amounts to about EUR 1.9 billion, will be the most affected by the announced tax. China’s announcements of retaliation, and the threat of cutting off important raw materials, including the ones allowing for the production of electric cars in Europe, pose a serious threat to European industry, which is heavily dependent on Chinese components.

In order to improve competitiveness, EU policies should include financial and legislative measures to improve the environment for business. As energy is a key cost factor for many industrial sectors, European competitiveness is determined by a balanced energy and climate policy [184]. Europe’s share of global industry gross value added declined from about 25% in 2000 to 16.3% in 2020. Martin Brudermüller (CEO and Chairman of the Board of Executive Directors of BASF SE) points out that global economic power has shifted East, Europe’s position in the world is in decline, and Europe faces fierce global competition. In these circumstances, Europe needs to strengthen its competitiveness, and in this respect, many omissions should be noted [185]. The issue of the degradation of European competitiveness forces us to start a discussion about industrial competitiveness and the need to act quickly due to the current challenges and limitations of the regulatory approach of the Green Deal. The EU Commission aims for climate-neutral competitiveness [167] and points to the need for transformation in all sectors of the economy. In the Commission’s view, reducing emissions while maintaining industrial competitiveness (without assessing the feasibility of such measures) would make it possible to exploit the huge potential of the global market for low-carbon technologies and services.

Europe is leading the green transition, and European companies are global leaders in creating clean value. In Europe, the energy transition aimed at increasing the share of renewable energy sources in the energy mix is mainly driven by political choice. Implementation of an economic policy aimed at changing the direction of market forces is associated with inefficiencies in the allocation of resources. From a longer perspective, such inefficiencies can lead to lost development opportunities and a reduction in prosperity across the entire society. Should the rest of the global economy not share Europe’s opinion on the rationality of energy policy choices, the European economy as a whole will be excluded from mainstream development trends as a non-competitive entity. A failure in international economic competition due to a lack of competitive capacity would mean a surrender to the domination of stronger partners and result in a loss of control over one’s own future. Therefore, the ability to compete is a basic condition for maintaining one’s identity [186].

The global market has become a battlefield on which some gain more than others, and this competitive approach based on national interest is characterized as “geo-economics”. It is referred to as the application of economic instruments to promote national interests and achieve beneficial geopolitical results [187]. The logic of the competition processes, the “winner takes it all”, results in huge resource flows with little difference in efficiency [188]. On both a macro and micro scale, even small differences in efficiency result in significant differences in competitiveness. This depends on the openness of economic systems and the free movement of resources. For the last few decades, liberal trends have dominated the global economy. Experience has shown that liberalization trends have been supported by competitive countries and entities, strengthening their positions and gaining the freedom of movement of resources as a result. By contrast, the trends of closing economies were supported by international market participants losing their competitive positions and deteriorating their positions in the international division of labor [189,190].

At the moment, the EU is built on openness, both internally and externally. It is the biggest exporter and importer of goods and services worldwide. The loss of international competitive position as a result of inefficient economic choices may prompt countries and groups of countries affected to close their economies within local groupings. These processes should take into account the acceleration of the change dynamics resulting from the increasing intensity of technological changes. In the case of Europe, it will be an additional burden to bear the costs of current geopolitical turmoil on a scale that is disproportionate to the rest of the global economy.

It appears that research on energy systems, energy policy, and energy security concepts formulated adequately to the implemented energy policies has, in a sense, come full circle. Historically, energy security concepts have been firmly rooted in geopolitical theory. After years of moving away from geopolitical issues, in many studies, this notion is addressed in the form of recommendations for controlling energy issues in lieu of a national platform at the level of international groups and, in the long run, at the global level.

In recent years, literature has been moving rapidly away from technological aspects and traditional perception of energy security (“supply concept”) to treating energy as a trigger for profound transformations of social systems by changing consumption patterns, reducing energy consumption, forcing changes in economic systems by imposing energy efficiency and environmental standards.

6. The Research Limitations and Future Research

6.1. The Research Limitations

Since there is no standard search term for the concept of “energy security”, we certainly have not been able to identify all the approaches presented in the literature using our search methods. Therefore, our findings may be biased, representing those concepts that were directly available in the databases we searched or cited in other sources we found.

6.2. Future Research

The concept of energy security is rapidly evolving. Due to the increasing complexity of energy systems and the complexity of the relations between energy systems and the environment, contemporary concepts of energy security are moving toward a holistic approach to the issues.

Energy security is an abstract phenomenon of a multidimensional nature. The research gap is not only the lack of a comprehensive definition but also the insufficient recognition of the nature of the links between energy security and its dimensions. Current and still unresolved methodological challenges in the conceptualization of energy security include:

• The need to integrate energy security aspects into a coherent concept.
• Taking into account energy security challenges in the evolution of energy systems.
• Operationalization of energy security for quantification purposes.

Additionally, the conducted review of the works dealing with the issues of energy security allows us to indicate the following issues of particular interest in the future:

• Technological Challenges

• Current trends and innovation directions for the areas of smart homes and grids. Smart homes and smart grids will benefit from the renewable energy sources transformation, and they will set the main directions of innovation in this area.
• Microgrids as decentralized groups of electricity sources. Microgrids can function autonomously as technical or economic conditions dictate. In this way, microgrids have the potential to improve the security of supply.
• Smart home technology as a tool of managing the buildings’ energy efficiency. That technology enables to coordinate elements belonging to the home atmosphere, which could be remote controlled: activated, deactivated, and regulated.
• Smart grids and advanced metering infrastructure—enabling two-way communications, providing in real-time and on-demand substantial information that include: cumulative electric energy usage, power peak demand, electric energy time-of-use, load profile.
• Integration requirements and the question of controlling the compatibility of renewable power plants with the power grid.
• The Internet of Things (IoT) in the energy sector—optimization of energy use and integration of renewable energy, privacy and security challenges of deploying IoT in the energy sector.
• Green hydrogen—technologies of producing and supplying hydrogen from clean energy sources responding to the needs of the decarbonization and electrification of industry or heavy transport.
• The trend towards decentralization of energy systems sharpens the security issue, in particular for smart grid and smart home systems.
• Enhancing power grid stability.
• New energy sources (i.e., hydrogen), new ways of energy conversion, and new energy storage options.

• Renewable Energy

• The risk of competing for materials critical to renewable energy technologies.
• Electric cars as stabilizers of the energy system.

• Geopolitics and global energy governance

• The global energy architecture governance.
• Development of a theory of energy geopolitics that could be used to predict the geopolitical implications of renewable energies.

• Energy policy

• Effectiveness of different energy policies (such as RE direct supply-side subsidization, carbon tax).

• Environmental sustainability

• A global carbon tax and the decarbonization process.
• Challenges related to economic, social and sustainable development issues affecting the security of energy supplies.
• Energy intensity of GDP.

• The social and cultural transformation of society

• “De-growth” transition.
• Transforming consumption patterns as a way to increase energy efficiency.

7. Conclusions

Energy security is an issue with wide implications that affects policies and regulations. Understanding the contemporary concept of energy security and its implications requires a holistic definition. Unfortunately, contemporary literature does not offer a precise definition of energy security that would be universally accepted. Energy security is a concept, not a form of implemented policy or strategy. Hence, it is so important to conceptualize this phenomenon.

The presented narrative review indicates that:

• The main sources of differences in perception and then conceptualization of energy security include the methods of analysis used, the type of hazard identified, and the perspective from which the concept is formulated—particularly a reference to the type of energy policy implemented (e.g., the Green New Deal).
• The conceptualization of energy security is carried out in literature within three trends:
  • traditional approaches—referring to the 4As framework. The number of such publications is steadily decreasing.
  • index approaches—attempts to quantify selected aspects of energy security (such works usually contain theoretical considerations regarding the bases of the built indicators). These types of studies are constantly being published.
  • “contemporary” approaches—publications participating in the discussion on energy security in the last dozen or so years and treating the issues broadly. These concepts refer to system analysis and take into consideration new trends in the development of energy systems. The number of such publications has been growing strongly in recent years. New periodicals are also being created as a place to exchange views on the directions of energy system transformation.
• Despite the growing number of publications, energy security should still be seen as an emerging field of knowledge. In its relatively short history, this discipline has experienced a radical evolution of concepts. Recent years have pointed to the concentration of scholars’ interests on the problems of physical availability of energy, the economic competitiveness of energy and the fastest-evolving trend—the environmental impact of energy. Scholars are trying to combine all these trends into one concept of energy security. The problem of energy security quantification remains a constant subject of focus, which leads to the development of relevant indicators and indices.
• The considerations presented above show that the definitions of energy security operating in the literature do not reflect the actual framework of this security under conditions of dynamic technological and technical progress, understanding of environmental constraints, political and geopolitical conditions, and social and civilizational transformations. Thus, we believe that the concept of energy security should be reduced to the study of quantified and unquantified relations between such areas as technological progress (not only in the field of energy), renewable energy, the environment, social and civilizational development, and political and geopolitical conditions will be a significant challenge, both cognitive but also utilitarian for transnational economies.